release: cut the v10.0.2 release

After 6 months of continuous contributions, Sonu Kapoor did finally make
it into the collaborator list.

PR Close #37777

.bazelversion

@@ -1,3 +1,3 @@
-2.1.1
+3.2.0
 # [NB: this comment has to be after the first line, see https://github.com/bazelbuild/bazelisk/issues/117]
 # When updating the Bazel version you also need to update the RBE toolchains version in package.bzl

.circleci/bazel.linux.rc

@@ -19,4 +19,12 @@ build --local_ram_resources=14336
 
 # All build executed remotely should be done using our RBE configuration.
 build:remote --google_default_credentials
+
+# Upload to GCP's Build Status viewer to allow for us to have better viewing of execution/build
+# logs. This is only done on CI as the BES (GCP's Build Status viewer) API requires credentials
+# from service accounts, rather than end user accounts.
+build:remote --bes_backend=buildeventservice.googleapis.com
+build:remote --bes_timeout=30s
+build:remote --bes_results_url="https://source.cloud.google.com/results/invocations/"
+
 build --config=remote

.circleci/config.yml

@@ -67,9 +67,6 @@ var_10: &only_on_master
 # **NOTE 1**: Pin to exact images using an ID (SHA). See https://circleci.com/docs/2.0/circleci-images/#using-a-docker-image-id-to-pin-an-image-to-a-fixed-version.
 #             (Using the tag in not necessary when pinning by ID, but include it anyway for documentation purposes.)
 # **NOTE 2**: If you change the version of the docker images, also change the `cache_key` suffix.
-# **NOTE 3**: If you change the version of the `*-browsers` docker image, make sure the
-#             `--versions.chrome` arg in `integration/bazel-schematics/test.sh` specifies a
-#             ChromeDriver version that is compatible with the Chrome version in the image.
 executors:
   default-executor:
     parameters:
@@ -120,7 +117,7 @@ commands:
             sudo apt-get update
             # Install GTK+ graphical user interface (libgtk-3-0), advanced linux sound architecture (libasound2)
             # and network security service libraries (libnss3) & X11 Screen Saver extension library (libssx1)
-            # which are dependendies of chrome & needed for karma & protractor headless chrome tests.
+            # which are dependencies of chrome & needed for karma & protractor headless chrome tests.
             # This is a very small install which takes around 7s in comparing to using the full
             # circleci/node:x.x.x-browsers image.
             sudo apt-get -y install libgtk-3-0 libasound2 libnss3 libxss1
@@ -163,7 +160,7 @@ commands:
     description: Sets up a domain that resolves to the local host.
     steps:
       - run:
-          name: Preparing environment for running tests on Saucelabs.
+          name: Preparing environment for running tests on Sauce Labs.
           command: |
             # For SauceLabs jobs, we set up a domain which resolves to the machine which launched
             # the tunnel. We do this because devices are sometimes not able to properly resolve
@@ -175,13 +172,13 @@ commands:
             setSecretVar SAUCE_ACCESS_KEY $(echo $SAUCE_ACCESS_KEY | rev)
       - run:
           # Sets up a local domain in the machine's host file that resolves to the local
-          # host. This domain is helpful in Saucelabs tests where devices are not able to
+          # host. This domain is helpful in Sauce Labs tests where devices are not able to
           # properly resolve `localhost` or `127.0.0.1` through the sauce-connect tunnel.
           name: Setting up alias domain for local host.
           command: echo "127.0.0.1 $SAUCE_LOCALHOST_ALIAS_DOMAIN" | sudo tee -a /etc/hosts
 
   # Normally this would be an individual job instead of a command.
-  # But startup and setup time for each invidual windows job are high enough to discourage
+  # But startup and setup time for each individual windows job are high enough to discourage
   # many small jobs, so instead we use a command for setup unless the gain becomes significant.
   setup_win:
     description: Setup windows node environment
@@ -599,8 +596,8 @@ jobs:
       - run:
           name: Decrypt github credentials
           # We need ensure that the same default digest is used for encoding and decoding with
-          # openssl. Openssl versions might have different default digests which can cause
-          # decryption failures based on the installed openssl version. https://stackoverflow.com/a/39641378/4317734
+          # OpenSSL. OpenSSL versions might have different default digests which can cause
+          # decryption failures based on the installed OpenSSL version. https://stackoverflow.com/a/39641378/4317734
           command: 'openssl aes-256-cbc -d -in .circleci/github_token -md md5 -k "${KEY}" -out ~/.git_credentials'
       - run: ./scripts/ci/publish-build-artifacts.sh
 

.circleci/trigger-webhook.js

@@ -60,14 +60,15 @@ if (require.resolve === module) {
 
 // Helpers
 function _main(args) {
-  triggerWebhook(...args).
-    then(({statusCode, responseText}) => (200 <= statusCode && statusCode < 400) ?
-      console.log(`Status: ${statusCode}\n${responseText}`) :
-      Promise.reject(new Error(`Request failed (status: ${statusCode}): ${responseText}`))).
-    catch(err => {
-      console.error(err);
-      process.exit(1);
-    });
+  triggerWebhook(...args)
+      .then(
+          ({statusCode, responseText}) => (200 <= statusCode && statusCode < 400) ?
+              console.log(`Status: ${statusCode}\n${responseText}`) :
+              Promise.reject(new Error(`Request failed (status: ${statusCode}): ${responseText}`)))
+      .catch(err => {
+        console.error(err);
+        process.exit(1);
+      });
 }
 
 function postJson(url, data) {
@@ -77,15 +78,12 @@ function postJson(url, data) {
       const statusCode = res.statusCode || -1;
       let responseText = '';
 
-      res.
-        on('error', reject).
-        on('data', d => responseText += d).
-        on('end', () => resolve({statusCode, responseText}));
+      res.on('error', reject)
+          .on('data', d => responseText += d)
+          .on('end', () => resolve({statusCode, responseText}));
     };
 
-    request(url, opts, onResponse).
-      on('error', reject).
-      end(JSON.stringify(data));
+    request(url, opts, onResponse).on('error', reject).end(JSON.stringify(data));
   });
 }
 

.github/ISSUE_TEMPLATE/1-bug-report.md

@@ -32,13 +32,13 @@ Existing issues often contain information about workarounds, resolution, or prog
 
 ## 🔬 Minimal Reproduction
 <!--
-Please create and share minimal reproduction of the issue starting with this template: https://stackblitz.com/fork/angular-issue-repro2
+Please create and share minimal reproduction of the issue starting with this template: https://stackblitz.com/fork/angular-ivy
 -->
 <!-- ✍️--> https://stackblitz.com/...
 
 <!--
 If StackBlitz is not suitable for reproduction of your issue, please create a minimal GitHub repository with the reproduction of the issue.
-A good way to make a minimal reproduction is to create a new app via `ng new repro-app` and add the minimum possible code to show the problem. 
+A good way to make a minimal reproduction is to create a new app via `ng new repro-app` and add the minimum possible code to show the problem.
 Share the link to the repo below along with step-by-step instructions to reproduce the problem, as well as expected and actual behavior.
 
 Issues that don't have enough info and can't be reproduced will be closed.

.ng-dev/config.ts

@@ -1,11 +1,10 @@
-import {exec} from 'shelljs';
-
-import {MergeConfig} from './dev-infra/pr/merge/config';
+import {MergeConfig} from '../dev-infra/pr/merge/config';
 
 // The configuration for `ng-dev commit-message` commands.
 const commitMessage = {
   'maxLength': 120,
   'minBodyLength': 100,
+  'minBodyLengthExcludes': ['docs'],
   'types': [
     'build',
     'ci',
@@ -34,6 +33,7 @@ const commitMessage = {
     'http',
     'language-service',
     'localize',
+    'migrations',
     'ngcc',
     'packaging',
     'platform-browser',
@@ -53,24 +53,16 @@ const commitMessage = {
 const format = {
   'clang-format': {
     'matchers': [
-      'dev-infra/**/*.{js,ts}',
-      'packages/**/*.{js,ts}',
-      '!packages/zone.js',
-      '!packages/common/locales/**/*.{js,ts}',
-      '!packages/common/src/i18n/available_locales.ts',
-      '!packages/common/src/i18n/currencies.ts',
-      '!packages/common/src/i18n/locale_en.ts',
-      'modules/benchmarks/**/*.{js,ts}',
-      'modules/playground/**/*.{js,ts}',
-      'tools/**/*.{js,ts}',
-      '!tools/gulp-tasks/cldr/extract.js',
-      '!tools/public_api_guard/**/*.d.ts',
-      '!tools/ts-api-guardian/test/fixtures/**',
-      '*.{js,ts}',
-      '!**/node_modules/**',
-      '!**/dist/**',
-      '!**/built/**',
-      '!shims_for_IE.js',
+      '**/*.{js,ts}',
+      // TODO: burn down format failures and remove aio and integration exceptions.
+      '!aio/**',
+      '!integration/**',
+      // Both third_party and .yarn are directories containing copied code which should
+      // not be modified.
+      '!third_party/**',
+      '!.yarn/**',
+      // Do not format d.ts files as they are generated
+      '!**/*.d.ts',
     ]
   },
   'buildifier': true
@@ -82,33 +74,11 @@ const github = {
   name: 'angular',
 };
 
-/**
- * Gets the name of the current patch branch. The patch branch is determined by
- * looking for upstream branches that follow the format of `{major}.{minor}.x`.
- */
-const getPatchBranchName = (): string => {
-  const branches =
-      exec(
-          `git ls-remote --heads https://github.com/${github.owner}/${github.name}.git`,
-          {silent: true})
-          .trim()
-          .split('\n');
-
-  for (let i = branches.length - 1; i >= 0; i--) {
-    const branchName = branches[i];
-    const matches = branchName.match(/refs\/heads\/([0-9]+\.[0-9]+\.x)/);
-    if (matches !== null) {
-      return matches[1];
-    }
-  }
-
-  throw Error('Could not determine patch branch name.');
-};
-
 // Configuration for the `ng-dev pr merge` command. The command can be used
 // for merging upstream pull requests into branches based on a PR target label.
 const merge = () => {
-  const patchBranch = getPatchBranchName();
+  // TODO: resume dynamically determining patch branch
+  const patch = '10.0.x';
   const config: MergeConfig = {
     githubApiMerge: false,
     claSignedLabel: 'cla: yes',
@@ -121,18 +91,19 @@ const merge = () => {
       },
       {
         pattern: 'PR target: patch-only',
-        branches: [patchBranch],
+        branches: [patch],
       },
       {
         pattern: 'PR target: master & patch',
-        branches: ['master', patchBranch],
+        branches: ['master', patch],
       },
     ],
     requiredBaseCommits: {
       // PRs that target either `master` or the patch branch, need to be rebased
       // on top of the latest commit message validation fix.
-      'master': '4341743b4a6d7e23c6f944aa9e34166b701369a1',
-      [patchBranch]: '2a53f471592f424538802907aca1f60f1177a86d'
+      // These SHAs are the commits that update the required license text in the header.
+      'master': '5aeb9a4124922d8ac08eb73b8f322905a32b0b3a',
+      [patch]: '27b95ba64a5d99757f4042073fd1860e20e3ed24'
     },
   };
   return config;

.pullapprove.yml

@@ -34,41 +34,8 @@
 ####################################################################################
 #  GitHub usernames
 ####################################################################################
-#  aikidave - Dave Shevitz
-#  alan-agius4 - Alan Agius
-#  alxhub - Alex Rickabaugh
-#  AndrewKushnir - Andrew Kushnir
-#  andrewseguin - Andrew Seguin
-#  atscott - Andrew Scott
-#  ayazhafiz - Ayaz Hafiz
-#  clydin - Charles Lyding
-#  crisbeto - Kristiyan Kostadinov
-#  dennispbrown - Denny Brown
-#  devversion - Paul Gschwendtner
-#  dgp1130 - Doug Parker
-#  filipesilva - Filipe Silva
-#  gkalpak - Georgios Kalpakas
-#  gregmagolan - Greg Magolan
-#  IgorMinar - Igor Minar
-#  jbogarthyde - Judy Bogart
-#  jelbourn - Jeremy Elbourn
-#  JiaLiPassion - Jia Li
-#  JoostK - Joost Koehoorn
-#  josephperrott - Joey Perrott
-#  juleskremer - Jules Kremer
-#  kapunahelewong - Kapunahele Wong
-#  kara - Kara Erickson
-#  kyliau - Keen Yee Liau
-#  manughub - Manu Murthy
-#  matsko - Matias Niemela
-#  mgechev - Minko Gechev
-#  mhevery - Miško Hevery
-#  michaelprentice - Michael Prentice
-#  mmalerba - Miles Malerba
-#  petebacondarwin - Pete Bacon Darwin
-#  pkozlowski-opensource - Pawel Kozlowski
-#  robwormald - Rob Wormald
-#  StephenFluin - Stephen Fluin
+# See reviewer list under `required-minimum-review` group.  Team member names and
+# usernames are managed there.
 
 
 ####################################################################################
@@ -80,8 +47,8 @@
 #  Used for approving minor changes, large-scale refactorings, and in emergency situations.
 #
 # IgorMinar
+# jelbourn
 # josephperrott
-# kara
 # mhevery
 #
 # =========================================================
@@ -100,8 +67,16 @@ version: 3
 # Meta field that goes unused by PullApprove to allow for defining aliases to be
 # used throughout the config.
 meta:
-  1: &can-be-global-approved "\"global-approvers\" not in groups.approved"
-  2: &can-be-global-docs-approved "\"global-docs-approvers\" not in groups.approved"
+  can-be-global-approved: &can-be-global-approved "\"global-approvers\" not in groups.approved"
+  can-be-global-docs-approved: &can-be-global-docs-approved "\"global-docs-approvers\" not in groups.approved"
+  defaults: &defaults
+    reviews:
+      # Authors provide their approval implicitly, this approval allows for a reviewer
+      # from a group not to need a review specifically for an area of the repository
+      # they own.  This is coupled with the `required-minimum-review` group which requires
+      # that all PRs are reviewed by at least one team member who is not the author of
+      # the PR.
+      author_value: 1
 
 # turn on 'draft' support
 # https://docs.pullapprove.com/config/github-api-version/
@@ -121,6 +96,55 @@ pullapprove_conditions:
 
 
 groups:
+  # =========================================================
+  # Require review on all PRs
+  #
+  # All PRs require at least one review.  This rule will not
+  # request any reviewers, however will require that at least
+  # one review is provided before the group is satisfied.
+  # =========================================================
+  required-minimum-review:
+    reviews:
+      request: 0 # Do not request any reviews from the reviewer group
+      required: 1 # Require that all PRs have approval from at least one of the users in the group
+      author_value: 0 # The author of the PR cannot provide an approval for themself
+    reviewers:
+      users:
+         - aikidave                # Dave Shevitz
+         - alan-agius4             # Alan Agius
+         - alxhub                  # Alex Rickabaugh
+         - AndrewKushnir           # Andrew Kushnir
+         - andrewseguin            # Andrew Seguin
+         - atscott                 # Andrew Scott
+         - ayazhafiz               # Ayaz Hafiz
+         - clydin                  # Charles Lyding
+         - crisbeto                # Kristiyan Kostadinov
+         - dennispbrown            # Denny Brown
+         - devversion              # Paul Gschwendtner
+         - dgp1130                 # Doug Parker
+         - filipesilva             # Filipe Silva
+         - gkalpak                 # Georgios Kalpakas
+         - gregmagolan             # Greg Magolan
+         - IgorMinar               # Igor Minar
+         - jbogarthyde             # Judy Bogart
+         - jelbourn                # Jeremy Elbourn
+         - JiaLiPassion            # Jia Li
+         - JoostK                  # Joost Koehoorn
+         - josephperrott           # Joey Perrott
+         - juleskremer             # Jules Kremer
+         - kapunahelewong          # Kapunahele Wong
+         - kara                    # Kara Erickson
+         - kyliau                  # Keen Yee Liau
+         - manughub                # Manu Murthy
+         - matsko                  # Matias Niemela
+         - mgechev                 # Minko Gechev
+         - mhevery                 # Miško Hevery
+         - michaelprentice         # Michael Prentice
+         - mmalerba                # Miles Malerba
+         - petebacondarwin         # Pete Bacon Darwin
+         - pkozlowski-opensource   # Pawel Kozlowski
+         - StephenFluin            # Stephen Fluin
+
   # =========================================================
   #  Global Approvers
   #
@@ -161,6 +185,7 @@ groups:
   #  Framework: Animations
   # =========================================================
   fw-animations:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -185,6 +210,7 @@ groups:
   #  Framework: Compiler
   # =========================================================
   fw-compiler:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -203,13 +229,13 @@ groups:
         - alxhub
         - AndrewKushnir
         - JoostK
-        - kara
 
 
   # =========================================================
   #  Framework: Compiler / ngcc
   # =========================================================
   fw-ngcc:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -226,6 +252,7 @@ groups:
   #  Framework: Migrations
   # =========================================================
   fw-migrations:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -235,13 +262,13 @@ groups:
         - alxhub
         - crisbeto
         - devversion
-        - kara
 
 
   # =========================================================
   #  Framework: Core
   # =========================================================
   fw-core:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -352,7 +379,7 @@ groups:
         - alxhub
         - AndrewKushnir
         - atscott
-        - kara
+        - ~kara  # do not request reviews from Kara, but allow her to approve PRs
         - mhevery
         - pkozlowski-opensource
 
@@ -361,6 +388,7 @@ groups:
   #  Framework: Http
   # =========================================================
   fw-http:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -382,6 +410,7 @@ groups:
   #  Framework: Elements
   # =========================================================
   fw-elements:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -402,6 +431,7 @@ groups:
   #  Framework: Forms
   # =========================================================
   fw-forms:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -434,6 +464,7 @@ groups:
   #  Framework: i18n
   # =========================================================
   fw-i18n:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -467,6 +498,7 @@ groups:
   #  Framework: Platform Server
   # =========================================================
   fw-platform-server:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -486,6 +518,7 @@ groups:
   #  Framework: Router
   # =========================================================
   fw-router:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -508,6 +541,7 @@ groups:
   #  Framework: Service Worker
   # =========================================================
   fw-service-worker:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -535,6 +569,7 @@ groups:
   #  Framework: Upgrade
   # =========================================================
   fw-upgrade:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -565,6 +600,7 @@ groups:
   #  Framework: Testing
   # =========================================================
   fw-testing:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -579,7 +615,6 @@ groups:
       users:
         - AndrewKushnir
         - IgorMinar
-        - kara
         - pkozlowski-opensource
 
 
@@ -587,6 +622,7 @@ groups:
   #  Framework: Benchmarks
   # =========================================================
   fw-benchmarks:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - >
@@ -596,7 +632,6 @@ groups:
     reviewers:
       users:
         - IgorMinar
-        - kara
         - pkozlowski-opensource
 
 
@@ -604,6 +639,7 @@ groups:
   #  Framework: Playground
   # =========================================================
   fw-playground:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - >
@@ -613,13 +649,15 @@ groups:
     reviewers:
       users:
         - IgorMinar
-        - kara
+        - jelbourn
+        - pkozlowski-opensource
 
 
   # =========================================================
   #  Framework: Security
   # =========================================================
   fw-security:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -637,18 +675,25 @@ groups:
       users:
         - IgorMinar
         - mhevery
+        - jelbourn
+        - pkozlowski-opensource
+    reviews:
+      request: -1   # request reviews from everyone
+      required: 2   # require at least 2 approvals
+      reviewed_for: required
+
 
   # =========================================================
   #  Bazel
   # =========================================================
   bazel:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
       - >
         contains_any_globs(files, [
           'packages/bazel/**',
-          'aio/content/guide/bazel.md'
           ])
     reviewers:
       users:
@@ -661,6 +706,7 @@ groups:
   #  Language Service
   # =========================================================
   language-service:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -680,6 +726,7 @@ groups:
   #  zone.js
   # =========================================================
   zone-js:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -698,6 +745,7 @@ groups:
   #  Benchpress
   # =========================================================
   benchpress:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -708,12 +756,14 @@ groups:
     reviewers:
       users:
         - alxhub
+        - josephperrott
 
 
   # =========================================================
   #  Integration Tests
   # =========================================================
   integration-tests:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - >
@@ -724,7 +774,6 @@ groups:
       users:
         - IgorMinar
         - josephperrott
-        - kara
         - mhevery
 
 
@@ -732,6 +781,7 @@ groups:
   #  Docs: Gettings Started & Tutorial
   # =========================================================
   docs-getting-started-and-tutorial:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -764,6 +814,7 @@ groups:
   #  Docs: Marketing
   # =========================================================
   docs-marketing:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -786,6 +837,7 @@ groups:
   #  Docs: Observables
   # =========================================================
   docs-observables:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -811,6 +863,7 @@ groups:
   #  Docs: Packaging, Tooling, Releasing
   # =========================================================
   docs-packaging-and-releasing:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -830,20 +883,47 @@ groups:
           'aio/content/guide/migration-localize.md',
           'aio/content/guide/migration-module-with-providers.md',
           'aio/content/guide/static-query-migration.md',
-          'aio/content/guide/updating-to-version-9.md',
+          'aio/content/guide/updating-to-version-10.md',
           'aio/content/guide/ivy-compatibility.md',
           'aio/content/guide/ivy-compatibility-examples.md'
           ])
     reviewers:
       users:
         - IgorMinar
-        - kara
+        - jelbourn
+
+
+  # =========================================================
+  #  Tooling: Compiler API shared with Angular CLI
+  #
+  #  Changing this API might break Angular CLI, so we require
+  #  the CLI team to approve changes here.
+  # =========================================================
+  tooling-cli-shared-api:
+    conditions:
+      - *can-be-global-approved
+      - *can-be-global-docs-approved
+      - >
+        contains_any_globs(files, [
+          'packages/compiler-cli/src/tooling.ts'
+        ])
+    reviewers:
+      users:
+        - alan-agius4
+        - clydin
+        - kyliau
+        - IgorMinar
+    reviews:
+      request: -1   # request reviews from everyone
+      required: 2   # require at least 2 approvals
+      reviewed_for: required
 
 
   # =========================================================
   #  Docs: CLI
   # =========================================================
   docs-cli:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -860,8 +940,12 @@ groups:
           'aio/content/images/guide/deployment/**',
           'aio/content/guide/file-structure.md',
           'aio/content/guide/ivy.md',
+          'aio/content/guide/strict-mode.md',
           'aio/content/guide/web-worker.md',
           'aio/content/guide/workspace-config.md',
+          'aio/content/guide/migration-solution-style-tsconfig.md',
+          'aio/content/guide/migration-update-module-and-target-compiler-options.md',
+          'aio/content/guide/migration-update-libraries-tslib.md',
           ])
     reviewers:
       users:
@@ -874,6 +958,7 @@ groups:
   #  Docs: CLI Libraries
   # =========================================================
   docs-libraries:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -894,6 +979,7 @@ groups:
   #  Docs: Schematics
   # =========================================================
   docs-schematics:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -916,6 +1002,7 @@ groups:
   #  Docs-infra
   # =========================================================
   docs-infra:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - *can-be-global-docs-approved
@@ -945,14 +1032,16 @@ groups:
   #  Dev-infra
   # =========================================================
   dev-infra:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - >
-        contains_any_globs(files.exclude("CHANGELOG.md"), [
+        contains_any_globs(files.exclude("CHANGELOG.md").exclude("packages/compiler-cli/**/BUILD.bazel"), [
           '*',
           '.circleci/**',
           '.devcontainer/**',
           '.github/**',
+          '.ng-dev/**',
           '.vscode/**',
           '.yarn/**',
           'dev-infra/**',
@@ -968,8 +1057,6 @@ groups:
           'docs/TOOLS.md',
           'docs/TRIAGE_AND_LABELS.md',
           'goldens/*',
-          'modules/e2e_util/e2e_util.ts',
-          'modules/e2e_util/perf_util.ts',
           'modules/*',
           'packages/*',
           'packages/examples/test-utils/**',
@@ -977,15 +1064,10 @@ groups:
           'packages/examples/*',
           'scripts/**',
           'third_party/**',
-          'tools/brotli-cli/**',
-          'tools/browsers/**',
           'tools/build/**',
           'tools/circular_dependency_test/**',
           'tools/contributing-stats/**',
-          'tools/components/**',
           'tools/gulp-tasks/**',
-          'tools/ng_rollup_bundle/**',
-          'tools/ngcontainer/**',
           'tools/npm/**',
           'tools/npm_integration_test/**',
           'tools/rxjs/**',
@@ -1015,6 +1097,7 @@ groups:
   #  Public API
   # =========================================================
   public-api:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - >
@@ -1029,14 +1112,21 @@ groups:
           ])
     reviewers:
       users:
+        - alxhub
         - IgorMinar
-        - kara
+        - jelbourn
+        - pkozlowski-opensource
+    reviews:
+      request: -1   # request reviews from everyone
+      required: 3   # require at least 3 approvals
+      reviewed_for: required
 
 
   # ================================================
   #  Size tracking
   # ================================================
   size-tracking:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - >
@@ -1045,14 +1135,21 @@ groups:
           ])
     reviewers:
       users:
+        - alxhub
         - IgorMinar
-        - kara
+        - jelbourn
+        - pkozlowski-opensource
+    reviews:
+      request: -1   # request reviews from everyone
+      required: 2   # require at least 2 approvals
+      reviewed_for: required
 
 
   # ================================================
   #  Circular dependencies
   # ================================================
   circular-dependencies:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - >
@@ -1062,8 +1159,9 @@ groups:
     reviewers:
       users:
         - IgorMinar
+        - jelbourn
         - josephperrott
-        - kara
+        - pkozlowski-opensource
 
 
 ####################################################################################
@@ -1074,6 +1172,7 @@ groups:
   #  Code Ownership
   # =========================================================
   code-ownership:
+    <<: *defaults
     conditions:
       - *can-be-global-approved
       - >
@@ -1089,12 +1188,33 @@ groups:
   #  Catch all for if no groups match the code change
   # ====================================================
   fallback:
+    <<: *defaults
+    # A group is considered to be `active` for a PR if at least one of group's
+    # conditions matches the PR.
+    #
+    # The PullApprove CI check should fail if a PR has no `active` groups, as
+    # this indicates the PR is modifying a file that has no owner.
+    #
+    # This is enforced through the pullapprove verification check done
+    # as part of the CircleCI lint job.  Failures in this lint job should be
+    # fixed as part of the PR.  This can be done by updating the
+    # `.pullapprove.yml` file cover the unmatched path.
+    # The pullapprove verification script is part of the ng-dev tool and can be
+    # run locally with the command: `yarn -s ng-dev pullapprove verify`
+    #
+    # For cases in which the verification check fails to ensure coverage, this
+    # group will be active.  The expectation is that this should be remedied
+    # before merging the PR as described above.  In an emergency situation
+    # `global-approvers` can still approve PRs that match this `fallback` rule,
+    # but that should be an exception and not an expectation.
     conditions:
       - *can-be-global-approved
-      # Groups which are found to have matching conditions are `active`
-      # according to PullApprove. If no groups are matched and considered
-      # active, we still want to have a review occur.
-      - len(groups.active) == 0
-    reviewers:
-      users:
-        - IgorMinar
+      # The following groups have no conditions and will be `active` on all PRs
+      # - `global-approvers`
+      # - `global-docs-approvers`
+      #
+      # Since this means the minimum number of active groups a PR can have is 2, this
+      # `fallback` group should be matched anytime the number of active groups is at or
+      # below this minimum.  This work as a protection to ensure that pullapprove does
+      # not incidently mark a PR as passing without meeting the review criteria.
+      - len(groups.active) <= 2

BUILD.bazel

@@ -2,7 +2,6 @@ package(default_visibility = ["//visibility:public"])
 
 exports_files([
     "LICENSE",
-    "protractor-perf.conf.js",
     "karma-js.conf.js",
     "browser-providers.conf.js",
     "scripts/ci/track-payload-size.sh",
@@ -25,7 +24,7 @@ filegroup(
         "//packages/zone.js/dist:zone-testing.js",
         "//packages/zone.js/dist:task-tracking.js",
         "//:test-events.js",
-        "//:shims_for_IE.js",
+        "//:third_party/shims_for_IE.js",
         # Including systemjs because it defines `__eval`, which produces correct stack traces.
         "@npm//:node_modules/systemjs/dist/system.src.js",
         "@npm//:node_modules/reflect-metadata/Reflect.js",

CONTRIBUTING.md

@@ -22,7 +22,7 @@ Do not open issues for general support questions as we want to keep GitHub issue
 Stack Overflow is a much better place to ask questions since:
 
 - there are thousands of people willing to help on Stack Overflow
-- questions and answers stay available for public viewing so your question / answer might help someone else
+- questions and answers stay available for public viewing so your question/answer might help someone else
 - Stack Overflow's voting system assures that the best answers are prominently visible.
 
 To save your and our time, we will systematically close all issues that are requests for general support and redirect people to Stack Overflow.
@@ -42,7 +42,9 @@ Please consider what kind of change it is:
 
 * For a **Major Feature**, first open an issue and outline your proposal so that it can be
 discussed. This will also allow us to better coordinate our efforts, prevent duplication of work,
-and help you to craft the change so that it is successfully accepted into the project.
+and help you to craft the change so that it is successfully accepted into the project. **Note**:
+Adding a new topic to the documentation, or significantly re-writing a topic, counts as a major
+feature.
 * **Small Features** can be crafted and directly [submitted as a Pull Request](#submit-pr).
 
 ## <a name="submit"></a> Submission Guidelines
@@ -55,7 +57,7 @@ We want to fix all the issues as soon as possible, but before fixing a bug we ne
 
 A minimal reproduction allows us to quickly confirm a bug (or point out a coding problem) as well as confirm that we are fixing the right problem.
 
-We will be insisting on a minimal reproduction scenario in order to save maintainers time and ultimately be able to fix more bugs. Interestingly, from our experience, users often find coding problems themselves while preparing a minimal reproduction. We understand that sometimes it might be hard to extract essential bits of code from a larger codebase but we really need to isolate the problem before we can fix it.
+We will be insisting on a minimal reproduction scenario in order to save maintainers' time and ultimately be able to fix more bugs. Interestingly, from our experience, users often find coding problems themselves while preparing a minimal reproduction. We understand that sometimes it might be hard to extract essential bits of code from a larger codebase but we really need to isolate the problem before we can fix it.
 
 Unfortunately, we are not able to investigate / fix bugs without a minimal reproduction, so if we don't hear back from you, we are going to close an issue that doesn't have enough info to be reproduced.
 
@@ -68,7 +70,7 @@ Before you submit your Pull Request (PR) consider the following guidelines:
 1. Search [GitHub](https://github.com/angular/angular/pulls) for an open or closed PR
   that relates to your submission. You don't want to duplicate effort.
 1. Be sure that an issue describes the problem you're fixing, or documents the design for the feature you'd like to add.
-  Discussing the design up front helps to ensure that we're ready to accept your work.
+  Discussing the design upfront helps to ensure that we're ready to accept your work.
 1. Please sign our [Contributor License Agreement (CLA)](#cla) before sending PRs.
   We cannot accept code without this. Make sure you sign with the primary email address of the Git identity that has been granted access to the Angular repository.
 1. Fork the angular/angular repo.
@@ -83,8 +85,7 @@ Before you submit your Pull Request (PR) consider the following guidelines:
 1. Run the full Angular test suite, as described in the [developer documentation][dev-doc],
   and ensure that all tests pass.
 1. Commit your changes using a descriptive commit message that follows our
-  [commit message conventions](#commit). Adherence to these conventions
-  is necessary because release notes are automatically generated from these messages.
+  [commit message conventions](#commit). Adherence to these conventions is necessary because release notes are automatically generated from these messages.
 
      ```shell
      git commit -a
@@ -179,13 +180,13 @@ Samples: (even more [samples](https://github.com/angular/angular/commits/master)
 docs(changelog): update changelog to beta.5
 ```
 ```
-fix(release): need to depend on latest rxjs and zone.js
+fix(release): need to depend on the latest rxjs and zone.js
 
 The version in our package.json gets copied to the one we publish, and users need the latest of these.
 ```
 
 ### Revert
-If the commit reverts a previous commit, it should begin with `revert: `, followed by the header of the reverted commit. In the body it should say: `This reverts commit <hash>.`, where the hash is the SHA of the commit being reverted.
+If the commit reverts a previous commit, it should begin with `revert: `, followed by the header of the reverted commit. In the body, it should say: `This reverts commit <hash>.`, where the hash is the SHA of the commit being reverted.
 
 ### Type
 Must be one of the following:
@@ -236,6 +237,7 @@ There are currently a few exceptions to the "use package name" rule:
 * **docs-infra**: used for docs-app (angular.io) related changes within the /aio directory of the
   repo
 * **dev-infra**: used for dev-infra related changes within the directories /scripts, /tools and /dev-infra
+* **migrations**: used for changes to the `ng update` migrations.
 * **ngcc**: used for changes to the [Angular Compatibility Compiler](./packages/compiler-cli/ngcc/README.md)
 * **ve**: used for changes specific to ViewEngine (legacy compiler/renderer).
 * none/empty string: useful for `style`, `test` and `refactor` changes that are done across all
@@ -279,7 +281,7 @@ changes to be accepted, the CLA must be signed. It's a quick process, we promise
   * https://help.github.com/articles/about-commit-email-addresses/
   * https://help.github.com/articles/blocking-command-line-pushes-that-expose-your-personal-email-address/
 
-  Note that if you have more than one Git identity, it is important to verify that you are logged in with the same ID with which you signed the CLA, before you commit changes. If not, your PR will fail the CLA check.
+  Note that if you have more than one Git identity, it is important to verify that you are logged in with the same ID with which you signed the CLA before you commit changes. If not, your PR will fail the CLA check.
 
 <hr>
 

WORKSPACE

@@ -8,8 +8,8 @@ load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 # Fetch rules_nodejs so we can install our npm dependencies
 http_archive(
     name = "build_bazel_rules_nodejs",
-    sha256 = "f9e7b9f42ae202cc2d2ce6d698ccb49a9f7f7ea572a78fd451696d03ef2ee116",
-    urls = ["https://github.com/bazelbuild/rules_nodejs/releases/download/1.6.0/rules_nodejs-1.6.0.tar.gz"],
+    sha256 = "84abf7ac4234a70924628baa9a73a5a5cbad944c4358cf9abdb4aab29c9a5b77",
+    urls = ["https://github.com/bazelbuild/rules_nodejs/releases/download/1.7.0/rules_nodejs-1.7.0.tar.gz"],
 )
 
 # Check the rules_nodejs version and download npm dependencies
@@ -17,7 +17,7 @@ http_archive(
 # assert on that.
 load("@build_bazel_rules_nodejs//:index.bzl", "check_rules_nodejs_version", "node_repositories", "yarn_install")
 
-check_rules_nodejs_version(minimum_version_string = "1.6.0")
+check_rules_nodejs_version(minimum_version_string = "1.7.0")
 
 # Setup the Node.js toolchain
 node_repositories(
@@ -64,7 +64,7 @@ load("@io_bazel_rules_webtesting//web:repositories.bzl", "web_test_repositories"
 
 web_test_repositories()
 
-load("//tools/browsers:browser_repositories.bzl", "browser_repositories")
+load("//dev-infra/browsers:browser_repositories.bzl", "browser_repositories")
 
 browser_repositories()
 
@@ -91,17 +91,18 @@ rbe_autoconfig(
     # Need to specify a base container digest in order to ensure that we can use the checked-in
     # platform configurations for the "ubuntu16_04" image. Otherwise the autoconfig rule would
     # need to pull the image and run it in order determine the toolchain configuration. See:
-    # https://github.com/bazelbuild/bazel-toolchains/blob/1.1.2/configs/ubuntu16_04_clang/versions.bzl
-    base_container_digest = "sha256:1ab40405810effefa0b2f45824d6d608634ccddbf06366760c341ef6fbead011",
+    # https://github.com/bazelbuild/bazel-toolchains/blob/3.2.0/configs/ubuntu16_04_clang/versions.bzl
+    base_container_digest = "sha256:5e750dd878df9fcf4e185c6f52b9826090f6e532b097f286913a428290622332",
     # Note that if you change the `digest`, you might also need to update the
     # `base_container_digest` to make sure marketplace.gcr.io/google/rbe-ubuntu16-04-webtest:<digest>
     # and marketplace.gcr.io/google/rbe-ubuntu16-04:<base_container_digest> have
     # the same Clang and JDK installed. Clang is needed because of the dependency on
     # @com_google_protobuf. Java is needed for the Bazel's test executor Java tool.
-    digest = "sha256:0b8fa87db4b8e5366717a7164342a029d1348d2feea7ecc4b18c780bc2507059",
+    digest = "sha256:f743114235a43355bf8324e2ba0fa6a597236fe06f7bc99aaa9ac703631c306b",
     env = clang_env(),
     registry = "marketplace.gcr.io",
     # We can't use the default "ubuntu16_04" RBE image provided by the autoconfig because we need
     # a specific Linux kernel that comes with "libx11" in order to run headless browser tests.
     repository = "google/rbe-ubuntu16-04-webtest",
+    use_checked_in_confs = "Force",
 )

aio/content/cli/index.md

@@ -109,9 +109,3 @@ Options that specify files can be given as absolute paths, or as paths relative
 The [ng generate](cli/generate) and  [ng add](cli/add) commands take as an argument the artifact or library to be generated or added to the current project.
 In addition to any general options, each artifact or library defines its own options in a *schematic*.
 Schematic options are supplied to the command in the same format as immediate command options.
-
-
-### Building with Bazel
-
-Optionally, you can configure the Angular CLI to use [Bazel](https://docs.bazel.build) as the build tool. For more information, see [Building with Bazel](guide/bazel).
-

aio/content/examples/forms/src/app/app.module.ts

@@ -3,7 +3,7 @@ import { NgModule }      from '@angular/core';
 import { BrowserModule } from '@angular/platform-browser';
 import { FormsModule }   from '@angular/forms';
 
-import { AppComponent }  from './app.component';
+import { AppComponent }      from './app.component';
 import { HeroFormComponent } from './hero-form/hero-form.component';
 
 @NgModule({

aio/content/examples/forms/src/app/hero-form/hero-form.component.html

@@ -200,13 +200,4 @@
            (ngModelChange)="model.name = $event">
     TODO: remove this: {{model.name}}
   <!-- #enddocregion ngModel-3-->
-  <hr>
-  <!-- #docregion ngModelName-2 -->
-       <input type="text" class="form-control" id="name"
-         required
-         [(ngModel)]="model.name" name="name"
-         #spy>
-       <br>TODO: remove this: {{spy.className}}
-  <!-- #enddocregion ngModelName-2 -->
-
 </div>

aio/content/examples/forms/src/app/hero-form/hero-form.component.ts

@@ -2,7 +2,7 @@
 // #docregion , v1, final
 import { Component } from '@angular/core';
 
-import { Hero }    from '../hero';
+import { Hero } from '../hero';
 
 @Component({
   selector: 'app-hero-form',

aio/content/examples/http/src/app/http-interceptors/caching-interceptor.ts

@@ -13,13 +13,13 @@ import { searchUrl } from '../package-search/package-search.service';
 
 
 /**
- * If request is cachable (e.g., package search) and
+ * If request is cacheable (e.g., package search) and
  * response is in cache return the cached response as observable.
  * If has 'x-refresh' header that is true,
  * then also re-run the package search, using response from next(),
  * returning an observable that emits the cached response first.
  *
- * If not in cache or not cachable,
+ * If not in cache or not cacheable,
  * pass request through to next()
  */
 // #docregion v1
@@ -28,8 +28,8 @@ export class CachingInterceptor implements HttpInterceptor {
   constructor(private cache: RequestCache) {}
 
   intercept(req: HttpRequest<any>, next: HttpHandler) {
-    // continue if not cachable.
-    if (!isCachable(req)) { return next.handle(req); }
+    // continue if not cacheable.
+    if (!isCacheable(req)) { return next.handle(req); }
 
     const cachedResponse = this.cache.get(req);
     // #enddocregion v1
@@ -51,11 +51,11 @@ export class CachingInterceptor implements HttpInterceptor {
 // #enddocregion v1
 
 
-/** Is this request cachable? */
-function isCachable(req: HttpRequest<any>) {
-  // Only GET requests are cachable
+/** Is this request cacheable? */
+function isCacheable(req: HttpRequest<any>) {
+  // Only GET requests are cacheable
   return req.method === 'GET' &&
-    // Only npm package search is cachable in this app
+    // Only npm package search is cacheable in this app
     -1 < req.url.indexOf(searchUrl);
 }
 

aio/content/examples/i18n/stackblitz.json

@@ -0,0 +1,10 @@
+{
+    "description": "i18n",
+    "files":[
+      "!**/*.d.ts",
+      "!**/*.js",
+      "!**/*.[0-9].*"
+    ],
+    "file": "src/app/app.component.ts", 
+    "tags": ["Angular", "i18n", "internationalization"]
+}

aio/content/examples/pipes/src/app/app.component.ts

@@ -6,5 +6,5 @@ import { Component } from '@angular/core';
   templateUrl: './app.component.html'
 })
 export class AppComponent {
-  birthday = new Date(1988, 3, 15); // April 15, 1988
+  birthday = new Date(1988, 3, 15); // April 15, 1988 -- since month parameter is zero-based
 }

aio/content/examples/pipes/src/app/hero-birthday1.component.ts

@@ -8,5 +8,5 @@ import { Component } from '@angular/core';
   // #enddocregion hero-birthday-template
 })
 export class HeroBirthdayComponent {
-  birthday = new Date(1988, 3, 15); // April 15, 1988
+  birthday = new Date(1988, 3, 15); // April 15, 1988 -- since month parameter is zero-based
 }

aio/content/examples/pipes/src/app/hero-birthday2.component.ts

@@ -12,7 +12,7 @@ import { Component } from '@angular/core';
 })
 // #docregion class
 export class HeroBirthday2Component {
-  birthday = new Date(1988, 3, 15); // April 15, 1988
+  birthday = new Date(1988, 3, 15); // April 15, 1988 -- since month parameter is zero-based
   toggle = true; // start with true == shortDate
 
   get format()   { return this.toggle ? 'shortDate' : 'fullDate'; }

aio/content/examples/toh-pt4/src/app/heroes/heroes.component.ts

@@ -33,7 +33,7 @@ export class HeroesComponent implements OnInit {
 
   onSelect(hero: Hero): void {
     this.selectedHero = hero;
-    this.messageService.add(`HeroService: Selected hero id=${hero.id}`);
+    this.messageService.add(`HeroesComponent: Selected hero id=${hero.id}`);
   }
 
   // #docregion getHeroes

aio/content/guide/angular-compiler-options.md

@@ -1,6 +1,6 @@
 # Angular compiler options
 
-When you use [AOT compilation](guide/aot-compiler), you can control how your application is compiled by specifying *template* compiler options in the `tsconfig.json` [TypeScript configuration file](guide/typescript-configuration).
+When you use [AOT compilation](guide/aot-compiler), you can control how your application is compiled by specifying *template* compiler options in the [TypeScript configuration file](guide/typescript-configuration).
 
 The template options object, `angularCompilerOptions`, is a sibling to the `compilerOptions` object that supplies standard options to the TypeScript compiler.
 
@@ -21,11 +21,11 @@ The template options object, `angularCompilerOptions`, is a sibling to the `comp
 {@a tsconfig-extends}
 ## Configuration inheritance with extends
 
-Like the TypeScript compiler, The Angular AOT compiler also supports `extends` in the `angularCompilerOptions` section of the TypeScript configuration file, `tsconfig.json`.
+Like the TypeScript compiler, The Angular AOT compiler also supports `extends` in the `angularCompilerOptions` section of the TypeScript configuration file.
 The `extends` property is at the top level, parallel to `compilerOptions` and `angularCompilerOptions`.
 
 A TypeScript configuration can inherit settings from another file using the `extends` property.
-The configuration options from the base file are loaded first, then overridden by those in the inheriting `tsconfig` file.
+The configuration options from the base file are loaded first, then overridden by those in the inheriting configuration file.
 
 For example:
 

aio/content/guide/aot-compiler.md

@@ -105,7 +105,7 @@ For help in understanding and resolving these problems, see [AOT Metadata Errors
 
 ### Configuring AOT compilation
 
-You can provide options in the `tsconfig.json` [TypeScript configuration file](guide/typescript-configuration) that control the compilation process. See [Angular compiler options](guide/angular-compiler-options) for a complete list of available options.
+You can provide options in the [TypeScript configuration file](guide/typescript-configuration) that controls the compilation process. See [Angular compiler options](guide/angular-compiler-options) for a complete list of available options.
 
 ## Phase 1: Code analysis
 
@@ -211,7 +211,7 @@ The compiler later reports the error if it needs that piece of metadata to gener
 
 <div class="alert is-helpful">
 
- If you want `ngc` to report syntax errors immediately rather than produce a `.metadata.json` file with errors, set the `strictMetadataEmit` option in the TypeScript configuration file, `tsconfig.json`.
+ If you want `ngc` to report syntax errors immediately rather than produce a `.metadata.json` file with errors, set the `strictMetadataEmit` option in the TypeScript configuration file.
 
 ```
   "angularCompilerOptions": {
@@ -548,7 +548,7 @@ It does not, however, rewrite the `.d.ts` file, so TypeScript doesn't recognize
 One of the Angular compiler's most helpful features is the ability to type-check expressions within templates, and catch any errors before they cause crashes at runtime.
 In the template type-checking phase, the Angular template compiler uses the TypeScript compiler to validate the binding expressions in templates.
 
-Enable this phase explicitly by adding the compiler option `"fullTemplateTypeCheck"` in the `"angularCompilerOptions"` of the project's `tsconfig.json`
+Enable this phase explicitly by adding the compiler option `"fullTemplateTypeCheck"` in the `"angularCompilerOptions"` of the project's TypeScript configuration file
 (see [Angular Compiler Options](guide/angular-compiler-options)).
 
 <div class="alert is-helpful">

aio/content/guide/architecture.md

@@ -11,7 +11,7 @@ The basic building blocks are *NgModules*, which provide a compilation context f
 
 * Components use *services*, which provide specific functionality not directly related to views. Service providers can be *injected* into components as *dependencies*, making your code modular, reusable, and efficient.
 
-Both components and services are simply classes, with *decorators* that mark their type and provide metadata that tells Angular how to use them.
+Modules, components and services are classes that use *decorators*. These decorators mark their type and provide metadata that tells Angular how to use them.
 
 * The metadata for a component class associates it with a *template* that defines a view. A template combines ordinary HTML with Angular *directives* and *binding markup* that allow Angular to modify the HTML before rendering it for display.
 

aio/content/guide/bazel.md

@@ -1,122 +0,0 @@
-# Building with Bazel
-
-This guide explains how to build and test Angular apps with Bazel.
-
-
-<div class="alert is-helpful">
-
-This guide assumes you are already familiar with developing and building Angular applications using the [CLI](cli).
-
-It describes features which are part of Angular Labs, and are not considered a stable, supported API.
-
-</div>
-
-## Using Bazel with the Angular CLI
-
-The `@angular/bazel` package provides a builder that allows Angular CLI to use Bazel as the build tool.
-
-To opt-in an existing application, run
-
-```sh
-ng add @angular/bazel
-```
-
-To use Bazel in a new application, first install `@angular/bazel` globally
-
-```sh
-npm install -g @angular/bazel
-```
-
-then create the new application with
-
-```sh
-ng new --collection=@angular/bazel
-```
-
-Now when you use Angular CLI build commands such as `ng build` and `ng serve`,
-Bazel is used behind the scenes.
-Outputs from Bazel appear in the `dist/bin` folder.
-
-> The command-line output includes extra logging from Bazel.
-> We plan to reduce this in the future.
-
-### Removing Bazel
-
-If you need to opt-out from using Bazel, you can restore the backup files:
-
-- `/angular.json.bak` replaces `/angular.json`
-
-## Advanced configuration
-
-<div class="alert is-helpful">
-
-Editing the Bazel configuration may prevent you opting out of Bazel.
-Custom behaviors driven by Bazel won't be available in other Builders.
-
-This section assumes you are familiar with [Bazel](https://docs.bazel.build).
-
-</div>
-
-You can manually adjust the Bazel configuration to:
-
-* customize the build steps
-* parallellize the build for scale and incrementality
-
-Create the initial Bazel configuration files by running the following command:
-
-```sh
-ng build --leaveBazelFilesOnDisk
-```
-
-Now you'll find new files in the Angular workspace:
-
-* `/WORKSPACE` tells Bazel how to download external dependencies.
-* `/BUILD.bazel` and `/src/BUILD.bazel` tell Bazel about your source code.
-
-You can find a full-featured example with custom Bazel configurations at https://github.com/bazelbuild/rules_nodejs/tree/master/examples/angular.
-
-Documentation for using Bazel for frontend projects is linked from https://docs.bazel.build/versions/master/bazel-and-javascript.html.
-
-
-
-## Running Bazel directly
-
-In some cases you'll want to bypass the Angular CLI builder, and run the Bazel CLI directly.
-The Bazel tool is managed by the `@bazel/bazelisk` package (similar to how Node.js can be managed by `nvm`).
-You can install it globally to get the `bazelisk` command in your path, or use `$(npm bin)/bazelisk` in place of bazelisk below.
-
-The common commands in Bazel are:
-
-* `bazelisk build [targets]`: Compile the default output artifacts of the given targets.
-* `bazelisk test [targets]`: For whichever `*_test` targets are found in the patterns, run the tests.
-* `bazelisk run [target]`: Compile the program represented by target, and then run it.
-
-To repeat the command any time the inputs change (watch mode), replace `bazelisk` with `ibazel` in these commands.
-
-The output locations are printed in the output.
-
-Full documentation for the Bazel CLI is at https://docs.bazel.build/versions/master/command-line-reference.html.
-
-
-## Querying the build graph
-
-Because Bazel constructs a graph out of your targets, you can find lots of useful information.
-
-Using the graphviz optional dependency, you'll have a program `dot`, which you can use with `bazel query`:
-
-```bash
-$ bazel query --output=graph ... | dot -Tpng > graph.png
-```
-
-See https://docs.bazel.build/versions/master/query-how-to.html for more details on `bazel query`.
-
-
-## Customizing `BUILD.bazel` files
-
-"Rules" are like plugins for Bazel. Many rule sets are available. This guide documents the ones maintained by the Angular team at Google.
-
-Rules are used in `BUILD.bazel` files, which are markers for the packages in your workspace. Each `BUILD.bazel` file declares a separate package to Bazel, though you can have more coarse-grained distributions so that the packages you publish (for example, to `npm`) can be made up of many Bazel packages.
-
-In the `BUILD.bazel` file, each rule must first be imported, using the `load` statement. Then the rule is called with some attributes, and the result of calling the rule is that you've declared to Bazel how it can derive some outputs given some inputs and dependencies. Then later, when you run a `bazel` command line, Bazel loads all the rules you've declared to determine an absolute ordering of what needs to be run. Note that only the rules needed to produce the requested output will actually be executed.
-
-A list of common rules for frontend development is documented in the README at https://github.com/bazelbuild/rules_nodejs/.

aio/content/guide/browser-support.md

@@ -54,16 +54,17 @@ Angular supports most recent browsers. This includes the following specific vers
     </td>
     <td>
       <div> 11, 10*, 9* ("compatibility view" mode not supported) </div>
-      <div>*deprecated in v10, see the <a href="/guide/deprecations#ie-9-10">deprecations guide</a>.</div>
+      <div>*deprecated in v10, see the {@link guide/deprecations#ie-9-10-and-mobile deprecations guide}.</div>
     </td>
   </tr>
  <tr>
    <tr>
     <td>
-      IE Mobile
+      IE Mobile*
     </td>
     <td>
       11
+      <div>*deprecated in v10, see the {@link guide/deprecations#ie-9-10-and-mobile deprecations guide}.</div>
     </td>
   </tr>
  <tr>

aio/content/guide/build.md

@@ -262,6 +262,33 @@ Each budget entry is a JSON object with the following properties:
 
  </table>
 
+{@a commonjs }
+## Configuring CommonJS dependencies
+
+<div class="alert is-important">
+
+It is recommended that you avoid depending on CommonJS modules in your Angular applications.
+Depending on CommonJS modules can prevent bundlers and minifiers from optimizing your application, which results in larger bundle sizes.
+Instead, it is recommended that you use [ECMAScript modules](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import) in your entire application.
+For more information, see [How CommonJS is making your bundles larger](https://web.dev/commonjs-larger-bundles/).
+
+</div>
+
+The Angular CLI outputs warnings if it detects that your browser application depends on CommonJS modules.
+To disable these warnings, you can add the CommonJS module name to `allowedCommonJsDependencies` option in the `build` options located in `angular.json` file.
+
+<code-example lang="json">
+"build": {
+  "builder": "@angular-devkit/build-angular:browser",
+  "options": {
+     "allowedCommonJsDependencies": [
+        "lodash"
+     ]
+     ...
+   }
+   ...
+},
+</code-example>
 
 {@a browser-compat}
 

aio/content/guide/creating-libraries.md

@@ -109,7 +109,9 @@ To learn more, see [Schematics Overview](guide/schematics) and [Schematics for
 
 ## Publishing your library
 
-Use the Angular CLI and the npm package manager to build and publish your library as an npm package. It is not recommended to publish Ivy libraries to NPM repositories. Before publishing a library to NPM, build it using the `--prod` flag which will use the older compiler and runtime known as View Engine instead of Ivy.
+Use the Angular CLI and the npm package manager to build and publish your library as an npm package. 
+
+Before publishing a library to NPM, build it using the `--prod` flag which will use the older compiler and runtime known as View Engine instead of Ivy.
 
 <code-example language="bash">
 ng build my-lib --prod
@@ -119,6 +121,14 @@ npm publish
 
 If you've never published a package in npm before, you must create a user account. Read more in [Publishing npm Packages](https://docs.npmjs.com/getting-started/publishing-npm-packages).
 
+<div class="alert is-important">
+
+For now, it is not recommended to publish Ivy libraries to NPM because Ivy generated code is not backward compatible with View Engine, so apps using View Engine will not be able to consume them. Furthermore, the internal Ivy instructions are not yet stable, which can potentially break consumers using a different Angular version from the one used to build the library.
+
+When a published library is used in an Ivy app, the Angular CLI will automatically convert it to Ivy using a tool known as the Angular compatibility compiler (`ngcc`). Thus, by publishing your libraries using the View Engine compiler ensures that they can be transparently consumed by both View Engine and Ivy apps.
+
+</div>
+
 {@a lib-assets}
 
 ## Managing assets in a library

aio/content/guide/dependency-injection-providers.md

@@ -197,11 +197,11 @@ Like  `EvenBetterLogger`, `HeroService` needs to know if the user is authorized
 That authorization can change during the course of a single application session,
 as when you log in a different user.
 
-Let's say you don't want to inject `UserService` directly into `HeroService`, because you don't want to complicate that service with security-sensitive information.
+Imagine that you don't want to inject `UserService` directly into `HeroService`, because you don't want to complicate that service with security-sensitive information.
 `HeroService` won't have direct access to the user information to decide
 who is authorized and who isn't.
 
-To resolve this, we give the `HeroService` constructor a boolean flag to control display of secret heroes.
+To resolve this, give the `HeroService` constructor a boolean flag to control display of secret heroes.
 
 <code-example path="dependency-injection/src/app/heroes/hero.service.ts" region="internals" header="src/app/heroes/hero.service.ts (excerpt)"></code-example>
 

aio/content/guide/deployment.md

@@ -469,7 +469,7 @@ The following configurations determine your requirements.
 
 * TypeScript configuration
 
-   In the TypeScript configuration file, `tsconfig.json`, the "target" option in the `compilerOptions` section determines the ECMAScript target version that the code is compiled to.
+   In the TypeScript configuration file, the "target" option in the `compilerOptions` section determines the ECMAScript target version that the code is compiled to.
    Modern browsers support ES2015 natively, while ES5 is more commonly used to support legacy browsers.
 
 <div class="alert is-helpful">

aio/content/guide/deprecations.md

@@ -35,6 +35,7 @@ v9 - v12
 
 | Area                          | API or Feature                                                                | May be removed in |
 | ----------------------------- | ---------------------------------------------------------------------------   | ----------------- |
+| `@angular/bazel`              | [`Bazel builder and schematics`](#bazelbuilder)                               | v10 |
 | `@angular/common`             | [`ReflectiveInjector`](#reflectiveinjector)                                   | <!--v8--> v11 |
 | `@angular/common`             | [`CurrencyPipe` - `DEFAULT_CURRENCY_CODE`](api/common/CurrencyPipe#currency-code-deprecation) | <!--v9--> v11 |
 | `@angular/core`               | [`CollectionChangeRecord`](#core)                                             | <!--v7--> v11 |
@@ -59,7 +60,7 @@ v9 - v12
 | `@angular/core/testing`       | [`TestBed.get`](#testing)                                                     | <!--v9--> v12 |
 | `@angular/router`             | [`ActivatedRoute` params and `queryParams` properties](#activatedroute-props) | unspecified |
 | template syntax               | [`/deep/`, `>>>`, and `::ng-deep`](#deep-component-style-selector)            | <!--v7--> unspecified |
-| browser support               | [`IE 9 and 10`](#ie-9-10)                                                     | <!--v10--> v11 |
+| browser support               | [`IE 9 and 10, IE mobile`](#ie-9-10-and-mobile)                               | <!--v10--> v11 |
 
 
 
@@ -160,7 +161,11 @@ Tip: In the [API reference section](api) of this doc site, deprecated APIs are i
 
 This section lists all of the currently-deprecated features, which includes template syntax, configuration options, and any other deprecations not listed in the [Deprecated APIs](#deprecated-apis) section above. It also includes deprecated API usage scenarios or API combinations, to augment the information above.
 
+{@a bazelbuilder}
+### Bazel builder and schematics
 
+Bazel builder and schematics were introduced in Angular Labs to let users try out Bazel without having to manage Bazel version and BUILD files.
+This feature has been deprecated. For more information, please refer to the [migration doc](https://github.com/angular/angular/blob/master/packages/bazel/src/schematics/README.md).
 
 {@a wtf}
 ### Web Tracing Framework integration
@@ -459,17 +464,17 @@ export class MyModule {
 ```
 
 
-{@a ie-9-10}
-### IE 9 and 10 support
+{@a ie-9-10-and-mobile}
+### IE 9, 10, and IE mobile support
 
-Support for IE 9 and 10 has been deprecated and will be removed in a future version.
+Support for IE 9 and 10 has been deprecated, as well as support for IE Mobile. These will be dropped in a future version.
 Supporting outdated browsers like these increases bundle size, code complexity, and test load, and also requires time and effort that could be spent on improvements to the framework.
 For example, fixing issues can be more difficult, as a straightforward fix for modern browsers could break old ones that have quirks due to not receiving updates from vendors.
 
 The final decision was made on three key points:
-* __Vendor support__: Microsoft dropped support of IE 9 and 10 on 1/12/16, meaning they no longer provide security updates or technical support.
-* __Usage statistics__: We looked at usage trends for IE 9 and 10 from various sources and all indicated that usage percentages were extremely small (fractions of 1%).
-* __Feedback from partners__: We also reached out to some of our Angular customers and none expressed concern about dropping IE 9 and 10 support.
+* __Vendor support__: Microsoft dropped support of IE 9 and 10 on 1/12/16, meaning they no longer provide security updates or technical support. Additionally, Microsoft dropped support for Windows 10 Mobile in December 2019.
+* __Usage statistics__: We looked at usage trends for IE 9 and 10 (as well as IE Mobile) from various sources and all indicated that usage percentages were extremely small (fractions of 1%).
+* __Feedback from partners__: We also reached out to some of our Angular customers and none expressed concern about dropping IE 9, 10, nor IE Mobile support.
 
 
 {@a wrapped-value}
@@ -485,6 +490,56 @@ If you rely on the behavior that the same object instance should cause change de
 - Clone the resulting value so that it has a new identity.
 - Explicitly call [`ChangeDetectorRef.detectChanges()`](api/core/ChangeDetectorRef#detectchanges) to force the update. 
 
+{@a deprecated-cli-flags}
+## Deprecated CLI APIs and Options
+
+This section contains a complete list all of the currently deprecated CLI flags.
+
+### @angular-devkit/build-angular
+
+| API/Option                      | May be removed in | Notes                                                                           |
+| ------------------------------- | ----------------- |-------------------------------------------------------------------------------- |
+| `i18nFile`                      | <!--v9--> v11     | Specified in the project locale configuration in version 9 and later.           |
+| `i18nFormat`                    | <!--v9--> v11     | Format is now automatically detected.                                           |
+| `i18nLocale`                    | <!--v9--> v11     | New [localization option](/guide/i18n#localize-config) in version 9 and later.  |
+| `lazyModules`                   | <!--v9--> v11     | Used with deprecated SystemJsNgModuleLoader.                                    |
+| `rebaseRootRelativeCssUrls`     | <!--v8--> v11     | Intended only to assist with specific migration issues.                         |
+| `scripts[].lazy`                | <!--v8--> v11     | Renamed to `scripts[].inject`.                                                  |
+| `styles[].lazy`                 | <!--v8--> v11     | Renamed to `styles[].inject`.                                                   |
+| `i18nFormat`                    | <!--v9--> v11     | Renamed to `format` to simplify the user experience.                            |
+| `i18nLocale`                    | <!--v9--> v11     | Redundant with project’s source locale.                                         |
+| `scripts[].lazy`                | <!--v8--> v11     | Renamed to `scripts[].inject`.                                                  |
+| `styles[].lazy`                 | <!--v8--> v11     | Renamed to `styles[].inject`.                                                   |
+| `i18nFile`                      | <!--v9--> v11     | Specified in the project locale configuration in version 9 and later.           |
+| `i18nFormat`                    | <!--v9--> v11     | Format is now automatically detected.                                           |
+| `i18nLocale`                    | <!--v9--> v11     | New [localization option](/guide/i18n#localize-config) in version 9 and later.  |
+| `lazyModules`                   | <!--v9--> v11     | Used with deprecated SystemJsNgModuleLoader.                                    |
+
+### @angular-devkit/core
+
+| API/Option                      | May be removed in | Notes                                                                           |
+| ------------------------------- | ----------------- |-------------------------------------------------------------------------------- |
+| `ModuleNotFoundException`       | <!--v8--> v10     | Not used within projects. Used with Tooling API only. Not Yarn PnP compatible and not used in the Angular CLI. Use Node.js [require.resolve](https://nodejs.org/api/modules.html#modules_require_resolve_request_options).|
+| `resolve`                       | <!--v8--> v10     | Not used within projects. Used with Tooling API only. Not Yarn PnP compatible and not used in the Angular CLI. Use Node.js [require.resolve](https://nodejs.org/api/modules.html#modules_require_resolve_request_options).|
+| `setResolveHook`                | <!--v8--> v10     | Not used within projects. Used with Tooling API only. Not Yarn PnP compatible and not used in the Angular CLI. Use Node.js [require.resolve](https://nodejs.org/api/modules.html#modules_require_resolve_request_options).|
+| `ResolveOptions`                | <!--v8--> v10     | Not used within projects. Used with Tooling API only. Not Yarn PnP compatible and not used in the Angular CLI. Use Node.js [require.resolve](https://nodejs.org/api/modules.html#modules_require_resolve_request_options).|
+| `terminal`                      | <!--v8--> v10     | Unused implementation of terminal codes (color).                                |
+| `isObservable`                  | <!--v8--> v10     | Not used within projects. Used with Tooling API only. Use `isObservable` function from the `rxjs` package.|
+
+### @ngtools/webpack
+
+| API/Option                      | May be removed in | Notes                                                                           |
+| ------------------------------- | ----------------- |-------------------------------------------------------------------------------- |
+| `discoverLazyRoutes`            | <!--v9--> TBD     | Used with deprecated SystemJsNgModuleLoader.                                    |
+| `additionalLazyModules`         | <!--v9--> TBD     | Used with deprecated SystemJsNgModuleLoader.                                    |
+| `additionalLazyModuleResources` | <!--v9--> TBD     | Used with deprecated SystemJsNgModuleLoader.                                    |
+
+### @schematics/angular
+
+| API/Option                      | May be removed in | Notes                                                                           |
+| ------------------------------- | ----------------- |-------------------------------------------------------------------------------- |
+| `entryComponent`                | <!--v9--> TBD     | No longer needed with Ivy.                                                      |
+
 {@a removed}
 ## Removed APIs
 

aio/content/guide/docs-style-guide.md

@@ -931,7 +931,7 @@ If you do, be sure to set the `id` attribute - not the `name` attribute! The doc
 
 </div>
 
-## Alerts and Calllouts
+## Alerts and Callouts
 
 Alerts and callouts present warnings, extra detail or references to other pages. They can also be used to provide commentary that _enriches_ the reader's understanding of the content being presented.
 

aio/content/guide/elements.md

@@ -117,9 +117,9 @@ The recently-developed [custom elements](https://developer.mozilla.org/en-US/doc
 </tr>
 </table>
 
-In browsers that support Custom Elements natively, the specification requires developers use ES2015 classes to define Custom Elements - developers can opt-in to this by setting the `target: "es2015"` property in their project's `tsconfig.json`. As Custom Element and ES2015 support may not be available in all browsers, developers can instead choose to use a polyfill to support older browsers and ES5 code.
+In browsers that support Custom Elements natively, the specification requires developers use ES2015 classes to define Custom Elements - developers can opt-in to this by setting the `target: "es2015"` property in their project's [TypeScript configuration file](/guide/typescript-configuration). As Custom Element and ES2015 support may not be available in all browsers, developers can instead choose to use a polyfill to support older browsers and ES5 code.
 
-Use the [Angular CLI](cli) to automatically set up your project with the correct polyfill: `ng add @angular/elements --name=*your_project_name*`.
+Use the [Angular CLI](cli) to automatically set up your project with the correct polyfill: `ng add @angular/elements --project=*your_project_name*`.
 - For more information about polyfills, see [polyfill documentation](https://www.webcomponents.org/polyfills).
 
 - For more information about Angular browser support, see [Browser Support](guide/browser-support).

aio/content/guide/file-structure.md

@@ -40,7 +40,8 @@ The top level of the workspace contains workspace-wide configuration files, conf
 | `package-lock.json`     | Provides version information for all packages installed into `node_modules` by the npm client. See [npm documentation](https://docs.npmjs.com/files/package-lock.json) for details. If you use the yarn client, this file will be [yarn.lock](https://yarnpkg.com/lang/en/docs/yarn-lock/) instead. |
 | `src/`                  | Source files for the root-level application project. |
 | `node_modules/`         | Provides [npm packages](guide/npm-packages) to the entire workspace. Workspace-wide `node_modules` dependencies are visible to all projects. |
-| `tsconfig.json`         | Default [TypeScript](https://www.typescriptlang.org/) configuration for projects in the workspace. |
+| `tsconfig.json`         | The `tsconfig.json` file is a ["Solution Style"](https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-9.html#support-for-solution-style-tsconfigjson-files) TypeScript configuration file. Code editors and TypeScript’s language server use this file to improve development experience. Compilers do not use this file. |
+| `tsconfig.base.json`    | The base [TypeScript](https://www.typescriptlang.org/) configuration for projects in the workspace. All other configuration files inherit from this base file. For more information, see the [Configuration inheritance with extends](https://www.typescriptlang.org/docs/handbook/tsconfig-json.html#configuration-inheritance-with-extends) section of the TypeScript documentation.|
 | `tslint.json`           | Default [TSLint](https://palantir.github.io/tslint/) configuration for projects in the workspace. |
 
 
@@ -77,6 +78,12 @@ Files at the top level of `src/` support testing and running your application. S
 | `styles.sass`          | Lists CSS files that supply styles for a project. The extension reflects the style preprocessor you have configured for the project. |
 | `test.ts`              | The main entry point for your unit tests, with some Angular-specific configuration. You don't typically need to edit this file. |
 
+<div class="alert is-helpful">
+
+If you create an application using Angular's strict mode, you will also have an additional `package.json` file in the `src/app` directory. For more information, see [Strict mode](/guide/strict-mode).
+
+</div>
+
 {@a app-src}
 
 Inside the `src/` folder, the `app/` folder contains your project's logic and data.
@@ -89,13 +96,14 @@ Angular components, templates, and styles go here.
 | `app/app.component.css`     | Defines the base CSS stylesheet for the root `AppComponent`. |
 | `app/app.component.spec.ts` | Defines a unit test for the root `AppComponent`. |
 | `app/app.module.ts`         | Defines the root module, named `AppModule`, that tells Angular how to assemble the application. Initially declares only the `AppComponent`. As you add more components to the app, they must be declared here. |
+| `app/package.json`              | This file is generated only in applications created using `--strict` mode. This file is not used by package managers. It is used to tell the tools and bundlers whether the code under this directory is free of non-local [side-effects](guide/strict-mode#side-effect). |
 
 ### Application configuration files
 
 The application-specific configuration files for the root application reside at the workspace root level.
 For a multi-project workspace, project-specific configuration files are in the project root, under `projects/project-name/`.
 
-Project-specific [TypeScript](https://www.typescriptlang.org/) configuration files inherit from the workspace-wide `tsconfig.json`, and project-specific [TSLint](https://palantir.github.io/tslint/) configuration files inherit from the workspace-wide `tslint.json`.
+Project-specific [TypeScript](https://www.typescriptlang.org/) configuration files inherit from the workspace-wide `tsconfig.base.json`, and project-specific [TSLint](https://palantir.github.io/tslint/) configuration files inherit from the workspace-wide `tslint.json`.
 
 | APPLICATION-SPECIFIC CONFIG FILES    | PURPOSE |
 | :--------------------- | :------------------------------------------|

aio/content/guide/forms-overview.md

@@ -4,22 +4,27 @@ Handling user input with forms is the cornerstone of many common applications. A
 
 Angular provides two different approaches to handling user input through forms: reactive and template-driven. Both capture user input events from the view, validate the user input, create a form model and data model to update, and provide a way to track changes.
 
-Reactive and template-driven forms process and manage form data differently. Each offers different advantages.
-
-**In general:**
-
-* **Reactive forms** are more robust: they're more scalable, reusable, and testable. If forms are a key part of your application, or you're already using reactive patterns for building your application, use reactive forms.
-* **Template-driven forms** are useful for adding a simple form to an app, such as an email list signup form. They're easy to add to an app, but they don't scale as well as reactive forms. If you have very basic form requirements and logic that can be managed solely in the template, use template-driven forms.
-
 This guide provides information to help you decide which type of form works best for your situation. It introduces the common building blocks used by both approaches. It also summarizes the key differences between the two approaches, and demonstrates those differences in the context of setup, data flow, and testing.
 
-<div class="alert is-helpful">
+## Prerequisites
 
-**Note:** For complete information about each kind of form, see [Reactive Forms](guide/reactive-forms) and [Template-driven Forms](guide/forms).
+This guide assumes that you have a basic understanding of the following.
 
-</div>
+* [TypeScript](https://www.typescriptlang.org/docs/home.html "The TypeScript language") and HTML5 programming.
 
-## Key differences
+* Angular app-design fundamentals, as described in [Angular Concepts](guide/architecture "Introduction to Angular concepts.").
+
+* The basics of [Angular template syntax](guide/architecture-components#template-syntax "Template syntax intro").
+
+## Choosing an approach
+
+Reactive forms and template-driven forms process and manage form data differently. Each approach offers different advantages.
+
+* **Reactive forms** provide direct, explicit access to the underlying forms object model. Compared to template-driven forms, they are more robust: they're more scalable, reusable, and testable. If forms are a key part of your application, or you're already using reactive patterns for building your application, use reactive forms.
+
+* **Template-driven forms** rely on directives in the template to create and manipulate the underlying object model. They are useful for adding a simple form to an app, such as an email list signup form. They're easy to add to an app, but they don't scale as well as reactive forms. If you have very basic form requirements and logic that can be managed solely in the template, template-driven forms could be a good fit.
+
+### Key differences
 
 The table below summarizes the key differences between reactive and template-driven forms.
 
@@ -30,17 +35,33 @@ The table below summarizes the key differences between reactive and template-dri
 
 ||Reactive|Template-driven|
 |--- |--- |--- |
-|Setup (form model)|More explicit, created in component class|Less explicit, created by directives|
-|Data model|Structured|Unstructured|
-|Predictability|Synchronous|Asynchronous|
-|Form validation|Functions|Directives|
-|Mutability|Immutable|Mutable|
-|Scalability|Low-level API access|Abstraction on top of APIs|
+|[Setup of form model](#setup) | Explicit, created in component class | Implicit, created by directives |
+|[Data model](#data-flow-in-forms) | Structured and immutable | Unstructured and mutable |
+|Predictability | Synchronous | Asynchronous |
+|[Form validation](#validation) | Functions | Directives |
 
-## Common foundation
+### Scalability
 
-Both reactive and template-driven forms share underlying building blocks.
+If forms are a central part of your application, scalability is very important. Being able to reuse form models across components is critical.
 
+Reactive forms are more scalable than template-driven forms. They provide direct access to the underlying form API, and synchronous access to the form data model, making creating large-scale forms easier.
+Reactive forms require less setup for testing, and testing does not require deep understanding of change detection to properly test form updates and validation.
+
+Template-driven forms focus on simple scenarios and are not as reusable.
+They abstract away the underlying form API, and provide only asynchronous access to the form data model.
+The abstraction of template-driven forms also affects testing.
+Tests are deeply reliant on manual change detection execution to run properly, and require more setup.
+
+{@a setup}
+
+## Setting up the form model
+
+Both reactive and template-driven forms track value changes between the form input elements that users interact with and the form data in your component model.
+The two approaches share underlying building blocks, but differ in how you create and manage the common form-control instances.
+
+### Common form foundation classes
+
+Both reactive and template-driven forms are built on the following base classes.
 
 * `FormControl` tracks the value and validation status of an individual form control.
 
@@ -50,59 +71,59 @@ Both reactive and template-driven forms share underlying building blocks.
 
 * `ControlValueAccessor` creates a bridge between Angular `FormControl` instances and native DOM elements.
 
-See the [Form model setup](#setup-the-form-model) section below for an introduction to how these control instances are created and managed with reactive and template-driven forms. Further details are provided in the [data flow section](#data-flow-in-forms) of this guide.
-
 {@a setup-the-form-model}
 
-## Form model setup
-
-Reactive and template-driven forms both use a form model to track value changes between Angular forms and form input elements. The examples below show how the form model is defined and created.
-
 ### Setup in reactive forms
 
-Here's a component with an input field for a single control implemented using reactive forms.
+With reactive forms, you define the form model directly in the component class.
+The `[formControl]` directive links the explicitly created `FormControl` instance to a specific form element in the view, using an internal value accessor.
+
+The following component implements an input field for a single control, using reactive forms. In this example, the form model is the `FormControl` instance.
 
 <code-example path="forms-overview/src/app/reactive/favorite-color/favorite-color.component.ts">
 </code-example>
 
-The source of truth provides the value and status of the form element at a given point in time. In reactive forms, the form model is the source of truth. In the example above, the form model is the `FormControl` instance.
+Figure 1 shows how, in reactive forms, the form model is the source of truth; it provides the value and status of the form element at any given point in time, through the `[formControl]` directive on the input element.
+
+**Figure 1.** *Direct access to forms model in a reactive form.*
 
 <div class="lightbox">
   <img src="generated/images/guide/forms-overview/key-diff-reactive-forms.png" alt="Reactive forms key differences">
 </div>
 
-With reactive forms, the form model is explicitly defined in the component class. The reactive form directive (in this case, `FormControlDirective`) then links the existing `FormControl` instance to a specific form element in the view using a value accessor (`ControlValueAccessor` instance).
-
 ### Setup in template-driven forms
 
-Here's the same component with an input field for a single control implemented using template-driven forms.
+In template-driven forms, the form model is implicit, rather than explicit. The directive `NgModel` creates and manages a `FormControl` instance for a given form element.
+
+The following component implements the same input field for a single control, using template-driven forms.
 
 <code-example path="forms-overview/src/app/template/favorite-color/favorite-color.component.ts">
 </code-example>
 
-In template-driven forms, the source of truth is the template.
+In a template-driven form the source of truth is the template. You do not have direct programmatic access to the `FormControl` instance, as shown in Figure 2.
+
+**Figure 2.** *Indirect access to forms model in a template-driven form.*
 
 <div class="lightbox">
   <img src="generated/images/guide/forms-overview/key-diff-td-forms.png" alt="Template-driven forms key differences">
 </div>
 
-The abstraction of the form model promotes simplicity over structure. The template-driven form directive `NgModel` is responsible for creating and managing the `FormControl` instance for a given form element. It's less explicit, but you no longer have direct control over the form model.
-
 {@a data-flow-in-forms}
 
 ## Data flow in forms
 
-When building forms in Angular, it's important to understand how the framework handles data flowing from the user or from programmatic changes. Reactive and template-driven forms follow two different strategies when handling form input. The data flow examples below begin with the favorite color input field example from above, and then show how changes to favorite color are handled in reactive forms compared to template-driven forms.
+When an application contains a form, Angular must keep the view in sync with the component model and the component model in sync with the view.
+As users change values and make selections through the view, the new values must be reflected in the data model.
+Similarly, when the program logic changes values in the data model, those values must be reflected in the view.
+
+Reactive and template-driven forms differ in how they handle data flowing from the user or from programmatic changes.
+The following diagrams illustrate both kinds of data flow for each type of form, using the a favorite-color input field defined above.
 
 ### Data flow in reactive forms
 
-As described above, in reactive forms each form element in the view is directly linked to a form model (`FormControl` instance). Updates from the view to the model and from the model to the view are synchronous and aren't dependent on the UI rendered. The diagrams below use the same favorite color example to demonstrate how data flows when an input field's value is changed from the view and then from the model.
+In reactive forms each form element in the view is directly linked to the form model (a `FormControl` instance). Updates from the view to the model and from the model to the view are synchronous and do not depend on how the UI is rendered.
 
-<div class="lightbox">
-  <img src="generated/images/guide/forms-overview/dataflow-reactive-forms-vtm.png" alt="Reactive forms data flow - view to model" width="100%">
-</div>
-
-The steps below outline the data flow from view to model.
+The view-to-model diagram shows how data flows when an input field's value is changed from the view through the following steps.
 
 1. The user types a value into the input element, in this case the favorite color *Blue*.
 1. The form input element emits an "input" event with the latest value.
@@ -111,25 +132,25 @@ The steps below outline the data flow from view to model.
 1. Any subscribers to the `valueChanges` observable receive the new value.
 
 <div class="lightbox">
-  <img src="generated/images/guide/forms-overview/dataflow-reactive-forms-mtv.png" alt="Reactive forms data flow - model to view" width="100%">
+  <img src="generated/images/guide/forms-overview/dataflow-reactive-forms-vtm.png" alt="Reactive forms data flow - view to model">
 </div>
 
-The steps below outline the data flow from model to view.
+The model-to-view diagram shows how a programmatic change to the model is propagated to the view through the following steps.
 
 1. The user calls the `favoriteColorControl.setValue()` method, which updates the `FormControl` value.
 1. The `FormControl` instance emits the new value through the `valueChanges` observable.
 1. Any subscribers to the `valueChanges` observable receive the new value.
 1. The control value accessor on the form input element updates the element with the new value.
 
-### Data flow in template-driven forms
-
-In template-driven forms, each form element is linked to a directive that manages the form model internally. The diagrams below use the same favorite color example to demonstrate how data flows when an input field's value is changed from the view and then from the model.
-
 <div class="lightbox">
-  <img src="generated/images/guide/forms-overview/dataflow-td-forms-vtm.png" alt="Template-driven forms data flow - view to model" width="100%">
+  <img src="generated/images/guide/forms-overview/dataflow-reactive-forms-mtv.png" alt="Reactive forms data flow - model to view">
 </div>
 
-The steps below outline the data flow from view to model when the input value changes from *Red* to *Blue*.
+### Data flow in template-driven forms
+
+In template-driven forms, each form element is linked to a directive that manages the form model internally.
+
+The view-to-model diagram shows how data flows when an input field's value is changed from the view through the following steps.
 
 1. The user types *Blue* into the input element.
 1. The input element emits an "input" event with the value *Blue*.
@@ -141,10 +162,10 @@ The steps below outline the data flow from view to model when the input value ch
 is updated to the value emitted by the `ngModelChange` event (*Blue*).
 
 <div class="lightbox">
-  <img src="generated/images/guide/forms-overview/dataflow-td-forms-mtv.png" alt="Template-driven forms data flow - model to view" width="100%">
+  <img src="generated/images/guide/forms-overview/dataflow-td-forms-vtm.png" alt="Template-driven forms data flow - view to model" width="100%">
 </div>
 
-The steps below outline the data flow from model to view when the `favoriteColor` changes from *Blue* to *Red*.
+The model-to-view diagram shows how data flows from model to view when the `favoriteColor` changes from *Blue* to *Red*, through the following steps
 
 1. The `favoriteColor` value is updated in the component.
 1. Change detection begins.
@@ -156,6 +177,30 @@ The steps below outline the data flow from model to view when the `favoriteColor
 1. Any subscribers to the `valueChanges` observable receive the new value.
 1. The control value accessor updates the form input element in the view with the latest `favoriteColor` value.
 
+<div class="lightbox">
+  <img src="generated/images/guide/forms-overview/dataflow-td-forms-mtv.png" alt="Template-driven forms data flow - model to view" width="100%">
+</div>
+
+### Mutability of the data model
+
+The change-tracking method plays a role in the efficiency of your application.
+
+* **Reactive forms** keep the data model pure by providing it as an immutable data structure.
+Each time a change is triggered on the data model, the `FormControl` instance returns a new data model rather than updating the existing data model.
+This gives you the ability to track unique changes to the data model through the control's observable.
+Change detection is more efficient because it only needs to update on unique changes.
+Because data updates follow reactive patterns, you can integrate with observable operators to transform data.
+
+* **Template-driven** forms rely on mutability with two-way data binding to update the data model in the component as changes are made in the template.
+Because there are no unique changes to track on the data model when using two-way data binding, change detection is less efficient at determining when updates are required.
+
+The difference is demonstrated in the previous examples that use the favorite-color input element.
+
+* With reactive forms, the **`FormControl` instance** always returns a new value when the control's value is updated.
+
+* With template-driven forms, the **favorite color property** is always modified to its new value.
+
+{@a validation}
 ## Form validation
 
 Validation is an integral part of managing any set of forms. Whether you're checking for required fields or querying an external API for an existing username, Angular provides a set of built-in validators as well as the ability to create custom validators.
@@ -167,36 +212,37 @@ For more information, see [Form Validation](guide/form-validation).
 
 ## Testing
 
-Testing plays a large part in complex applications and a simpler testing strategy is useful when validating that your forms function correctly. Reactive forms and template-driven forms have different levels of reliance on rendering the UI to perform assertions based on form control and form field changes. The following examples demonstrate the process of testing forms with reactive and template-driven forms.
+Testing plays a large part in complex applications. A simpler testing strategy is useful when validating that your forms function correctly.
+Reactive forms and template-driven forms have different levels of reliance on rendering the UI to perform assertions based on form control and form field changes.
+The following examples demonstrate the process of testing forms with reactive and template-driven forms.
 
 ### Testing reactive forms
 
-Reactive forms provide a relatively easy testing strategy because they provide synchronous access to the form and data models, and they can be tested without rendering the UI. In these tests, status and data are queried and manipulated through the control without interacting with the change detection cycle.
+Reactive forms provide a relatively easy testing strategy because they provide synchronous access to the form and data models, and they can be tested without rendering the UI.
+In these tests, status and data are queried and manipulated through the control without interacting with the change detection cycle.
 
-The following tests use the favorite color components mentioned earlier to verify the data flows from view to model and model to view for a reactive form.
+The following tests use the favorite-color components from previous examples to verify the view-to-model and model-to-view data flows for a reactive form.
 
-The following test verifies the data flow from view to model.
+**Verifying view-to-model data flow**
 
-<code-example path="forms-overview/src/app/reactive/favorite-color/favorite-color.component.spec.ts" region="view-to-model" header="Favorite color test - view to model">
-</code-example>
-
-Here are the steps performed in the view to model test.
+The first example performs the following steps to verify the view-to-model data flow.
 
 1. Query the view for the form input element, and create a custom "input" event for the test.
 1. Set the new value for the input to *Red*, and dispatch the "input" event on the form input element.
 1. Assert that the component's `favoriteColorControl` value matches the value from the input.
 
-The following test verifies the data flow from model to view.
-
-<code-example path="forms-overview/src/app/reactive/favorite-color/favorite-color.component.spec.ts" region="model-to-view" header="Favorite color test - model to view">
+<code-example path="forms-overview/src/app/reactive/favorite-color/favorite-color.component.spec.ts" region="view-to-model" header="Favorite color test - view to model">
 </code-example>
 
-Here are the steps performed in the model to view test.
+The next example performs the following steps to verify the model-to-view data flow.
 
 1. Use the `favoriteColorControl`, a `FormControl` instance, to set the new value.
 1. Query the view for the form input element.
 1. Assert that the new value set on the control matches the value in the input.
 
+<code-example path="forms-overview/src/app/reactive/favorite-color/favorite-color.component.spec.ts" region="model-to-view" header="Favorite color test - model to view">
+</code-example>
+
 ### Testing template-driven forms
 
 Writing tests with template-driven forms requires a detailed knowledge of the change detection process and an understanding of how directives run on each cycle to ensure that elements are queried, tested, or changed at the correct time.
@@ -228,46 +274,17 @@ Here are the steps performed in the model to view test.
 1. Query the view for the form input element.
 1. Assert that the input value matches the value of the `favoriteColor` property in the component instance.
 
-## Mutability
-
-The change tracking method plays a role in the efficiency of your application.
-
-
-* **Reactive forms** keep the data model pure by providing it as an immutable data structure. Each time a change is triggered on the data model, the `FormControl` instance returns a new data model rather than updating the existing data model. This gives you the ability to track unique changes to the data model through the control's observable. This provides one way for change detection to be more efficient because it only needs to update on unique changes. It also follows reactive patterns that integrate with observable operators to transform data.
-
-* **Template-driven** forms rely on mutability with two-way data binding to update the data model in the component as changes are made in the template. Because there are no unique changes to track on the data model when using two-way data binding, change detection is less efficient at determining when updates are required.
-
-The difference is demonstrated in the examples above using the **favorite color** input element.
-
-
-* With reactive forms, the **`FormControl` instance** always returns a new value when the control's value is updated.
-
-* With template-driven forms, the **favorite color property** is always modified to its new value.
-
-## Scalability
-
-If forms are a central part of your application, scalability is very important. Being able to reuse form models across components is critical.
-
-
-* **Reactive forms** provide access to low-level APIs and synchronous access to the form model, making creating large-scale forms easier.
-
-* **Template-driven** forms focus on simple scenarios, are not as reusable, abstract away the low-level APIs, and provide asynchronous access to the form model. The abstraction with template-driven forms also surfaces in testing, where testing reactive forms requires less setup and no dependence on the change detection cycle when updating and validating the form and data models during testing.
-
-## Final thoughts
-
-Choosing a strategy begins with understanding the strengths and weaknesses of the options presented. Low-level API and form model access, predictability, mutability, straightforward validation and testing strategies, and scalability are all important considerations in choosing the infrastructure you use to build your forms in Angular. Template-driven forms are similar to patterns in AngularJS, but they have limitations given the criteria of many modern, large-scale Angular apps. Reactive forms minimize these limitations. Reactive forms integrate with reactive patterns already present in other areas of the Angular architecture, and complement those requirements well.
 
 ## Next steps
 
-
-
 To learn more about reactive forms, see the following guides:
 
-* [Reactive Forms](guide/reactive-forms)
-* [Form Validation](guide/form-validation#reactive-form-validation)
-* [Dynamic Forms](guide/dynamic-form)
+* [Reactive forms](guide/reactive-forms)
+* [Form validation](guide/form-validation#reactive-form-validation)
+* [Dynamic forms](guide/dynamic-form)
 
 To learn more about template-driven forms, see the following guides:
 
-* [Template-driven Forms](guide/forms#template-driven-forms)
-* [Form Validation](guide/form-validation#template-driven-validation)
+* [Building a template-driven form](guide/forms) tutorial
+* [Form validation](guide/form-validation#template-driven-validation)
+* `NgForm` directive API reference

aio/content/guide/forms.md

@@ -1,389 +1,234 @@
-# Template-driven forms
-
-Forms are the mainstay of business applications.
-You use forms to log in, submit a help request, place an order, book a flight,
-schedule a meeting, and perform countless other data-entry tasks.
-
-In developing a form, it's important to create a data-entry experience that guides the
-user efficiently and effectively through the workflow.
-
-<div class="alert is-helpful">
-
-  For the sample app that this page describes, see the <live-example></live-example>.
-
-</div>
-
-## Introduction to Template-driven forms
-
-Developing forms requires design skills (which are out of scope for this page), as well as framework support for
-*two-way data binding, change tracking, validation, and error handling*,
-which you'll learn about on this page.
-
-This page shows you how to build a simple form from scratch. Along the way you'll learn how to:
-
-* Build an Angular form with a component and template.
-* Use `ngModel` to create two-way data bindings for reading and writing input-control values.
-* Track state changes and the validity of form controls.
-* Provide visual feedback using special CSS classes that track the state of the controls.
-* Display validation errors to users and enable/disable form controls.
-* Share information across HTML elements using template reference variables.
+# Building a template-driven form
 
 {@a template-driven}
 
-You can build forms by writing templates in the Angular [template syntax](guide/template-syntax) with
-the form-specific directives and techniques described in this page.
+This tutorial shows you how to create a template-driven form whose control elements are bound to data properties, with input validation to maintain data integrity and styling to improve the user experience.
+
+Template-driven forms use [two-way data binding](guide/architecture-components#data-binding "Intro to 2-way data binding") to update the data model in the component as changes are made in the template and vice versa.
 
 <div class="alert is-helpful">
 
-  You can also use a reactive (or model-driven) approach to build forms.
-  However, this page focuses on template-driven forms.
+Angular supports two design approaches for interactive forms. You can build forms by writing templates using Angular [template syntax and directives](guide/glossary#template "Definition of template terms") with the form-specific directives and techniques described in this tutorial, or you can use a reactive (or model-driven) approach to build forms.
+
+Template-driven forms are suitable for small or simple forms, while reactive forms are more scalable and suitable for complex forms.
+For a comparison of the two approaches, see [Introduction to Forms](guide/forms-overview "Overview of Angular forms.")
 
 </div>
 
-You can build almost any form with an Angular template&mdash;login forms, contact forms, and pretty much any business form.
-You can lay out the controls creatively, bind them to data, specify validation rules and display validation errors,
+You can build almost any kind of form with an Angular template&mdash;login forms, contact forms, and pretty much any business form.
+You can lay out the controls creatively and bind them to the data in your object model.
+You can specify validation rules and display validation errors,
 conditionally enable or disable specific controls, trigger built-in visual feedback, and much more.
 
-Angular makes the process easy by handling many of the repetitive, boilerplate tasks you'd
-otherwise wrestle with yourself.
+This tutorial shows you how to build a form from scratch, using a simplified sample form like the one from the [Tour of Heroes tutorial](tutorial "Tour of Heroes") to illustrate the techniques.
 
-You'll learn to build a template-driven form that looks like this:
+<div class="alert is-helpful">
+
+  Run or download the example app: <live-example></live-example>.
+
+</div>
+
+## Objectives
+
+This tutorial teaches you how to do the following:
+
+* Build an Angular form with a component and template.
+* Use `ngModel` to create two-way data bindings for reading and writing input-control values.
+* Provide visual feedback using special CSS classes that track the state of the controls.
+* Display validation errors to users and enable or disable form controls based on the form status.
+* Share information across HTML elements using [template reference variables](guide/template-syntax#template-reference-variables-var).
+
+## Prerequisites
+
+Before going further into template-driven forms, you should have a basic understanding of the following.
+
+* TypeScript and HTML5 programming.
+* Angular app-design fundamentals, as described in [Angular Concepts](guide/architecture "Introduction to Angular concepts.").
+* The basics of [Angular template syntax](guide/template-syntax "Template syntax guide").
+* The form-design concepts that are presented in [Introduction to Forms](guide/forms-overview "Overview of Angular forms.").
+
+{@a intro}
+
+## Build a template-driven form
+
+Template-driven forms rely on directives defined in the `FormsModule`.
+
+* The `NgModel` directive reconciles value changes in the attached form element with changes in the data model, allowing you to respond to user input with input validation and error handling.
+
+* The `NgForm` directive creates a top-level `FormGroup` instance and binds it to a `<form>` element to track aggregated form value and validation status.
+As soon as you import `FormsModule`, this directive becomes active by default on all `<form>` tags. You don't need to add a special selector.
+
+* The `NgModelGroup` directive creates and binds a `FormGroup` instance to a DOM element.
+
+### The sample application
+
+The sample form in this guide is used by the *Hero Employment Agency* to maintain personal information about heroes.
+Every hero needs a job. This form helps the agency match the right hero with the right crisis.
 
 <div class="lightbox">
   <img src="generated/images/guide/forms/hero-form-1.png" alt="Clean Form">
 </div>
 
-The *Hero Employment Agency* uses this form to maintain personal information about heroes.
-Every hero needs a job. It's the company mission to match the right hero with the right crisis.
+The form highlights some design features that make it easier to use. For instance, the two required fields have a green bar on the left to make them easy to spot. These fields have initial values, so the form is valid and the **Submit** button is enabled.
 
-Two of the three fields on this form are required. Required fields have a green bar on the left to make them easy to spot.
-
-If you delete the hero name, the form displays a validation error in an attention-grabbing style:
+As you work with this form, you will learn how to include validation logic, how to customize the presentation with standard CSS, and how to handle error conditions to ensure valid input.
+If the user deletes the hero name, for example, the form becomes invalid. The app detects the changed status, and displays a validation error in an attention-grabbing style.
+In addition, the **Submit** button is disabled, and the "required" bar to the left of the input control changes from green to red.
 
 <div class="lightbox">
   <img src="generated/images/guide/forms/hero-form-2.png" alt="Invalid, Name Required">
 </div>
 
-Note that the *Submit* button is disabled, and the "required" bar to the left of the input control changes from green to red.
+### Step overview
 
-<div class="alert is-helpful">
+In the course of this tutorial, you bind a sample form to data and handle user input using the following steps.
 
-  You can customize the colors and location of the "required" bar with standard CSS.
+1. Build the basic form.
+   * Define a sample data model.
+   * Include required infrastructure such as the `FormsModule`.
+2. Bind form controls to data properties using the `ngModel` directive and two-way data-binding syntax.
+   * Examine how `ngModel` reports control states using CSS classes.
+   * Name controls to make them accessible to `ngModel`.
+3. Track input validity and control status using `ngModel`.
+   * Add custom CSS to provide visual feedback on the status.
+   * Show and hide validation-error messages.
+4. Respond to a native HTML button-click event by adding to the model data.
+5. Handle form submission using the [`ngSubmit`(api/forms/NgForm#properties)] output property of the form.
+   * Disable the **Submit** button until the form is valid.
+   * After submit, swap out the finished form for different content on the page.
 
-</div>
+{@a step1}
 
-You'll build this form in small steps:
+## Build the form
 
-1. Create the `Hero` model class.
-1. Create the component that controls the form.
-1. Create a template with the initial form layout.
-1. Bind data properties to each form control using the `ngModel` two-way data-binding syntax.
-1. Add a `name` attribute to each form-input control.
-1. Add custom CSS to provide visual feedback.
-1. Show and hide validation-error messages.
-1. Handle form submission with *ngSubmit*.
-1. Disable the form’s *Submit* button until the form is valid.
+You can recreate the sample application from the code provided here, or you can examine or download the <live-example></live-example>.
 
-## Setup
+1. The provided sample application creates the `Hero` class which defines the data model reflected in the form.
 
-Create a new project named <code>angular-forms</code>:
+   <code-example path="forms/src/app/hero.ts" header="src/app/hero.ts"></code-example>
 
-<code-example language="sh" class="code-shell">
+2. The form layout and details are defined in the `HeroFormComponent` class.
 
-  ng new angular-forms
+   <code-example path="forms/src/app/hero-form/hero-form.component.ts" header="src/app/hero-form/hero-form.component.ts (v1)" region="v1"></code-example>
 
-</code-example>
+   The component's `selector` value of "app-hero-form" means you can drop this form in a parent
+template using the `<app-hero-form>` tag.
 
-## Create the Hero model class
+3. The following code creates a new hero instance, so that the initial form can show an example hero.
 
-As users enter form data, you'll capture their changes and update an instance of a model.
-You can't lay out the form until you know what the model looks like.
+   <code-example path="forms/src/app/hero-form/hero-form.component.ts" region="SkyDog"></code-example>
 
-A model can be as simple as a "property bag" that holds facts about a thing of application importance.
-That describes well the `Hero` class with its three required fields (`id`, `name`, `power`)
-and one optional field (`alterEgo`).
+   This demo uses dummy data for `model` and `powers`. In a real app, you would inject a data service to get and save real data, or expose these properties as inputs and outputs.
 
-Using the Angular CLI command [`ng generate class`](cli/generate), generate a new class named `Hero`:
+4. The application enables the Forms feature and registers the created form component.
 
-<code-example language="sh" class="code-shell">
+   <code-example path="forms/src/app/app.module.ts" header="src/app/app.module.ts"></code-example>
 
-  ng generate class Hero
+5. The form is displayed in the application layout defined by the root component's template.
 
-</code-example>
+   <code-example path="forms/src/app/app.component.html" header="src/app/app.component.html"></code-example>
 
-With this content:
+   The initial template defines the layout for a form with two form groups and a submit button.
+   The form groups correspond to two properties of the Hero data model, name and alterEgo. Each group has a label and a box for user input.
 
-<code-example path="forms/src/app/hero.ts" header="src/app/hero.ts"></code-example>
+   * The **Name** `<input>` control element has the HTML5 `required` attribute.
+   * The **Alter Ego** `<input>` control element does not because `alterEgo` is optional.
 
-It's an anemic model with few requirements and no behavior. Perfect for the demo.
+   The **Submit** button has some classes on it for styling.
+   At this point, the form  layout is all plain HTML5, with no bindings or directives.
 
-The TypeScript compiler generates a public field for each `public` constructor parameter and
-automatically assigns the parameter’s value to that field when you create heroes.
+6. The sample form uses some style classes from [Twitter Bootstrap](http://getbootstrap.com/css/): `container`, `form-group`, `form-control`, and `btn`.
+   To use these styles, the app's style sheet imports the library.
 
-The `alterEgo` is optional, so the constructor lets you omit it; note the question mark (?) in `alterEgo?`.
+   <code-example path="forms/src/styles.1.css" header="src/styles.css"></code-example>
 
-You can create a new hero like this:
+7. The form makes the hero applicant choose one superpower from a fixed list of agency-approved powers.
+   The predefined list of `powers` is part of the data model, maintained internally in `HeroFormComponent`.
+   The Angular [NgForOf directive](api/common/NgForOf "API reference") iterates over the data values to populate the `<select>` element.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.ts" region="SkyDog"></code-example>
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (powers)" region="powers"></code-example>
 
-## Create a form component
-
-An Angular form has two parts: an HTML-based _template_ and a component _class_
-to handle data and user interactions programmatically.
-Begin with the class because it states, in brief, what the hero editor can do.
-
-Using the Angular CLI command [`ng generate component`](cli/generate), generate a new component named `HeroForm`:
-
-<code-example language="sh" class="code-shell">
-
-  ng generate component HeroForm
-
-</code-example>
-
-With this content:
-
-<code-example path="forms/src/app/hero-form/hero-form.component.ts" header="src/app/hero-form/hero-form.component.ts (v1)" region="v1"></code-example>
-
-There’s nothing special about this component, nothing form-specific,
-nothing to distinguish it from any component you've written before.
-
-Understanding this component requires only the Angular concepts covered in previous pages.
-
-* The code imports the Angular core library and the `Hero` model you just created.
-* The `@Component` selector value of "app-hero-form" means you can drop this form in a parent
-template with a `<app-hero-form>` tag.
-* The `templateUrl` property points to a separate file for the template HTML.
-* You defined dummy data for `model` and `powers`, as befits a demo.
-
-Down the road, you can inject a data service to get and save real data
-or perhaps expose these properties as inputs and outputs
-(see [Input and output properties](guide/template-syntax#inputs-outputs) on the
-[Template Syntax](guide/template-syntax) page) for binding to a
-parent component. This is not a concern now and these future changes won't affect the form.
-
-* You added a `diagnostic` property to return a JSON representation of the model.
-It'll help you see what you're doing during development; you've left yourself a cleanup note to discard it later.
-
-## Revise *app.module.ts*
-
-`app.module.ts` defines the application's root module. In it you identify the external modules you'll use in the application
-and declare the components that belong to this module, such as the `HeroFormComponent`.
-
-Because template-driven forms are in their own module, you need to add the `FormsModule` to the array of
-`imports` for the application module before you can use forms.
-
-Update it with the following:
-
-<code-example path="forms/src/app/app.module.ts" header="src/app/app.module.ts"></code-example>
-
-<div class="alert is-helpful">
-
-  There are two changes:
-
-  1. You import `FormsModule`.
-
-  1. You add the `FormsModule` to the list of `imports` defined in the `@NgModule` decorator. This gives the application
-  access to all of the template-driven forms features, including `ngModel`.
-
-</div>
-
-<div class="alert is-important">
-
-  If a component, directive, or pipe belongs to a module in the `imports` array, ​_don't_​ re-declare it in the `declarations` array.
-  If you wrote it and it should belong to this module, ​_do_​ declare it in the `declarations` array.
-
-</div>
-
-## Revise *app.component.html*
-
-`AppComponent` is the application's root component. It will host the new `HeroFormComponent`.
-
-Replace the contents of its template with the following:
-
-<code-example path="forms/src/app/app.component.html" header="src/app/app.component.html"></code-example>
-
-<div class="alert is-helpful">
-
-  There are only two changes.
-  The `template` is simply the new element tag identified by the component's `selector` property.
-  This displays the hero form when the application component is loaded.
-  Don't forget to remove the `name` field from the class body as well.
-
-</div>
-
-## Create an initial HTML form template
-
-Update the template file with the following contents:
-
-<code-example path="forms/src/app/hero-form/hero-form.component.html" region="start" header="src/app/hero-form/hero-form.component.html"></code-example>
-
-The language is simply HTML5. You're presenting two of the `Hero` fields, `name` and `alterEgo`, and
-opening them up for user input in input boxes.
-
-The *Name* `<input>` control has the HTML5 `required` attribute;
-the *Alter Ego* `<input>` control does not because `alterEgo` is optional.
-
-You added a *Submit* button at the bottom with some classes on it for styling.
-
-*You're not using Angular yet*. There are no bindings or extra directives, just layout.
-
-<div class="alert is-helpful">
-
-  In template driven forms, if you've imported `FormsModule`, you don't have to do anything
-  to the `<form>` tag in order to make use of `FormsModule`. Continue on to see how this works.
-
-</div>
-
-The `container`, `form-group`, `form-control`, and `btn` classes
-come from [Twitter Bootstrap](http://getbootstrap.com/css/). These classes are purely cosmetic.
-Bootstrap gives the form a little style.
-
-<div class="callout is-important">
-
-  <header>
-    Angular forms don't require a style library
-  </header>
-
-  Angular makes no use of the `container`, `form-group`, `form-control`, and `btn` classes or
-  the styles of any external library. Angular apps can use any CSS library or none at all.
-
-</div>
-
-To add the stylesheet, open `styles.css` and add the following import line at the top:
-
-<code-example path="forms/src/styles.1.css" header="src/styles.css"></code-example>
-
-## Add powers with _*ngFor_
-
-The hero must choose one superpower from a fixed list of agency-approved powers.
-You maintain that list internally (in `HeroFormComponent`).
-
-You'll add a `select` to the
-form and bind the options to the `powers` list using `ngFor`,
-a technique seen previously in the [Displaying Data](guide/displaying-data) page.
-
-Add the following HTML *immediately below* the *Alter Ego* group:
-
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (powers)" region="powers"></code-example>
-
-This code repeats the `<option>` tag for each power in the list of powers.
-The `pow` template input variable is a different power in each iteration;
-you display its name using the interpolation syntax.
-
-{@a ngModel}
-
-## Two-way data binding with _ngModel_
-
-Running the app right now would be disappointing.
+If you run the app right now, you see the list of powers in the selection control. The input elements are not yet bound to data values or events, so they are still blank and have no behavior.
 
 <div class="lightbox">
   <img src="generated/images/guide/forms/hero-form-3.png" alt="Early form with no binding">
 </div>
 
+{@a ngModel}
 
-You don't see hero data because you're not binding to the `Hero` yet.
-You know how to do that from earlier pages.
-[Displaying Data](guide/displaying-data) teaches property binding.
-[User Input](guide/user-input) shows how to listen for DOM events with an
-event binding and how to update a component property with the displayed value.
+## Bind input controls to data properties
 
-Now you need to display, listen, and extract at the same time.
+The next step is to bind the input controls to the corresponding `Hero` properties with two-way data binding, so that they respond to user input by updating the data model, and also respond to programmatic changes in the data by updating the display.
 
-You could use the techniques you already know, but
-instead you'll use the new `[(ngModel)]` syntax, which
-makes binding the form to the model easy.
+The `ngModel` directive declared in the `FormsModule` lets you bind controls in your template-driven form to properties in your data model.
+When you include the directive using the  syntax for two-way data binding, `[(ngModel)]`, Angular can track the value and user interaction of the control and keep the view synced with the model.
 
-Find the `<input>` tag for *Name* and update it like this:
+1. Edit the template file `hero-form.component.html`.
+
+2. Find the `<input>` tag next to the **Name** label.
+
+3. Add the `ngModel` directive, using two-way data binding syntax `[(ngModel)]="..."`.
 
 <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="ngModelName-1"></code-example>
 
 <div class="alert is-helpful">
 
-  You added a diagnostic interpolation after the input tag
-  so you can see what you're doing.
-  You left yourself a note to throw it away when you're done.
+This example has a temporary diagnostic interpolation after each input tag, `{{model.name}}`, to show the current data value of the corresponding property.
+The note reminds you to remove the diagnostic lines when you have finished observing the two-way data binding at work.
 
 </div>
 
-Focus on the binding syntax: `[(ngModel)]="..."`.
+{@a ngForm}
 
-You need one more addition to display the data. Declare
-a template variable for the form. Update the `<form>` tag with
-`#heroForm="ngForm"` as follows:
+### Access the overall form status
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="template-variable"></code-example>
+When you imported the `FormsModule` in your component, Angular automatically created and attached an [NgForm](api/forms/NgForm "API reference for NgForm") directive to the `<form>` tag in the template (because `NgForm` has the selector `form` that matches `<form>` elements).
 
-The variable `heroForm` is now a reference to the `NgForm` directive that governs the form as a whole.
+To get access to the `NgForm` and the overall form status, declare a [template reference variable](guide/template-syntax#template-reference-variables-var).
 
-<div class="alert is-helpful">
+1. Edit the template file `hero-form.component.html`.
 
-  {@a ngForm}
+2. Update the `<form>` tag with a template reference variable, `#heroForm`, and set its value as follows.
 
-  ### The _NgForm_ directive
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="template-variable"></code-example>
 
-  What `NgForm` directive?
-  You didn't add an [NgForm](api/forms/NgForm) directive.
+   The `heroForm` template variable  is now a reference to the `NgForm` directive instance that governs the form as a whole.
 
-  Angular did. Angular automatically creates and attaches an `NgForm` directive to the `<form>` tag.
+3. Run the app.
 
-  The `NgForm` directive supplements the `form` element with additional features.
-  It holds the controls you created for the elements with an `ngModel` directive
-  and `name` attribute, and monitors their properties, including their validity.
-  It also has its own `valid` property which is true only *if every contained
-  control* is valid.
+4. Start typing in the **Name** input box.
 
-</div>
+  As you add and delete characters, you can see them appear and disappear from the data model.
+  For example:
 
-If you ran the app now and started typing in the *Name* input box,
-adding and deleting characters, you'd see them appear and disappear
-from the interpolated text.
-At some point it might look like this:
+   <div class="lightbox">
+     <img src="generated/images/guide/forms/ng-model-in-action.png" alt="ngModel in action">
+   </div>
 
-<div class="lightbox">
-  <img src="generated/images/guide/forms/ng-model-in-action.png" alt="ngModel in action">
-</div>
+  The diagnostic line that shows interpolated values demonstrates that values are really flowing from the input box to the model and back again.
 
-The diagnostic is evidence that values really are flowing from the input box to the model and
-back again.
+### Naming control elements
 
-<div class="alert is-helpful">
+When you use `[(ngModel)]` on an element, you must define a `name` attribute for that element.
+Angular uses the assigned name to register the element with the `NgForm` directive attached to the parent `<form>` element.
 
-  That's *two-way data binding*.
-  For more information, see
-  [Two-way binding with NgModel](guide/template-syntax#ngModel) on the
-  the [Template Syntax](guide/template-syntax) page.
+The example added a `name` attribute to the `<input>` element and set it to "name",
+which makes sense for the hero's name.
+Any unique value will do, but using a descriptive name is helpful.
 
-</div>
+1. Add similar `[(ngModel)]` bindings and `name` attributes to **Alter Ego** and **Hero Power**.
 
-Notice that you also added a `name` attribute to the `<input>` tag and set it to "name",
-which makes sense for the hero's name. Any unique value will do, but using a descriptive name is helpful.
-Defining a `name` attribute is a requirement when using `[(ngModel)]` in combination with a form.
+2. You can now remove the diagnostic messages that show interpolated values.
 
-<div class="alert is-helpful">
+3. To confirm that two-way data binding works for the entire hero model, add a new binding at the top to the component's `diagnostic` property.
 
-  Internally, Angular creates `FormControl` instances and
-  registers them with an `NgForm` directive that Angular attached to the `<form>` tag.
-  Each `FormControl` is registered under the name you assigned to the `name` attribute.
-  Read more in the previous section, [The NgForm directive](guide/forms#ngForm).
-
-</div>
-
-Add similar `[(ngModel)]` bindings and `name` attributes to *Alter Ego* and *Hero Power*.
-You'll ditch the input box binding message
-and add a new binding (at the top) to the component's `diagnostic` property.
-Then you can confirm that two-way data binding works *for the entire hero model*.
-
-After revision, the core of the form should look like this:
+After these revisions, the form template should look like the following:
 
 <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="ngModel-2"></code-example>
 
-<div class="alert is-helpful">
+* Notice that each `<input>` element has an `id` property. This is used by the `<label>` element's `for` attribute to match the label to its input control. This is a [standard HTML feature](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/label).
 
-  * Each input element has an `id` property that is used by the `label` element's `for` attribute
-  to match the label to its input control.
-  * Each input element has a `name` property that is required by Angular forms to register the control with the form.
-
-</div>
+* Each `<input>` element also has the required `name` property that Angular uses to register the control with the form.
 
 If you run the app now and change every hero model property, the form might display like this:
 
@@ -391,18 +236,15 @@ If you run the app now and change every hero model property, the form might disp
   <img src="generated/images/guide/forms/ng-model-in-action-2.png" alt="ngModel in action">
 </div>
 
-The diagnostic near the top of the form
-confirms that all of your changes are reflected in the model.
+The diagnostic near the top of the form confirms that all of your changes are reflected in the model.
 
-*Delete* the `{{diagnostic}}` binding at the top as it has served its purpose.
+4. When you have observed the effects, you can delete the `{{diagnostic}}` binding.
 
-## Track control state and validity with _ngModel_
+## Track control states
 
-Using `ngModel` in a form gives you more than just two-way data binding. It also tells
-you if the user touched the control, if the value changed, or if the value became invalid.
-
-The *NgModel* directive doesn't just track state; it updates the control with special Angular CSS classes that reflect the state.
-You can leverage those class names to change the appearance of the control.
+The `NgModel` directive on a control tracks the state of that control.
+It tells you if the user touched the control, if the value changed, or if the value became invalid.
+Angular sets special CSS classes on the control element to reflect the state, as shown in the following table.
 
 <table>
 
@@ -472,38 +314,32 @@ You can leverage those class names to change the appearance of the control.
 
 </table>
 
-Temporarily add a [template reference variable](guide/template-syntax#ref-vars) named `spy`
-to the _Name_ `<input>` tag and use it to display the input's CSS classes.
+You use these CSS classes to define the styles for your control based on its status.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="ngModelName-2"></code-example>
+### Observe control states
 
-Now run the app and look at the _Name_ input box.
-Follow these steps *precisely*:
+To see how the classes are added and removed by the framework, open the browser's developer tools and inspect the `<input>` element that represents the hero name.
 
-1. Look but don't touch.
-1. Click inside the name box, then click outside it.
-1. Add slashes to the end of the name.
-1. Erase the name.
+1. Using your browser's developer tools, find the  `<input>` element that corresponds to the **Name** input box.
+   You can see that the element has multiple CSS classes in addition to "form-control".
 
-The actions and effects are as follows:
+2. When you first bring it up, the classes indicate that it has a valid value, that the value has not been changed since initialization or reset, and that the control has not been visited since initialization or reset.
 
-<div class="lightbox">
-  <img src="generated/images/guide/forms/control-state-transitions-anim.gif" alt="Control State Transition">
-</div>
+   ```
+   <input ... class="form-control ng-untouched ng-pristine ng-valid" ...>
+   ```
 
-You should see the following transitions and class names:
+3. Take the following actions on the **Name** `<input>` box, and observe which classes appear.
+   * Look but don't touch. The classes indicate that it is untouched, pristine, and valid.
+   * Click inside the name box, then click outside it. The control has now been visited, and the element has the `ng-touched` class instead of the `ng-untouched` class.
+   * Add slashes to the end of the name. It is now touched and dirty.
+   * Erase the name. This makes the value invalid, so the `ng-invalid` class replaces the `ng-valid` class.
 
-<div class="lightbox">
-  <img src="generated/images/guide/forms/ng-control-class-changes.png" alt="Control state transitions">
-</div>
+### Create visual feedback for states
 
-The `ng-valid`/`ng-invalid` pair is the most interesting, because you want to send a
-strong visual signal when the values are invalid. You also want to mark required fields.
-To create such visual feedback, add definitions for the `ng-*` CSS classes.
-
-*Delete* the `#spy` template reference variable and the `TODO` as they have served their purpose.
-
-## Add custom CSS for visual feedback
+The `ng-valid`/`ng-invalid` pair is particularly interesting, because you want to send a
+strong visual signal when the values are invalid.
+You also want to mark required fields.
 
 You can mark required fields and invalid data at the same time with a colored bar
 on the left of the input box:
@@ -512,20 +348,25 @@ on the left of the input box:
   <img src="generated/images/guide/forms/validity-required-indicator.png" alt="Invalid Form">
 </div>
 
-You achieve this effect by adding these class definitions to a new `forms.css` file
-that you add to the project as a sibling to `index.html`:
+To change the appearance in this way, take the following steps.
 
-<code-example path="forms/src/assets/forms.css" header="src/assets/forms.css"></code-example>
+1. Add definitions for the `ng-*` CSS classes.
 
-Update the `<head>` of `index.html` to include this style sheet:
+2. Add these class definitions to a new `forms.css` file.
 
-<code-example path="forms/src/index.html" header="src/index.html (styles)" region="styles"></code-example>
+3. Add the new file to the project as a sibling to `index.html`:
 
-## Show and hide validation error messages
+   <code-example path="forms/src/assets/forms.css" header="src/assets/forms.css"></code-example>
 
-You can improve the form. The _Name_ input box is required and clearing it turns the bar red.
-That says something is wrong but the user doesn't know *what* is wrong or what to do about it.
-Leverage the control's state to reveal a helpful message.
+4. In the `index.html` file, update the `<head>` tag to include the new style sheet.
+
+   <code-example path="forms/src/index.html" header="src/index.html (styles)" region="styles"></code-example>
+
+### Show and hide validation error messages
+
+The **Name** input box is required and clearing it turns the bar red.
+That indicates that something is wrong, but the user doesn't know what is wrong or what to do about it.
+You can provide a helpful message by checking for and responding to the control's state.
 
 When the user deletes the name, the form should look like this:
 
@@ -533,166 +374,135 @@ When the user deletes the name, the form should look like this:
   <img src="generated/images/guide/forms/name-required-error.png" alt="Name required">
 </div>
 
-To achieve this effect, extend the `<input>` tag with the following:
+The **Hero Power** select box is also required, but it doesn't need this kind of error handling because the selection box already constrains the selection to valid values.
 
-* A [template reference variable](guide/template-syntax#ref-vars).
-* The "*is required*" message in a nearby `<div>`, which you'll display only if the control is invalid.
+To define and show an error message when appropriate, take the following steps.
 
-Here's an example of an error message added to the _name_ input box:
+1. Extend the `<input>` tag with a template reference variable that you can use to access the input box's Angular control from within the template. In the example, the variable is `#name="ngModel"`.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="name-with-error-msg"></code-example>
+   <div class="alert is-helpful">
 
-You need a template reference variable to access the input box's Angular control from within the template.
-Here you created a variable called `name` and gave it the value "ngModel".
+     The template reference variable (`#name`) is set to `"ngModel"` because that is the value of the [`NgModel.exportAs`](api/core/Directive#exportAs) property. This property tells Angular how to link a reference variable to a directive.
 
-<div class="alert is-helpful">
+   </div>
 
-  Why "ngModel"?
-  A directive's [exportAs](api/core/Directive) property
-  tells Angular how to link the reference variable to the directive.
-  You set `name` to `ngModel` because the `ngModel` directive's `exportAs` property happens to be "ngModel".
-
-</div>
-
-You control visibility of the name error message by binding properties of the `name`
+2. Add a `<div>` that contains a suitable error message.
+3. Show or hide the error message by binding properties of the `name`
 control to the message `<div>` element's `hidden` property.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (hidden-error-msg)" region="hidden-error-msg"></code-example>
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (hidden-error-msg)" region="hidden-error-msg"></code-example>
 
-In this example, you hide the message when the control is valid or pristine;
-"pristine" means the user hasn't changed the value since it was displayed in this form.
+4. Add a conditional error message to the _name_ input box, as in the following example.
 
-This user experience is the developer's choice. Some developers want the message to display at all times.
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="name-with-error-msg"></code-example>
+
+<div class="callout is-helpful">
+
+<header>Illustrating the "pristine" state</header>
+
+In this example, you hide the message when the control is either valid or *pristine*.
+Pristine means the user hasn't changed the value since it was displayed in this form.
 If you ignore the `pristine` state, you would hide the message only when the value is valid.
 If you arrive in this component with a new (blank) hero or an invalid hero,
 you'll see the error message immediately, before you've done anything.
 
-Some developers want the message to display only when the user makes an invalid change.
-Hiding the message while the control is "pristine" achieves that goal.
-You'll see the significance of this choice when you add a new hero to the form.
+You might want the message to display only when the user makes an invalid change.
+Hiding the message while the control is in the `pristine` state achieves that goal.
+You'll see the significance of this choice when you add a new hero to the form in the next step.
 
-The hero *Alter Ego* is optional so you can leave that be.
+</div>
 
-Hero *Power* selection is required.
-You can add the same kind of error handling to the `<select>` if you want,
-but it's not imperative because the selection box already constrains the
-power to valid values.
+## Add a new hero
 
-Now you'll add a new hero in this form.
-Place a *New Hero* button at the bottom of the form and bind its click event to a `newHero` component method.
+This exercise shows how you can respond to a native HTML button-click event by adding to the model data.
+To let form users add a new hero, you will add a **New Hero** button that responds to a click event.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" region="new-hero-button-no-reset" header="src/app/hero-form/hero-form.component.html (New Hero button)"></code-example>
+1. In the template, place a "New Hero" `<button>` element at the bottom of the form.
+2. In the component file, add the hero-creation method to the hero data model.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.ts" region="new-hero" header="src/app/hero-form/hero-form.component.ts (New Hero method)"></code-example>
+   <code-example path="forms/src/app/hero-form/hero-form.component.ts" region="new-hero" header="src/app/hero-form/hero-form.component.ts (New Hero method)"></code-example>
 
-Run the application again, click the *New Hero* button, and the form clears.
-The *required* bars to the left of the input box are red, indicating invalid `name` and `power` properties.
-That's understandable as these are required fields.
-The error messages are hidden because the form is pristine; you haven't changed anything yet.
+3. Bind the button's click event to a hero-creation method, `newHero()`.
 
-Enter a name and click *New Hero* again.
-The app displays a _Name is required_ error message.
-You don't want error messages when you create a new (empty) hero.
-Why are you getting one now?
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" region="new-hero-button-no-reset" header="src/app/hero-form/hero-form.component.html (New Hero button)"></code-example>
 
-Inspecting the element in the browser tools reveals that the *name* input box is _no longer pristine_.
-The form remembers that you entered a name before clicking *New Hero*.
-Replacing the hero object *did not restore the pristine state* of the form controls.
+4. Run the application again and click the **New Hero** button.
 
-You have to clear all of the flags imperatively, which you can do
-by calling the form's `reset()` method after calling the `newHero()` method.
+   The form clears, and the *required* bars to the left of the input box are red, indicating invalid `name` and `power` properties.
+   Notice that the error messages are hidden. This is because the form is pristine; you haven't changed anything yet.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" region="new-hero-button-form-reset" header="src/app/hero-form/hero-form.component.html (Reset the form)"></code-example>
+5. Enter a name and click **New Hero** again.
 
-Now clicking "New Hero" resets both the form and its control flags.
+   Now the app displays a _Name is required_ error message, because the input box is no longer pristine.
+   The form remembers that you entered a name before clicking **New Hero**.
+
+6. To restore the pristine state of the form controls, clear all of the flags imperatively by calling the form's `reset()` method after calling the `newHero()` method.
+
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" region="new-hero-button-form-reset" header="src/app/hero-form/hero-form.component.html (Reset the form)"></code-example>
+
+   Now clicking **New Hero** resets both the form and its control flags.
+
+<div class="alert is-helpful">
+
+See the [User Input](guide/user-input) guide for more information about listening for DOM events with an event binding and updating a corresponding component property.
+
+</div>
 
 ## Submit the form with _ngSubmit_
 
 The user should be able to submit this form after filling it in.
-The *Submit* button at the bottom of the form
-does nothing on its own, but it will
-trigger a form submit because of its type (`type="submit"`).
+The **Submit** button at the bottom of the form does nothing on its own, but it does
+trigger a form-submit event because of its type (`type="submit"`).
+To respond to this event, take the following steps.
 
-A "form submit" is useless at the moment.
-To make it useful, bind the form's `ngSubmit` event property
-to the hero form component's `onSubmit()` method:
+1. Bind the form's [`ngSubmit`](api/forms/NgForm#properties) event property to the hero-form component's `onSubmit()` method.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (ngSubmit)" region="ngSubmit"></code-example>
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (ngSubmit)" region="ngSubmit"></code-example>
 
-You'd already defined a template reference variable,
-`#heroForm`, and initialized it with the value "ngForm".
-Now, use that variable to access the form with the Submit button.
+2. Use the template reference variable, `#heroForm` to access the form that contains the **Submit** button and create an event binding.
+You will bind the form property that indicates its overall validity to the **Submit** button's `disabled` property.
 
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (submit-button)" region="submit-button"></code-example>
 
-You'll bind the form's overall validity via
-the `heroForm` variable to the button's `disabled` property
-using an event binding. Here's the code:
-
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (submit-button)" region="submit-button"></code-example>
-
-If you run the application now, you find that the button is enabled&mdash;although
+3. Run the application now. Notice that the button is enabled&mdash;although
 it doesn't do anything useful yet.
 
-Now if you delete the Name, you violate the "required" rule, which
-is duly noted in the error message.
-The *Submit* button is also disabled.
+4. Delete the **Name** value. This violates the "required" rule, so it displays the error message&emdash;and notice that it also disables the **Submit** button.
 
-Not impressed?  Think about it for a moment. What would you have to do to
-wire the button's enable/disabled state to the form's validity without Angular's help?
 
-For you, it was as simple as this:
+   You didn't have to explicitly wire the button's enabled state to the form's validity.
+   The `FormsModule` did this automatically when you defined a template reference variable on the enhanced form element, then referred to that variable in the button control.
 
-1. Define a template reference variable on the (enhanced) form element.
-2. Refer to that variable in a button many lines away.
+### Respond to form submission
 
-## Toggle two form regions (extra credit)
+To show a response to form submission, you can hide the data entry area and display something else in its place.
 
-Submitting the form isn't terribly dramatic at the moment.
-
-<div class="alert is-helpful">
-
-  An unsurprising observation for a demo. To be honest,
-  jazzing it up won't teach you anything new about forms.
-  But this is an opportunity to exercise some of your newly won
-  binding skills.
-  If you aren't interested, skip to this page's conclusion.
-
-</div>
-
-For a more strikingly visual effect,
-hide the data entry area and display something else.
-
-Wrap the form in a `<div>` and bind
+1. Wrap the entire form in a `<div>` and bind
 its `hidden` property to the `HeroFormComponent.submitted` property.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="edit-div"></code-example>
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="edit-div"></code-example>
 
-The main form is visible from the start because the
-`submitted` property is false until you submit the form,
-as this fragment from the `HeroFormComponent` shows:
+   * The main form is visible from the start because the `submitted` property is false until you submit the form, as this fragment from the `HeroFormComponent` shows:
 
-<code-example path="forms/src/app/hero-form/hero-form.component.ts" header="src/app/hero-form/hero-form.component.ts (submitted)" region="submitted"></code-example>
+      <code-example path="forms/src/app/hero-form/hero-form.component.ts" header="src/app/hero-form/hero-form.component.ts (submitted)" region="submitted"></code-example>
 
-When you click the *Submit* button, the `submitted` flag becomes true and the form disappears
-as planned.
+   * When you click the **Submit** button, the `submitted` flag becomes true and the form disappears.
 
-Now the app needs to show something else while the form is in the submitted state.
-Add the following HTML below the `<div>` wrapper you just wrote:
+2. To show something else while the form is in the submitted state, add the following HTML below the new `<div>` wrapper.
 
-<code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="submitted"></code-example>
+   <code-example path="forms/src/app/hero-form/hero-form.component.html" header="src/app/hero-form/hero-form.component.html (excerpt)" region="submitted"></code-example>
 
-There's the hero again, displayed read-only with interpolation bindings.
-This `<div>` appears only while the component is in the submitted state.
+   This `<div>`, which shows a read-only hero with interpolation bindings, appears only while the component is in the submitted state.
 
-The HTML includes an *Edit* button whose click event is bound to an expression
+   The alternative display includes an *Edit* button whose click event is bound to an expression
 that clears the `submitted` flag.
 
-When you click the *Edit* button, this block disappears and the editable form reappears.
+3. Click the *Edit* button to switch the display back to the editable form.
 
 ## Summary
 
 The Angular form discussed in this page takes advantage of the following
-framework features to provide support for data modification, validation, and more:
+framework features to provide support for data modification, validation, and more.
 
 * An Angular HTML form template.
 * A form component class with a `@Component` decorator.
@@ -700,8 +510,8 @@ framework features to provide support for data modification, validation, and mor
 * Template-reference variables such as `#heroForm` and `#name`.
 * `[(ngModel)]` syntax for two-way data binding.
 * The use of `name` attributes for validation and form-element change tracking.
-* The reference variable’s `valid` property on input controls to check if a control is valid and show/hide error messages.
-* Controlling the *Submit* button's enabled state by binding to `NgForm` validity.
+* The reference variable’s `valid` property on input controls to check if a control is valid and show or hide error messages.
+* Controlling the **Submit** button's enabled state by binding to `NgForm` validity.
 * Custom CSS classes that provide visual feedback to users about invalid controls.
 
 Here’s the code for the final version of the application:
@@ -741,4 +551,3 @@ Here’s the code for the final version of the application:
   </code-pane>
 
 </code-tabs>
-

aio/content/guide/glossary.md

@@ -950,6 +950,10 @@ Many code editors and IDEs support TypeScript either natively or with plug-ins.
 TypeScript is the preferred language for Angular development.
 Read more about TypeScript at [typescriptlang.org](http://www.typescriptlang.org/).
 
+## TypeScript configuration file
+
+A file specifies the root files and the compiler options required to compile a TypeScript project. For more information, see [TypeScript configuration](/guide/typescript-configuration).
+
 
 {@a U}
 

aio/content/guide/http.md

@@ -1,6 +1,6 @@
 # Communicating with backend services using HTTP
 
-Most front-end applications need to communicate with a server over the HTTP protocol, in order to download or upload data and accesss other back-end services.
+Most front-end applications need to communicate with a server over the HTTP protocol, in order to download or upload data and access other back-end services.
 Angular provides a simplified client HTTP API for Angular applications, the `HttpClient` service class in `@angular/common/http`.
 
 The HTTP client service offers the following major features.
@@ -63,7 +63,7 @@ Look at the `AppModule` _imports_ to see how it is configured.
 ## Requesting data from a server
 
 Use the [`HTTPClient.get()`](api/common/http/HttpClient#get) method to fetch data from a server.
-The aynchronous method sends an HTTP request, and returns an Observable that emits the requested data when the response is received.
+The asynchronous method sends an HTTP request, and returns an Observable that emits the requested data when the response is received.
 The return type varies based on the `observe` and `responseType` values that you pass to the call.
 
 The `get()` method takes two arguments; the endpoint URL from which to fetch, and an *options* object that you can use to configure the request.
@@ -805,16 +805,16 @@ The `CachingInterceptor` in the following example demonstrates this approach.
   header="app/http-interceptors/caching-interceptor.ts)">
 </code-example>
 
-* The `isCachable()` function determines if the request is cachable.
-In this sample, only GET requests to the npm package search api are cachable.
+* The `isCacheable()` function determines if the request is cacheable.
+In this sample, only GET requests to the npm package search api are cacheable.
 
-* If the request is not cachable, the interceptor simply forwards the request
+* If the request is not cacheable, the interceptor simply forwards the request
 to the next handler in the chain.
 
-* If a cachable request is found in the cache, the interceptor returns an `of()` _observable_ with
+* If a cacheable request is found in the cache, the interceptor returns an `of()` _observable_ with
 the cached response, by-passing the `next` handler (and all other interceptors downstream).
 
-* If a cachable request is not in cache, the code calls `sendRequest()`.
+* If a cacheable request is not in cache, the code calls `sendRequest()`.
 This function creates a [request clone](#immutability) without headers, because the npm API forbids them.
 The function then forwards the clone of the request to `next.handle()` which ultimately calls the server and returns the server's response.
 

aio/content/guide/ivy-compatibility.md

@@ -2,20 +2,20 @@
 
 The Angular team has worked hard to ensure Ivy is as backwards-compatible with the previous rendering engine ("View Engine") as possible.
 However, in rare cases, minor changes were necessary to ensure that the Angular's behavior was predictable and consistent, correcting issues in the View Engine implementation.
-In order to smooth the transition, we have provided [automated migrations](guide/updating-to-version-9#migrations) wherever possible so your application and library code is migrated automatically by the CLI.
+In order to smooth the transition, we have provided [automated migrations](guide/updating-to-version-10#migrations) wherever possible so your application and library code is migrated automatically by the CLI.
 That said, some applications will likely need to apply some manual updates.
 
 {@a debugging}
 ## How to debug errors with Ivy
 
-In version 9, [a few deprecated APIs have been removed](guide/updating-to-version-9#removals) and there are a [few breaking changes](guide/updating-to-version-9#breaking-changes) unrelated to Ivy.
+In version 10, [a few deprecated APIs have been removed](guide/updating-to-version-10#removals) and there are a [few breaking changes](guide/updating-to-version-10#breaking-changes) unrelated to Ivy.
 If you're seeing errors after updating to version 9, you'll first want to rule those changes out.
 
-To do so, temporarily [turn off Ivy](guide/ivy#opting-out-of-angular-ivy) in your `tsconfig.json` and re-start your app.
+To do so, temporarily [turn off Ivy](guide/ivy#opting-out-of-angular-ivy) in your `tsconfig.base.json` and re-start your app.
 
-If you're still seeing the errors, they are not specific to Ivy. In this case, you may want to consult the [general version 9 guide](guide/updating-to-version-9). If you've opted into any of the stricter type-checking settings that are new with v9, you may also want to check out the [template type-checking guide](guide/template-typecheck).
+If you're still seeing the errors, they are not specific to Ivy. In this case, you may want to consult the [general version 10 guide](guide/updating-to-version-10). If you've opted into any of the new, stricter type-checking settings, you may also want to check out the [template type-checking guide](guide/template-typecheck).
 
-If the errors are gone, switch back to Ivy by removing the changes to the `tsconfig.json` and review the list of expected changes below.
+If the errors are gone, switch back to Ivy by removing the changes to the `tsconfig.base.json` and review the list of expected changes below.
 
 {@a payload-size-debugging}
 ### Payload size debugging

aio/content/guide/lifecycle-hooks.md

@@ -495,7 +495,7 @@ for one turn of the browser's JavaScript cycle, which triggers a new change-dete
 
 #### Write lean hook methods to avoid performance problems
 
-When you run the *AfterView* sample, notice how frequently Angular calls `AfterViewChecked()`$emdash;often when there are no changes of interest.
+When you run the *AfterView* sample, notice how frequently Angular calls `AfterViewChecked()`-often when there are no changes of interest.
 Be very careful about how much logic or computation you put into one of these methods.
 
 <div class="lightbox">

aio/content/guide/migration-solution-style-tsconfig.md

@@ -0,0 +1,54 @@
+# Solution-style `tsconfig.json` migration
+
+## What does this migration do?
+
+This migration adds support to existing projects for TypeScript's new ["solution-style" tsconfig feature](https://devblogs.microsoft.com/typescript/announcing-typescript-3-9/#solution-style-tsconfig).
+
+Support is added by making two changes:
+1. Renaming the workspace-level `tsconfig.json` to `tsconfig.base.json`.
+All project [TypeScript configuration files](guide/typescript-configuration) will extend from this base which contains the common options used throughout the workspace.
+
+2. Adding the solution `tsconfig.json` file at the root of the workspace.
+This `tsconfig.json` file will only contain references to project-level TypeScript configuration files and is only used by editors/IDEs.
+
+As an example, the solution `tsconfig.json` for a new project is as follows:
+```json
+// This is a "Solution Style" tsconfig.json file, and is used by editors and TypeScript’s language server to improve development experience.
+// It is not intended to be used to perform a compilation.
+{
+  "files": [],
+  "references": [
+    {
+      "path": "./tsconfig.app.json"
+    },
+    {
+      "path": "./tsconfig.spec.json"
+    },
+    {
+      "path": "./e2e/tsconfig.json"
+    }
+  ]
+}
+```
+
+## Why is this migration necessary?
+
+Solution-style `tsconfig.json` files provide an improved editing experience and fix several long-standing defects when editing files in an IDE.
+IDEs that leverage the TypeScript language service (for example, [Visual Studio Code](https://code.visualstudio.com)), will only use TypeScript configuration files that are named `tsconfig.json`.
+In complex projects, there may be more than one compilation unit and each of these units may have different settings and options.
+
+With the Angular CLI, a project will have application code that will target a browser.
+It will also have unit tests that should not be included within the built application and that also need additional type information present (`jasmine` in this case).
+Both parts of the project also share some but not all of the code within the project.
+As a result, two separate TypeScript configuration files (`tsconfig.app.json` and `tsconfig.spec.json`) are needed to ensure that each part of the application is configured properly and that the right types are used for each part.
+Also if web workers are used within a project, an additional tsconfig (`tsconfig.worker.json`) is needed.
+Web workers use similar but incompatible types to the main browser application.
+This requires the additional configuration file to ensure that the web worker files use the appropriate types and will build successfully.
+
+While the Angular build system knows about all of these TypeScript configuration files, an IDE using TypeScript's language service does not.
+Because of this, an IDE will not be able to properly analyze the code from each part of the project and may generate false errors or make suggestions that are incorrect for certain files.
+By leveraging the new solution-style tsconfig, the IDE can now be aware of the configuration of each part of a project.
+This allows each file to be treated appropriately based on its tsconfig.
+IDE features such as error/warning reporting and auto-suggestion will operate more effectively as well.
+
+The TypeScript 3.9 release [blog post](https://devblogs.microsoft.com/typescript/announcing-typescript-3-9/#solution-style-tsconfig) also contains some additional information regarding this new feature.

aio/content/guide/migration-update-libraries-tslib.md

@@ -0,0 +1,52 @@
+# `tslib` direct dependency migration
+
+## What does this migration do?
+
+If you have any libraries within your workspace, this migration will convert `tslib` peer dependencies to direct dependencies for the libraries.
+TypeScript uses the `tslib` package to provide common helper functions used in compiled TypeScript code.
+The `tslib` version is also updated to `2.0.0` to support TypeScript 3.9.
+
+Before:
+```json
+{
+  "name": "my-lib",
+  "version": "0.0.1",
+  "peerDependencies": {
+    "@angular/common": "^9.0.0",
+    "@angular/core": "^9.0.0",
+    "tslib": "^1.12.0"
+  }
+}
+```
+
+After:
+```json
+{
+  "name": "my-lib",
+  "version": "0.0.1",
+  "peerDependencies": {
+    "@angular/common": "^9.0.0",
+    "@angular/core": "^9.0.0"
+  },
+  "dependencies": {
+    "tslib": "^2.0.0"
+  }
+}
+```
+
+## Why is this migration necessary?
+
+The [`tslib`](https://github.com/Microsoft/tslib) is a runtime library for Typescript.
+The version of this library is bound to the version of the TypeScript compiler used to compile a library.
+Peer dependencies do not accurately represent this relationship between the runtime and the compiler.
+If `tslib` remained declared as a library peer dependency, it would be possible for some Angular workspaces to get into a state where the workspace could not satisfy `tslib` peer dependency requirements for multiple libraries, resulting in build-time or run-time errors.
+
+As of TypeScript 3.9 (used by Angular v10), `tslib` version of 2.x is required to build new applications.
+However, older libraries built with previous version of TypeScript and already published to npm might need `tslib` 1.x.
+This migration makes it possible for code depending on incompatible versions of the `tslib` runtime library to remain interoperable.
+
+
+## Do I still need `tslib` as a dependency in my workspace `package.json`?
+
+Yes.
+The `tslib` dependency declared in the `package.json` file of the workspace is used to build applications within this workspace, as well as run unit tests for workspace libraries, and is required.

aio/content/guide/migration-update-module-and-target-compiler-options.md

@@ -0,0 +1,33 @@
+# Update `module` and `target` compiler options migration
+
+## What does this migration do?
+
+This migration adjusts the [`target`](https://www.typescriptlang.org/v2/en/tsconfig#target) and [`module`](https://www.typescriptlang.org/v2/en/tsconfig#module) settings within the [TypeScript configuration files](guide/typescript-configuration) for the workspace.
+The changes to each option vary based on the builder or command that uses the TypeScript configuration file.
+Unless otherwise noted, changes are only made if the existing value was not changed since the project was created.
+This process helps ensure that intentional changes to the options are kept in place.
+
+TypeScript Configuration File(s) | Changed Property | Existing Value | New Value
+------------- | ------------- | ------------- | ------------- | -------------
+`<workspace base>/tsconfig.base.json` | `"module"` | `"esnext"` | `"es2020"`
+Used in `browser` builder options (`ng build` for applications) | `"module"` | `"esnext"` | `"es2020"`
+Used in `ng-packgr` builder options (`ng build` for libraries) | `"module"` | `"esnext"` | `"es2020"`
+Used in `karma` builder options (`ng test` for applications) | `"module"` | `"esnext"` | `"es2020"`
+Used in `server` builder options (universal) | `"module"` | `"commonjs"` | _removed_
+Used in `server` builder options (universal) | `"target"` | _any_ | `"es2016"`
+Used in `protractor` builder options (`ng e2e` for applications) | `"target"` | `"es5"` | `"es2018"`
+
+## Why is this migration necessary?
+
+This migration provides improvements to the long-term supportability of projects by updating the projects to use recommended best practice compilation options.
+
+For the functionality that executes on Node.js, such as Universal and Protractor, the new settings provide performance and troubleshooting benefits as well.
+The minimum Node.js version for the Angular CLI (v10.13) supports features in ES2018 and earlier.
+By targeting later ES versions, the compiler transforms less code and can use newer features directly.
+Since zone.js does not support native `async` and `await`, the universal builds still target ES2016.
+
+## Why `"es2020"` instead of `"esnext"`?
+
+In TypeScript 3.9, the behavior of the TypeScript compiler controlled by `module` is the same with both `"esnext"` and `"es2020"` values.
+This behavior can change in the future, because the `"esnext"` option could evolve in a backwards incompatible ways, resulting in build-time or run-time errors during a TypeScript update.
+As a result, code can become unstable. Using the `"es2020"` option mitigates this risk.

aio/content/guide/npm-packages.md

@@ -118,7 +118,6 @@ Package name                               | Description
 [**@angular&#8209;devkit/<br />build&#8209;angular**](https://github.com/angular/angular-cli/) | The Angular build tools.
 [**@angular/cli**](https://github.com/angular/angular-cli/) | The Angular CLI tools.
 **@angular/<br />compiler&#8209;cli** | The Angular compiler, which is invoked by the Angular CLI's `ng build` and `ng serve` commands.
-**@angular/<br />language&#8209;service** | The [Angular language service](guide/language-service) analyzes component templates and provides type and error information that TypeScript-aware editors can use to improve the developer's experience. For example, see the [Angular language service extension for VS Code](https://marketplace.visualstudio.com/items?itemName=Angular.ng-template).
 **@types/... ** | TypeScript definition files for 3rd party libraries such as Jasmine and Node.js.
 [**codelyzer**](https://www.npmjs.com/package/codelyzer) | A linter for Angular apps whose rules conform to the Angular [style guide](guide/styleguide).
 **jasmine/... ** | Packages to support the [Jasmine](https://jasmine.github.io/) test library.
@@ -135,3 +134,4 @@ Package name                               | Description
 
  * [Building and serving](guide/build) describes how packages come together to create a development build.
  * [Deployment](guide/deployment) describes how packages come together to create a production build.
+ 

aio/content/guide/observables.md

@@ -112,7 +112,7 @@ Because observables produce values asynchronously, try/catch will not effectivel
 <code-example>
 myObservable.subscribe({
   next(num) { console.log('Next num: ' + num)},
-  error(err) { console.log('Received an errror: ' + err)}
+  error(err) { console.log('Received an error: ' + err)}
 });
 </code-example>
 

aio/content/guide/pipes.md

@@ -1,607 +1,440 @@
-# Pipes
+# Transforming Data Using Pipes
 
-Every application starts out with what seems like a simple task: get data, transform them, and show them to users.
-Getting data could be as simple as creating a local variable or as complex as streaming data over a WebSocket.
+Use [pipes](guide/glossary#pipe "Definition of a pipe") to transform and format strings, currency amounts, dates, and other display data.
+Pipes are simple functions you can use in [template expressions](/guide/glossary#template-expression "Definition of template expression") to accept an input value and return a transformed value.
+For example, you would use a pipe to show a date as **April 15, 1988** rather than the raw string format.
 
 <div class="alert is-helpful">
 
-  For the sample app that this page describes, see the <live-example></live-example>.
+  For the sample app used in this topic, see the <live-example></live-example>.
 
 </div>
 
-Once data arrives, you could push their raw `toString` values directly to the view,
-but that rarely makes for a good user experience.
-For example, in most use cases, users prefer to see a date in a simple format like
-<samp>April 15, 1988</samp> rather than the raw string format
-<samp>Fri Apr 15 1988 00:00:00 GMT-0700 (Pacific Daylight Time)</samp>.
-
-Clearly, some values benefit from a bit of editing. You may notice that you
-desire many of the same transformations repeatedly, both within and across many applications.
-You can almost think of them as styles.
-In fact, you might like to apply them in your HTML templates as you do styles.
-
-Introducing Angular pipes, a way to write display-value transformations that you can declare in your HTML.
-
-
-## Using pipes
-
-A pipe takes in data as input and transforms it to a desired output.
-In this page, you'll use pipes to transform a component's birthday property into
-a human-friendly date.
-
-
-<code-example path="pipes/src/app/hero-birthday1.component.ts" header="src/app/hero-birthday1.component.ts"></code-example>
-
-
-
-Focus on the component's template.
-
-
-<code-example path="pipes/src/app/app.component.html" region="hero-birthday-template" header="src/app/app.component.html"></code-example>
-
-
-
-Inside the interpolation expression, you flow the component's `birthday` value through the
-[pipe operator](guide/template-syntax#pipe) ( | ) to the [Date pipe](api/common/DatePipe)
-function on the right. All pipes work this way.
-
-
-
-
-## Built-in pipes
-Angular comes with a stock of pipes such as
-`DatePipe`, `UpperCasePipe`, `LowerCasePipe`, `CurrencyPipe`, and `PercentPipe`.
-They are all available for use in any template.
+Angular provides built-in pipes for typical data transformations, including transformations for internationalization (i18n), which use locale information to format data.
+The following are commonly used built-in pipes for data formatting:
 
+* [`DatePipe`](api/common/DatePipe): Formats a date value according to locale rules.
+* [`UpperCasePipe`](api/common/UpperCasePipe): Transforms text to all upper case.
+* [`LowerCasePipe`](api/common/LowerCasePipe): Transforms text to all lower case.
+* [`CurrencyPipe`](api/common/CurrencyPipe): Transforms a number to a currency string, formatted according to locale rules.
+* [`DecimalPipe`](/api/common/DecimalPipe): Transforms a number into a string with a decimal point, formatted according to locale rules.
+* [`PercentPipe`](api/common/PercentPipe): Transforms a number to a percentage string, formatted according to locale rules.
 
 <div class="alert is-helpful">
 
-
-
-Read more about these and many other built-in pipes in the [pipes topics](api?type=pipe) of the
-[API Reference](api); filter for entries that include the word "pipe".
-
-Angular doesn't have a `FilterPipe` or an `OrderByPipe` for reasons explained in the [Appendix](guide/pipes#no-filter-pipe) of this page.
-
+* For a complete list of built-in pipes, see the [pipes API documentation](/api/common#pipes "Pipes API reference summary").
+* To learn more about using pipes for internationalization (i18n) efforts, see [formatting data based on locale](/guide/i18n#i18n-pipes "Formatting data based on locale").
 
 </div>
 
+You can also create pipes to encapsulate custom transformations and use your custom pipes in template expressions.
 
+## Prerequisites
 
+To use pipes you should have a basic understanding of the following:
 
-## Parameterizing a pipe
+* [Typescript](guide/glossary#typescript "Definition of Typescript") and HTML5 programming
+* [Templates](guide/glossary#template "Definition of a template") in HTML with CSS styles
+* [Components](guide/glossary#component "Definition of a component")
 
-A pipe can accept any number of optional parameters to fine-tune its output.
-To add parameters to a pipe, follow the pipe name with a colon ( : ) and then the parameter value
-(such as `currency:'EUR'`). If the pipe accepts multiple parameters, separate the values with colons (such as `slice:1:5`)
+## Using a pipe in a template
 
-Modify the birthday template to give the date pipe a format parameter.
-After formatting the hero's April 15th birthday, it renders as **<samp>04/15/88</samp>**:
+To apply a pipe, use the pipe operator (`|`) within a template expression as shown in the following code example, along with the *name* of the pipe, which is `date` for the built-in [`DatePipe`](api/common/DatePipe).
+The tabs in the example show the following:
 
+* `app.component.html` uses `date` in a separate template to display a birthday.
+* `hero-birthday1.component.ts` uses the same pipe as part of an in-line template in a component that also sets the birthday value.
 
-<code-example path="pipes/src/app/app.component.html" region="format-birthday" header="src/app/app.component.html"></code-example>
+<code-tabs>
+  <code-pane
+    header="src/app/app.component.html"
+    region="hero-birthday-template"
+    path="pipes/src/app/app.component.html">
+  </code-pane>
+  <code-pane
+    header="src/app/hero-birthday1.component.ts"
+    path="pipes/src/app/hero-birthday1.component.ts">
+  </code-pane>
+</code-tabs>
 
+The component's `birthday` value flows through the
+[pipe operator](guide/template-syntax#pipe) ( | ) to the [`date`](api/common/DatePipe)
+function.
 
+{@a parameterizing-a-pipe}
 
-The parameter value can be any valid template expression,
-(see the [Template expressions](guide/template-syntax#template-expressions) section of the
-[Template Syntax](guide/template-syntax) page)
-such as a string literal or a component property.
-In other words, you can control the format through a binding the same way you control the birthday value through a binding.
+## Formatting data with parameters and chained pipes
 
-Write a second component that *binds* the pipe's format parameter
-to the component's `format` property. Here's the template for that component:
+Use optional parameters to fine-tune a pipe's output.
+For example, you can use the [`CurrencyPipe`](api/common/CurrencyPipe "API reference") with a country code such as EUR as a parameter.
+The template expression `{{ amount | currency:'EUR' }}` transforms the `amount` to currency in euros.
+Follow the pipe name (`currency`) with a colon (`:`) and the parameter value (`'EUR'`).
 
+If the pipe accepts multiple parameters, separate the values with colons.
+For example, `{{ amount | currency:'EUR':'Euros '}}` adds the second parameter, the string literal `'Euros '`, to the output string. You can use any valid template expression as a parameter, such as a string literal or a component property.
 
-<code-example path="pipes/src/app/hero-birthday2.component.ts" region="template" header="src/app/hero-birthday2.component.ts (template)"></code-example>
+Some pipes require at least one parameter and allow more optional parameters, such as [`SlicePipe`](/api/common/SlicePipe "API reference for SlicePipe"). For example, `{{ slice:1:5 }}` creates a new array or string containing a subset of the elements starting with element `1` and ending with element `5`.
 
+### Example: Formatting a date
 
+The tabs in the following example demonstrates toggling between two different formats (`'shortDate'` and `'fullDate'`):
 
-You also added a button to the template and bound its click event to the component's `toggleFormat()` method.
-That method toggles the component's `format` property between a short form
+* The `app.component.html` template uses a format parameter for the [`DatePipe`](api/common/DatePipe) (named `date`) to show the date as **04/15/88**.
+* The `hero-birthday2.component.ts` component binds the pipe's format parameter to the component's `format` property in the `template` section, and adds a button for a click event bound to the component's `toggleFormat()` method.
+* The `hero-birthday2.component.ts` component's `toggleFormat()` method toggles the component's `format` property between a short form
 (`'shortDate'`) and a longer form (`'fullDate'`).
 
+<code-tabs>
+  <code-pane
+    header="src/app/app.component.html"
+    region="format-birthday"
+    path="pipes/src/app/app.component.html">
+  </code-pane>
+  <code-pane
+    header="src/app/hero-birthday2.component.ts (template)"
+    region="template"
+    path="pipes/src/app/hero-birthday2.component.ts">
+  </code-pane>
+  <code-pane
+    header="src/app/hero-birthday2.component.ts (class)"
+    region="class"
+    path="pipes/src/app/hero-birthday2.component.ts">
+  </code-pane>
+</code-tabs>
 
-<code-example path="pipes/src/app/hero-birthday2.component.ts" region="class" header="src/app/hero-birthday2.component.ts (class)"></code-example>
-
-
-
-As you click the button, the displayed date alternates between
-"**<samp>04/15/1988</samp>**" and
-"**<samp>Friday, April 15, 1988</samp>**".
+Clicking the **Toggle Format** button alternates the date format between **04/15/1988** and **Friday, April 15, 1988** as shown in Figure 1.
 
 <div class="lightbox">
   <img src='generated/images/guide/pipes/date-format-toggle-anim.gif' alt="Date Format Toggle">
 </div>
 
+**Figure 1.** Clicking the button toggles the date format
 
 <div class="alert is-helpful">
 
-
-
-Read more about the `DatePipe` format options in the [Date Pipe](api/common/DatePipe)
-API Reference page.
-
+For `date` pipe format options, see [DatePipe](api/common/DatePipe "DatePipe API Reference page").
 
 </div>
 
+### Example: Applying two formats by chaining pipes
 
+You can chain pipes so that the output of one pipe becomes the input to the next.
 
-## Chaining pipes
+In the following example, chained pipes first apply a format to a date value, then convert the formatted date to uppercase characters.
+The first tab for the `src/app/app.component.html` template chains `DatePipe` and `UpperCasePipe` to display the birthday as **APR 15, 1988**.
+The second tab for the `src/app/app.component.html` template passes the `fullDate` parameter to `date` before chaining to `uppercase`, which produces **FRIDAY, APRIL 15, 1988**.
 
-You can chain pipes together in potentially useful combinations.
-In the following example, to display the birthday in uppercase,
-the birthday is chained to the `DatePipe` and on to the `UpperCasePipe`.
-The birthday displays as **<samp>APR 15, 1988</samp>**.
+<code-tabs>
+  <code-pane
+    header="src/app/app.component.html (1)"
+    region="chained-birthday"
+    path="pipes/src/app/app.component.html">
+  </code-pane>
+  <code-pane
+    header="src/app/app.component.html (2)"
+    region="chained-parameter-birthday"
+    path="pipes/src/app/app.component.html">
+  </code-pane>
+</code-tabs>
 
+{@a Custom-pipes}
 
-<code-example path="pipes/src/app/app.component.html" region="chained-birthday" header="src/app/app.component.html"></code-example>
+## Creating pipes for custom data transformations
 
+Create custom pipes to encapsulate transformations that are not provided with the built-in pipes.
+You can then use your custom pipe in template expressions, the same way you use built-in pipes—to transform input values to output values for display.
 
+### Marking a class as a pipe
 
-This example&mdash;which displays **<samp>FRIDAY, APRIL 15, 1988</samp>**&mdash;chains
-the same pipes as above, but passes in a parameter to `date` as well.
+To mark a class as a pipe and supply configuration metadata, apply the [`@Pipe`](/api/core/Pipe "API reference for Pipe") [decorator](/guide/glossary#decorator--decoration "Definition for decorator") to the class.
+Use [UpperCamelCase](guide/glossary#case-types "Definition of case types") (the general convention for class names) for the pipe class name, and [camelCase](guide/glossary#case-types "Definition of case types") for the corresponding `name` string.
+Do not use hyphens in the `name`.
+For details and more examples, see [Pipe names](guide/styleguide#pipe-names "Pipe names in the Angular coding style guide").
 
+Use `name` in template expressions as you would for a built-in pipe.
 
-<code-example path="pipes/src/app/app.component.html" region="chained-parameter-birthday" header="src/app/app.component.html"></code-example>
+<div class="alert is-important">
 
-
-
-
-## Custom pipes
-
-You can write your own custom pipes.
-Here's a custom pipe named `ExponentialStrengthPipe` that can boost a hero's powers:
-
-
-<code-example path="pipes/src/app/exponential-strength.pipe.ts" header="src/app/exponential-strength.pipe.ts"></code-example>
-
-
-
-This pipe definition reveals the following key points:
-
-* A pipe is a class decorated with pipe metadata.
-* The pipe class implements the `PipeTransform` interface's `transform` method that
-accepts an input value followed by optional parameters and returns the transformed value.
-* There will be one additional argument to the `transform` method for each parameter passed to the pipe.
-Your pipe has one such parameter: the `exponent`.
-* To tell Angular that this is a pipe, you apply the
-`@Pipe` decorator, which you import from the core Angular library.
-* The `@Pipe` decorator allows you to define the
-   pipe name that you'll use within template expressions. It must be a valid JavaScript identifier.
-   Your pipe's name is `exponentialStrength`.
-
-
-<div class="alert is-helpful">
-
-
-
-## The *PipeTransform* interface
-
-The `transform` method is essential to a pipe.
-The `PipeTransform` *interface* defines that method and guides both tooling and the compiler.
-Technically, it's optional; Angular looks for and executes the `transform` method regardless.
+* Include your pipe in the `declarations` field of the `NgModule` metadata in order for it to be available to a template. See the `app.module.ts` file in the example app (<live-example></live-example>). For details, see [NgModules](guide/ngmodules "NgModules introduction").
+* Register your custom pipes. The [Angular CLI](cli "CLI Overview and Command Reference") [`ng generate pipe`](cli/generate#pipe "ng generate pipe in the CLI Command Reference") command registers the pipe automatically.
 
 </div>
 
-Now you need a component to demonstrate the pipe.
+### Using the PipeTransform interface
 
-<code-example path="pipes/src/app/power-booster.component.ts" header="src/app/power-booster.component.ts"></code-example>
+Implement the [`PipeTransform`](/api/core/PipeTransform "API reference for PipeTransform") interface in your custom pipe class to perform the transformation.
+
+Angular invokes the `transform` method with the value of a binding as the first argument, and any parameters as the second argument in list form, and returns the transformed value.
+
+### Example: Transforming a value exponentially
+
+In a game, you may want to implement a transformation that raises a value exponentially to increase a hero's power.
+For example, if the hero's score is 2, boosting the hero's power exponentially by 10 produces a score of 1024.
+You can use a custom pipe for this transformation.
+
+The following code example shows two component definitions:
+
+* The `exponential-strength.pipe.ts` component defines a custom pipe named `exponentialStrength` with the `transform` method that performs the transformation.
+It defines an argument to the `transform` method (`exponent`) for a parameter passed to the pipe.
+
+* The `power-booster.component.ts` component demonstrates how to use the pipe, specifying a value (`2`) and the exponent parameter (`10`).
+Figure 2 shows the output.
+
+<code-tabs>
+  <code-pane
+    header="src/app/exponential-strength.pipe.ts"
+    path="pipes/src/app/exponential-strength.pipe.ts">
+  </code-pane>
+  <code-pane
+    header="src/app/power-booster.component.ts"
+    path="pipes/src/app/power-booster.component.ts">
+  </code-pane>
+</code-tabs>
 
 <div class="lightbox">
   <img src='generated/images/guide/pipes/power-booster.png' alt="Power Booster">
 </div>
 
+**Figure 2.** Output from the `exponentialStrength` pipe
 
+<div class="alert is-helpful">
 
-Note the following:
-
-* You use your custom pipe the same way you use built-in pipes.
-* You must include your pipe in the `declarations` array of the `AppModule`
-* If you choose to inject your pipe into a class, you must provide it in the `providers` array of your `NgModule`.
-
-<div class="callout is-helpful">
-
-<header>
-  Remember the declarations array
-</header>
-
-
-You must register custom pipes.
-If you don't, Angular reports an error.
-The [Angular CLI's](cli) generator registers the pipe automatically.
-
+To examine the behavior the `exponentialStrength` pipe in the <live-example></live-example>, change the value and optional exponent in the template.
 
 </div>
 
+{@a change-detection}
 
+## Detecting changes with data binding in pipes
 
-To probe the behavior in the <live-example></live-example>,
-change the value and optional exponent in the template.
-
-## Power Boost Calculator
-
-It's not much fun updating the template to test the custom pipe.
-Upgrade the example to a "Power Boost Calculator" that combines
-your pipe and two-way data binding with `ngModel`.
+You use [data binding](/guide/glossary#data-binding "Definition of data binding") with a  pipe to display values and respond to user actions.
+If the data is a primitive input value, such as `String` or `Number`, or an object reference as input, such as `Date` or `Array`, Angular executes the pipe whenever it detects a change for the input value or reference.
 
+For example, you could change the previous custom pipe example to use two-way data binding with `ngModel` to input the amount and boost factor, as shown in the following code example.
 
 <code-example path="pipes/src/app/power-boost-calculator.component.ts" header="src/app/power-boost-calculator.component.ts">
 
 </code-example>
 
-
+The `exponentialStrength` pipe executes every time the user changes the "normal power" value or the "boost factor", as shown in Figure 3.
 
 <div class="lightbox">
   <img src='generated/images/guide/pipes/power-boost-calculator-anim.gif' alt="Power Boost Calculator">
 </div>
 
+**Figure 3.** Changing the amount and boost factor for the `exponentialStrength` pipe
 
+Angular detects each change and immediately runs the pipe.
+This is fine for primitive input values.
+However, if you change something *inside* a composite object (such as the month of a date, an element of an array, or an object property), you need to understand how change detection works, and how to use an `impure` pipe.
 
+### How change detection works
 
-{@a change-detection}
+Angular looks for changes to data-bound values in a [change detection](guide/glossary#change-detection "Definition of change detection") process that runs after every DOM event: every keystroke, mouse move, timer tick, and server response.
+The following example, which doesn't use a pipe, demonstrates how Angular uses its default change detection strategy to monitor and update its display of every hero in the `heroes` array.
+The example tabs show the following:
 
+* In the `flying-heroes.component.html (v1)` template, the `*ngFor` repeater displays the hero names.
+* Its companion component class `flying-heroes.component.ts (v1)` provides heroes, adds heroes into the array, and resets the array.
 
-## Pipes and change detection
+<code-tabs>
+  <code-pane
+    header="src/app/flying-heroes.component.html (v1)"
+    region="template-1"
+    path="pipes/src/app/flying-heroes.component.html">
+  </code-pane>
+  <code-pane
+    header="src/app/flying-heroes.component.ts (v1)"
+    region="v1"
+    path="pipes/src/app/flying-heroes.component.ts">
+  </code-pane>
+</code-tabs>
 
-Angular looks for changes to data-bound values through a *change detection* process that runs after every DOM event:
-every keystroke, mouse move, timer tick, and server response. This could be expensive.
-Angular strives to lower the cost whenever possible and appropriate.
+Angular updates the display every time the user adds a hero.
+If the user clicks the **Reset** button, Angular replaces `heroes` with a new array of the original heroes and updates the display.
+If you add the ability to remove or change a hero, Angular would detect those changes and update the display as well.
 
-Angular picks a simpler, faster change detection algorithm when you use a pipe.
+However, executing a pipe to update the display with every change would slow down your app's performance.
+So Angular uses a faster change-detection algorithm for executing a pipe, as described in the next section.
 
-<h3 class="no-toc">No pipe</h3>
+{@a pure-and-impure-pipes}
 
-In the next example, the component uses the default, aggressive change detection strategy to monitor and update
-its display of every hero in the `heroes` array. Here's the template:
+### Detecting pure changes to primitives and object references
 
+By default, pipes are defined as *pure* so that Angular executes the pipe only when it detects a *pure change* to the input value.
+A pure change is either a change to a primitive input value (such as `String`, `Number`, `Boolean`, or `Symbol`), or a changed object reference (such as `Date`, `Array`, `Function`, or `Object`).
 
-<code-example path="pipes/src/app/flying-heroes.component.html" region="template-1" header="src/app/flying-heroes.component.html (v1)"></code-example>
+{@a pure-pipe-pure-fn}
 
+A pure pipe must use a pure function, which is one that processes inputs and returns values without side effects.
+In other words, given the same input, a pure function should always return the same output.
 
+With a pure pipe, Angular ignores changes within composite objects, such as a newly added element of an existing array, because checking a primitive value or object reference is much faster than performing a deep check for differences within objects.
+Angular can quickly determine if it can skip executing the pipe and updating the view.
 
-The companion component class provides heroes, adds heroes into the array, and can reset the array.
+However, a pure pipe with an array as input may not work the way you want.
+To demonstrate this issue, change the previous example to filter the list of heroes to just those heroes who can fly.
+Use the `FlyingHeroesPipe` in the `*ngFor` repeater as shown in the following code.
+The tabs for the example show the following:
 
-<code-example path="pipes/src/app/flying-heroes.component.ts" region="v1" header="src/app/flying-heroes.component.ts (v1)"></code-example>
+* The template (`flying-heroes.component.html (flyers)`) with the new pipe.
+* The `FlyingHeroesPipe` custom pipe implementation (`flying-heroes.pipe.ts`).
 
+<code-tabs>
+  <code-pane
+    header="src/app/flying-heroes.component.html (flyers)"
+    region="template-flying-heroes"
+    path="pipes/src/app/flying-heroes.component.html">
+  </code-pane>
+  <code-pane
+    header="src/app/flying-heroes.pipe.ts"
+    region="pure"
+    path="pipes/src/app/flying-heroes.pipe.ts">
+  </code-pane>
+</code-tabs>
 
-
-You can add heroes and Angular updates the display when you do.
-If you click the `reset` button, Angular replaces `heroes` with a new array of the original heroes and updates the display.
-If you added the ability to remove or change a hero, Angular would detect those changes and update the display as well.
-
-<h3 class="no-toc"><i>FlyingHeroesPipe</i></h3>
-
-Add a `FlyingHeroesPipe` to the `*ngFor` repeater that filters the list of heroes to just those heroes who can fly.
-
-<code-example path="pipes/src/app/flying-heroes.component.html" region="template-flying-heroes" header="src/app/flying-heroes.component.html (flyers)"></code-example>
-
-
-
-Here's the `FlyingHeroesPipe` implementation, which follows the pattern for custom pipes described earlier.
-
-<code-example path="pipes/src/app/flying-heroes.pipe.ts" region="pure" header="src/app/flying-heroes.pipe.ts"></code-example>
-
-
-
-Notice the odd behavior in the <live-example></live-example>:
-when you add flying heroes, none of them are displayed under "Heroes who fly."
-
-Although you're not getting the behavior you want, Angular isn't broken.
-It's just using a different change-detection algorithm that ignores changes to the list or any of its items.
-
-Notice how a hero is added:
+The app now shows unexpected behavior: When the user adds flying heroes, none of them appear under "Heroes who fly."
+This happens because the code that adds a hero does so by pushing it onto the `heroes` array:
 
 <code-example path="pipes/src/app/flying-heroes.component.ts" region="push" header="src/app/flying-heroes.component.ts"></code-example>
 
+The change detector ignores changes to elements of an array, so the pipe doesn't run.
 
+The reason Angular ignores the changed array element is that the *reference* to the array hasn't changed.
+Since the array is the same, Angular does not update the display.
 
-You add the hero into the `heroes` array. The reference to the array hasn't changed.
-It's the same array. That's all Angular cares about. From its perspective, *same array, no change, no display update*.
-
-To fix that, create an array with the new hero appended and assign that to `heroes`.
-This time Angular detects that the array reference has changed.
-It executes the pipe and updates the display with the new array, which includes the new flying hero.
-
-If you *mutate* the array, no pipe is invoked and the display isn't updated;
-if you *replace* the array, the pipe executes and the display is updated.
-The Flying Heroes application extends the
-code with checkbox switches and additional displays to help you experience these effects.
+One way to get the behavior you want is to change the object reference itself.
+You can replace the array with a new array containing the newly changed elements, and then input the new array to the pipe.
+In the above example, you can create an array with the new hero appended, and assign that to `heroes`. Angular detects the change in the array reference and executes the pipe.
 
+To summarize, if you mutate the input array, the pure pipe doesn't execute.
+If you *replace* the input array, the pipe executes and the display is updated, as shown in Figure 4.
 
 <div class="lightbox">
   <img src='generated/images/guide/pipes/flying-heroes-anim.gif' alt="Flying Heroes">
 </div>
 
+**Figure 4.** The `flyingHeroes` pipe filtering the display to flying heroes
 
+The above example demonstrates changing a component's code to accommodate a pipe.
 
-Replacing the array is an efficient way to signal Angular to update the display.
-When do you replace the array? When the data changes.
-That's an easy rule to follow in *this* example
-where the only way to change the data is by adding a hero.
-
-More often, you don't know when the data has changed,
-especially in applications that mutate data in many ways,
-perhaps in application locations far away.
-A component in such an application usually can't know about those changes.
-Moreover, it's unwise to distort the component design to accommodate a pipe.
-Strive to keep the component class independent of the HTML.
-The component should be unaware of pipes.
-
-For filtering flying heroes, consider an *impure pipe*.
-
-
-
-## Pure and impure pipes
-
-There are two categories of pipes: *pure* and *impure*.
-Pipes are pure by default. Every pipe you've seen so far has been pure.
-You make a pipe impure by setting its pure flag to false. You could make the `FlyingHeroesPipe`
-impure like this:
-
-
-<code-example path="pipes/src/app/flying-heroes.pipe.ts" region="pipe-decorator" header="src/app/flying-heroes.pipe.ts"></code-example>
-
-
-
-Before doing that, understand the difference between pure and impure, starting with a pure pipe.
-
-<h3 class="no-toc">Pure pipes</h3>
-
-Angular executes a *pure pipe* only when it detects a *pure change* to the input value.
-A pure change is either a change to a primitive input value (`String`, `Number`, `Boolean`, `Symbol`)
-or a changed object reference (`Date`, `Array`, `Function`, `Object`).
-
-Angular ignores changes within (composite) objects.
-It won't call a pure pipe if you change an input month, add to an input array, or update an input object property.
-
-This may seem restrictive but it's also fast.
-An object reference check is fast&mdash;much faster than a deep check for
-differences&mdash;so Angular can quickly determine if it can skip both the
-pipe execution and a view update.
-
-For this reason, a pure pipe is preferable when you can live with the change detection strategy.
-When you can't, you *can* use the impure pipe.
-
-
-<div class="alert is-helpful">
-
-
-
-Or you might not use a pipe at all.
-It may be better to pursue the pipe's purpose with a property of the component,
-a point that's discussed later in this page.
-
-
-</div>
-
-
-
-<h3 class="no-toc">Impure pipes</h3>
-
-Angular executes an *impure pipe*  during every component change detection cycle.
-An impure pipe is called often, as often as every keystroke or mouse-move.
-
-With that concern in mind, implement an impure pipe with great care.
-An expensive, long-running pipe could destroy the user experience.
-
+To keep your component simpler and independent of HTML templates that use pipes, you can, as an alternative, use an *impure* pipe to detect changes within composite objects such as arrays, as described in the next section.
 
 {@a impure-flying-heroes}
 
+### Detecting impure changes within composite objects
 
-<h3 class="no-toc">An impure <i>FlyingHeroesPipe</i></h3>
+To execute a custom pipe after a change *within* a composite object, such as a change to an element of an array, you need to define your pipe as `impure` to detect impure changes.
+Angular executes an impure pipe every time it detects a change with every keystroke or mouse movement.
 
-A flip of the switch turns the `FlyingHeroesPipe` into a `FlyingHeroesImpurePipe`.
-The complete implementation is as follows:
+<div class="alert is-important">
+
+While an impure pipe can be useful, be careful using one. A long-running impure pipe could dramatically slow down your app.
+
+</div>
+
+Make a pipe impure by setting its `pure` flag to `false`:
+
+<code-example path="pipes/src/app/flying-heroes.pipe.ts" region="pipe-decorator" header="src/app/flying-heroes.pipe.ts"></code-example>
+
+The following code shows the complete implementation of `FlyingHeroesImpurePipe`, which extends `FlyingHeroesPipe` to inherit its characteristics.
+The example shows that you don't have to change anything else—the only difference is setting the `pure` flag as `false` in the pipe metadata.
 
 <code-tabs>
-
-  <code-pane header="FlyingHeroesImpurePipe" path="pipes/src/app/flying-heroes.pipe.ts" region="impure">
-
+  <code-pane
+    header="src/app/flying-heroes.pipe.ts (FlyingHeroesImpurePipe)"
+    region="impure"
+    path="pipes/src/app/flying-heroes.pipe.ts">
   </code-pane>
-
-  <code-pane header="FlyingHeroesPipe" path="pipes/src/app/flying-heroes.pipe.ts" region="pure">
-
+  <code-pane
+    header="src/app/flying-heroes.pipe.ts (FlyingHeroesPipe)"
+    region="pure"
+    path="pipes/src/app/flying-heroes.pipe.ts">
   </code-pane>
-
 </code-tabs>
 
-
-
-You inherit from `FlyingHeroesPipe` to prove the point that nothing changed internally.
-The only difference is the `pure` flag in the pipe metadata.
-
-This is a good candidate for an impure pipe because the `transform` function is trivial and fast.
-
+`FlyingHeroesImpurePipe` is a good candidate for an impure pipe because the `transform` function is trivial and fast:
 
 <code-example path="pipes/src/app/flying-heroes.pipe.ts" header="src/app/flying-heroes.pipe.ts (filter)" region="filter"></code-example>
 
-
-
 You can derive a `FlyingHeroesImpureComponent` from `FlyingHeroesComponent`.
-
+As shown in the code below, only the pipe in the template changes.
 
 <code-example path="pipes/src/app/flying-heroes-impure.component.html" header="src/app/flying-heroes-impure.component.html (excerpt)" region="template-flying-heroes"></code-example>
 
+<div class="alert is-helpful">
 
+  To confirm that the display updates as the user adds heroes, see the <live-example></live-example>.
 
-The only substantive change is the pipe in the template.
-You can confirm in the <live-example></live-example> that the _flying heroes_
-display updates as you add heroes, even when you mutate the `heroes` array.
-
+</div>
 
 {@a async-pipe}
-<h3 class="no-toc">The impure <i>AsyncPipe</i></h3>
 
+## Unwrapping data from an observable
 
-The Angular `AsyncPipe` is an interesting example of an impure pipe.
-The `AsyncPipe` accepts a `Promise` or `Observable` as input
-and subscribes to the input automatically, eventually returning the emitted values.
+[Observables](/guide/glossary#observable "Definition of observable") let you pass messages between parts of your application.
+Observables are recommended for event handling, asynchronous programming, and handling multiple values.
+Observables can deliver single or multiple values of any type, either synchronously (as a function delivers a value to its caller) or asynchronously on a schedule. 
 
-The `AsyncPipe` is also stateful.
-The pipe maintains a subscription to the input `Observable` and
-keeps delivering values from that `Observable` as they arrive.
+<div class="alert is-helpful">
 
-This next example binds an `Observable` of message strings
+For details and examples of observables, see the [Observables Overview](/guide/observables#using-observables-to-pass-values "Using observables to pass values"").
+
+</div>
+
+Use the built-in [`AsyncPipe`](/api/common/AsyncPipe "API description of AsyncPipe") to accept an observable as input and subscribe to the input automatically.
+Without this pipe, your component code would have to subscribe to the observable to consume its values, extract the resolved values, expose them for binding, and unsubscribe when the observable is destroyed in order to prevent memory leaks. `AsyncPipe` is an impure pipe that saves boilerplate code in your component to maintain the subscription and keep delivering values from that observable as they arrive.
+
+The following code example binds an observable of message strings
 (`message$`) to a view with the `async` pipe.
 
-
 <code-example path="pipes/src/app/hero-async-message.component.ts" header="src/app/hero-async-message.component.ts">
 
 </code-example>
 
+{@a no-filter-pipe}
 
+## Caching HTTP requests
 
-The Async pipe saves boilerplate in the component code.
-The component doesn't have to subscribe to the async data source,
-extract the resolved values and expose them for binding,
-and have to unsubscribe when it's destroyed
-(a potent source of memory leaks).
+To [communicate with backend services using HTTP](/guide/http "Communicating with backend services using HTTP"), the `HttpClient` service uses observables and offers the `HTTPClient.get()` method to fetch data from a server.
+The aynchronous method sends an HTTP request, and returns an observable that emits the requested data for the response.
 
-<h3 class="no-toc">An impure caching pipe</h3>
+As shown in the previous section, you can use the impure `AsyncPipe` to accept an observable as input and subscribe to the input automatically.
+You can also create an impure pipe to make and cache an HTTP request.
 
-Write one more impure pipe, a pipe that makes an HTTP request.
+Impure pipes are called whenever change detection runs for a component, which could be every few milliseconds for `CheckAlways`.
+To avoid performance problems, call the server only when the requested URL changes, as shown in the following example, and use the pipe to cache the server response.
+The tabs show the following:
 
-Remember that impure pipes are called every few milliseconds.
-If you're not careful, this pipe will punish the server with requests.
+* The `fetch` pipe (`fetch-json.pipe.ts`).
+* A harness component (`hero-list.component.ts`) for demonstrating the request, using a template that defines two bindings to the pipe requesting the heroes from the `heroes.json` file. The second binding chains the `fetch` pipe with the built-in `JsonPipe` to display the same hero data in JSON format.
 
-In the following code, the pipe only calls the server when the requested URL changes and it caches the server response.
-The code uses the [Angular http](guide/http) client to retrieve data:
+<code-tabs>
+  <code-pane
+    header="src/app/fetch-json.pipe.ts"
+    path="pipes/src/app/fetch-json.pipe.ts">
+  </code-pane>
+  <code-pane
+    header="src/app/hero-list.component.ts"
+    path="pipes/src/app/hero-list.component.ts">
+  </code-pane>
+</code-tabs>
 
+In the above example, a breakpoint on the pipe's request for data shows the following:
 
-<code-example path="pipes/src/app/fetch-json.pipe.ts" header="src/app/fetch-json.pipe.ts">
-
-</code-example>
-
-
-
-Now demonstrate it in a harness component whose template defines two bindings to this pipe,
-both requesting the heroes from the `heroes.json` file.
-
-
-<code-example path="pipes/src/app/hero-list.component.ts" header="src/app/hero-list.component.ts">
-
-</code-example>
-
-
-
-The component renders as the following:
+* Each binding gets its own pipe instance.
+* Each pipe instance caches its own URL and data and calls the server only once.
 
+The `fetch` and `fetch-json` pipes display the heroes as shown in Figure 5.
 
 <div class="lightbox">
   <img src='generated/images/guide/pipes/hero-list.png' alt="Hero List">
 </div>
 
+**Figure 5.** The `fetch` and `fetch-json` pipes displaying the heroes
 
+<div class="alert is-helpful">
 
-A breakpoint on the pipe's request for data shows the following:
-
-* Each binding gets its own pipe instance.
-* Each pipe instance caches its own URL and data.
-* Each pipe instance only calls the server once.
-
-<h3 class="no-toc"><i>JsonPipe</i></h3>
-
-In the previous code sample, the second `fetch` pipe binding demonstrates more pipe chaining.
-It displays the same hero data in JSON format by chaining through to the built-in `JsonPipe`.
-
-
-<div class="callout is-helpful">
-
-
-
-<header>
-  Debugging with the json pipe
-</header>
-
-
-
-The [JsonPipe](api/common/JsonPipe)
-provides an easy way to diagnose a mysteriously failing data binding or
-inspect an object for future binding.
-
+The built-in [JsonPipe](api/common/JsonPipe "API description for JsonPipe") provides a way to diagnose a mysteriously failing data binding or to inspect an object for future binding.
 
 </div>
-
-
-
-{@a pure-pipe-pure-fn}
-
-
-<h3 class="no-toc">Pure pipes and pure functions</h3>
-
-A pure pipe uses pure functions.
-Pure functions process inputs and return values without detectable side effects.
-Given the same input, they should always return the same output.
-
-The pipes discussed earlier in this page are implemented with pure functions.
-The built-in `DatePipe` is a pure pipe with a pure function implementation.
-So are the `ExponentialStrengthPipe` and `FlyingHeroesPipe`.
-A few steps back, you reviewed the `FlyingHeroesImpurePipe`&mdash;an impure pipe with a pure function.
-
-But always implement a *pure pipe* with a *pure function*.
-Otherwise, you'll see many console errors regarding expressions that changed after they were checked.
-
-
-
-## Next steps
-
-Pipes are a great way to encapsulate and share common display-value
-transformations. Use them like styles, dropping them
-into your template's expressions to enrich the appeal and usability
-of your views.
-
-Explore Angular's inventory of built-in pipes in the [API Reference](api?type=pipe).
-Try writing a custom pipe and perhaps contributing it to the community.
-
-
-{@a no-filter-pipe}
-
-
-
-## Appendix: No *FilterPipe* or *OrderByPipe*
-
-Angular doesn't provide pipes for filtering or sorting lists.
-Developers familiar with AngularJS know these as `filter` and `orderBy`.
-There are no equivalents in Angular.
-
-This isn't an oversight. Angular doesn't offer such pipes because
-they perform poorly and prevent aggressive minification.
-Both `filter` and `orderBy` require parameters that reference object properties.
-Earlier in this page, you learned that such pipes must be [impure](guide/pipes#pure-and-impure-pipes) and that
-Angular calls impure pipes in almost every change-detection cycle.
-
-Filtering and especially sorting are expensive operations.
-The user experience can degrade severely for even moderate-sized lists when Angular calls these pipe methods many times per second.
-`filter` and `orderBy` have often been abused in AngularJS apps, leading to complaints that Angular itself is slow.
-That charge is fair in the indirect sense that AngularJS prepared this performance trap
-by offering `filter` and `orderBy` in the first place.
-
-The minification hazard is also compelling, if less obvious. Imagine a sorting pipe applied to a list of heroes.
-The list might be sorted by hero `name` and `planet` of origin properties in the following way:
-
-<code-example language="html">
-  &lt;!-- NOT REAL CODE! -->
-  &lt;div *ngFor="let hero of heroes | orderBy:'name,planet'">&lt;/div>
-</code-example>
-
-
-
-You identify the sort fields by text strings, expecting the pipe to reference a property value by indexing
-(such as `hero['name']`).
-Unfortunately, aggressive minification manipulates the `Hero` property names so that `Hero.name` and `Hero.planet`
-become something like `Hero.a` and `Hero.b`. Clearly `hero['name']` doesn't work.
-
-While some may not care to minify this aggressively,
-the Angular product shouldn't prevent anyone from minifying aggressively.
-Therefore, the Angular team decided that everything Angular provides will minify safely.
-
-The Angular team and many experienced Angular developers strongly recommend moving
-filtering and sorting logic into the component itself.
-The component can expose a `filteredHeroes` or `sortedHeroes` property and take control
-over when and how often to execute the supporting logic.
-Any capabilities that you would have put in a pipe and shared across the app can be
-written in a filtering/sorting service and injected into the component.
-
-If these performance and minification considerations don't apply to you, you can always create your own such pipes
-(similar to the [FlyingHeroesPipe](guide/pipes#impure-flying-heroes)) or find them in the community.

aio/content/guide/releases.md

@@ -101,6 +101,7 @@ The following table provides the status for Angular versions under support.
 
 Version | Status | Released     | Active Ends  | LTS Ends
 ------- | ------ | ------------ | ------------ | ------------
+^10.0.0 | Active | Jun 24, 2020 | Dec 24, 2020 | Dec 24, 2021
 ^9.0.0  | Active | Feb 06, 2020 | Aug 06, 2020 | Aug 06, 2021
 ^8.0.0  | LTS    | May 28, 2019 | Nov 28, 2019 | Nov 28, 2020
 

aio/content/guide/schematics-for-libraries.md

@@ -1,7 +1,7 @@
 # Schematics for libraries
 
 When you create an Angular library, you can provide and package it with schematics that integrate it with the Angular CLI.
-With your schematics, your users can use  `ng add` to install an initial version of your library,
+With your schematics, your users can use `ng add` to install an initial version of your library,
 `ng generate` to create artifacts defined in your library, and `ng update` to adjust their project for a new version of your library that introduces breaking changes.
 
 All three types of schematics can be part of a collection that you package with your library.
@@ -115,10 +115,10 @@ When you add a schematic to the collection, you have to point to it in the colle
 <code-example header="projects/my-lib/schematics/my-service/schema.json (Schematic JSON Schema)" path="schematics-for-libraries/projects/my-lib/schematics/my-service/schema.json">
 </code-example>
 
-  * *id* : A unique id for the schema in the collection.
-  * *title* : A human-readable description of the schema.
-  * *type* : A descriptor for the type provided by the properties.
-  * *properties* : An object that defines the available options for the schematic.
+  * *id*: A unique id for the schema in the collection.
+  * *title*: A human-readable description of the schema.
+  * *type*: A descriptor for the type provided by the properties.
+  * *properties*: An object that defines the available options for the schematic.
 
   Each option associates key with a type, description, and optional alias.
   The type defines the shape of the value you expect, and the description is displayed when the user requests usage help for your schematic.
@@ -130,9 +130,9 @@ When you add a schematic to the collection, you have to point to it in the colle
 <code-example header="projects/my-lib/schematics/my-service/schema.ts (Schematic Interface)" path="schematics-for-libraries/projects/my-lib/schematics/my-service/schema.ts">
 </code-example>
 
-  * *name* : The name you want to provide for the created service.
-  * *path* : Overrides the path provided to the schematic. The default path value is based on the current working directory.
-  * *project* : Provides a specific project to run the schematic on. In the schematic, you can provide a default if the option is not provided by the user.
+  * *name*: The name you want to provide for the created service.
+  * *path*: Overrides the path provided to the schematic. The default path value is based on the current working directory.
+  * *project*: Provides a specific project to run the schematic on. In the schematic, you can provide a default if the option is not provided by the user.
 
 ### Add template files
 
@@ -169,10 +169,9 @@ The Schematics framework provides a file templating system, which supports both
 The system operates on placeholders defined inside files or paths that loaded in the input `Tree`.
 It fills these in using values passed into the `Rule`.
 
-For details of these data structure and syntax, see the [Schematics README](https://github.com/angular/angular-cli/blob/master/packages/angular_devkit/schematics/README.md).
+For details of these data structures and syntax, see the [Schematics README](https://github.com/angular/angular-cli/blob/master/packages/angular_devkit/schematics/README.md).
 
-
-1. Create the main file, `index.ts` and add the source code for your schematic factory function.
+1. Create the main file `index.ts` and add the source code for your schematic factory function.
 
 1. First, import the schematics definitions you will need. The Schematics framework offers many utility functions to create and use rules when running a schematic.
 
@@ -271,7 +270,6 @@ For more information about rules and utility methods, see [Provided Rules](https
 
 After you build your library and schematics, you can install the schematics collection to run against your project. The steps below show you how to generate a service using the schematic you created above.
 
-
 ### Build your library and schematics
 
 From the root of your workspace, run the `ng build` command for your library.

aio/content/guide/service-worker-communications.md

@@ -31,28 +31,27 @@ You can use these events to notify the user of a pending update or to refresh th
 
 ### Checking for updates
 
-It's possible to ask the service worker to check if any updates have been deployed to the server. You might choose to do this if you have a site that changes frequently or want updates to happen on a schedule.
+It's possible to ask the service worker to check if any updates have been deployed to the server.
+The service worker checks for updates during initialization and on each navigation request—that is, when the user navigates from a different address to your app.
+However, you might choose to manually check for updates if you have a site that changes frequently or want updates to happen on a schedule.
 
 Do this with the `checkForUpdate()` method:
 
 <code-example path="service-worker-getting-started/src/app/check-for-update.service.ts" header="check-for-update.service.ts"></code-example>
 
-
 This method returns a `Promise` which indicates that the update check has completed successfully, though it does not indicate whether an update was discovered as a result of the check. Even if one is found, the service worker must still successfully download the changed files, which can fail. If successful, the `available` event will indicate availability of a new version of the app.
 
 <div class="alert is-important">
 
-In order to avoid negatively affecting the initial rendering, `ServiceWorkerModule` will by default
-wait for the app to stabilize, before registering the ServiceWorker script. Constantly polling for
-updates, e.g. with `interval()`, will prevent the app from stabilizing and the ServiceWorker
-script will never be registered with the browser.
-
-You can avoid that by waiting for the app to stabilize first, before starting to poll for updates
-(as shown in the example above).
+In order to avoid negatively affecting the initial rendering of the page, `ServiceWorkerModule` waits for up to 30 seconds by default for the app to stabilize, before registering the ServiceWorker script.
+Constantly polling for updates, for example, with [setInterval()](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setInterval) or RxJS' [interval()](https://rxjs.dev/api/index/function/interval), will prevent the app from stabilizing and the ServiceWorker script will not be registered with the browser until the 30 seconds upper limit is reached.
 
 Note that this is true for any kind of polling done by your application.
 Check the {@link ApplicationRef#isStable isStable} documentation for more information.
 
+You can avoid that delay by waiting for the app to stabilize first, before starting to poll for updates, as shown in the example above.
+Alternatively, you might want to define a different {@link SwRegistrationOptions#registrationStrategy registration strategy} for the ServiceWorker.
+
 </div>
 
 ### Forcing update activation
@@ -61,7 +60,12 @@ If the current tab needs to be updated to the latest app version immediately, it
 
 <code-example path="service-worker-getting-started/src/app/prompt-update.service.ts" header="prompt-update.service.ts" region="sw-activate"></code-example>
 
-Doing this could break lazy-loading in currently running apps, especially if the lazy-loaded chunks use filenames with hashes, which change every version.
+<div class="alert is-important">
+
+Calling `activateUpdate()` without reloading the page could break lazy-loading in a currently running app, especially if the lazy-loaded chunks use filenames with hashes, which change every version.
+Therefore, it is recommended to reload the page once the promise returned by `activateUpdate()` is resolved.
+
+</div>
 
 ## More on Angular service workers
 

aio/content/guide/service-worker-config.md

@@ -193,6 +193,21 @@ The Angular service worker can use either of two caching strategies for data res
 
 * `freshness` optimizes for currency of data, preferentially fetching requested data from the network. Only if the network times out, according to `timeout`, does the request fall back to the cache. This is useful for resources that change frequently; for example, account balances.
 
+
+<div class="alert is-helpful">
+
+You can also emulate a third strategy, [staleWhileRevalidate](https://developers.google.com/web/fundamentals/instant-and-offline/offline-cookbook/#stale-while-revalidate), which returns cached data (if available), but also fetches fresh data from the network in the background for next time.
+To use this strategy set `strategy` to `freshness` and `timeout` to `0u` in `cacheConfig`.
+
+This will essentially do the following:
+
+1. Try to fetch from the network first.
+2. If the network request does not complete after 0ms (i.e. immediately), fall back to the cache (ignoring cache age).
+3. Once the network request completes, update the cache for future requests.
+4. If the resource does not exist in the cache, wait for the network request anyway.
+
+</div>
+
 ### `cacheQueryOptions`
 
 See [assetGroups](#assetgroups) for details.

aio/content/guide/service-worker-getting-started.md

@@ -107,7 +107,7 @@ Notice that all of the files the browser needs to render this application are ca
 <div class="alert is-helpful">
 Pay attention to two key points:
 
-1. The generated `ngsw-config.json` includes a limited list of cachable fonts and images extentions. In some cases, you might want to modify the glob pattern to suit your needs.
+1. The generated `ngsw-config.json` includes a limited list of cacheable fonts and images extentions. In some cases, you might want to modify the glob pattern to suit your needs.
 
 1. If `resourcesOutputPath` or `assets` paths are modified after the generation of configuration file, you need to change the paths manually in `ngsw-config.json`.
 </div>

aio/content/guide/setup-local.md

@@ -25,49 +25,48 @@ To use the Angular framework, you should be familiar with the following:
 
 Knowledge of [TypeScript](https://www.typescriptlang.org/) is helpful, but not required.
 
+To install Angular on your local system, you need the following:
+
 {@a nodejs}
-### Node.js
 
-Make sure your development environment includes `Node.js®` and an npm package manager.
+* **Node.js**
+  
+  Angular requires a [current, active LTS, or maintenance LTS](https://nodejs.org/about/releases) version of Node.js.
 
-Angular requires a [current, active LTS, or maintenance LTS](https://nodejs.org/about/releases/) version of `Node.js`. See the `engines` key for the specific version requirements in our [package.json](https://unpkg.com/@angular/cli/package.json).
+  <div class="alert is-helpful">
 
-* To check your version, run `node -v` in a terminal/console window.
+  For information about specific version requirements, see the `engines` key in the [package.json](https://unpkg.com/@angular/cli/package.json) file.
 
-* To get `Node.js`, go to [nodejs.org](https://nodejs.org "Nodejs.org").
+  </div>
+
+  For more information on installing Node.js, see [nodejs.org](http://nodejs.org "Nodejs.org").
+  If you are unsure what version of Node.js runs on your system, run `node -v` in a terminal window.
 
 {@a npm}
-### npm package manager
 
-Angular, the Angular CLI, and Angular apps depend on features and functionality provided by libraries that are available as [npm packages](https://docs.npmjs.com/getting-started/what-is-npm). To download and install npm packages, you must have an npm package manager.
+* **npm package manager**
 
-This setup guide uses the [npm client](https://docs.npmjs.com/cli/install) command line interface, which is installed with `Node.js` by default.
-
-To check that you have the npm client installed, run `npm -v` in a terminal/console window.
+  Angular, the Angular CLI, and Angular applications depend on [npm packages](https://docs.npmjs.com/getting-started/what-is-npm) for many features and functions.
+  To download and install npm packages, you need an npm package manager.
+  This guide uses the [npm client](https://docs.npmjs.com/cli/install) command line interface, which is installed with `Node.js` by default.
+  To check that you have the npm client installed, run `npm -v` in a terminal window.
 
 
 {@a install-cli}
 
-## Step 1: Install the Angular CLI
+## Install the Angular CLI
 
-You use the Angular CLI
-to create projects, generate application and library code, and perform a variety of ongoing development tasks such as testing, bundling, and deployment.
-
-Install the Angular CLI globally.
-
-To install the CLI using `npm`, open a terminal/console window and enter the following command:
+You use the Angular CLI to create projects, generate application and library code, and perform a variety of ongoing development tasks such as testing, bundling, and deployment.
 
+To install the Angular CLI, open a terminal window and run the following command:
 
 <code-example language="sh" class="code-shell">
   npm install -g @angular/cli
-
 </code-example>
 
-
-
 {@a create-proj}
 
-## Step 2: Create a workspace and initial application
+## Create a workspace and initial application
 
 You develop apps in the context of an Angular [**workspace**](guide/glossary#workspace).
 
@@ -86,16 +85,22 @@ The Angular CLI installs the necessary Angular npm packages and other dependenci
 
 The CLI creates a new workspace and a simple Welcome app, ready to run.
 
+<div class="alert is-helpful">
+
+You also have the option to use Angular's strict mode, which can help you write better, more maintainable code.
+For more information, see [Strict mode](/guide/strict-mode).
+
+</div>
 
 {@a serve}
 
-## Step 3: Run the application
+## Run the application
 
-The Angular CLI includes a server, so that you can easily build and serve your app locally.
+The Angular CLI includes a server, so that you can build and serve your app locally.
 
-1. Go to the workspace folder (`my-app`).
+1. Navigate to the workspace folder, such as `my-app`.
 
-1. Launch the server by using the CLI command `ng serve`, with the `--open` option.
+1. Run the following command:
 
 <code-example language="sh" class="code-shell">
   cd my-app
@@ -108,7 +113,7 @@ and rebuilds the app as you make changes to those files.
 The `--open` (or just `-o`) option automatically opens your browser
 to `http://localhost:4200/`.
 
-You will see:
+If your installation and setup was successful, you should see a page similar to the following.
 
 
 <div class="lightbox">

aio/content/guide/strict-mode.md

@@ -0,0 +1,46 @@
+# Strict mode
+
+When you create a new workspace or a project you have an option to create them in a strict mode using the `--strict` flag.
+
+Enabling this flag initializes your new workspace or project with a few new settings that improve maintainability, help you catch bugs ahead of time, and allow the CLI to perform advanced optimizations on your application.
+Additionally, applications that use these stricter settings are easier to statically analyze, which can help the `ng update` command refactor code more safely and precisely when you are updating to future versions of Angular.
+
+Specifically, the `strict` flag does the following:
+
+* Enables [`strict` mode in TypeScript](https://www.staging-typescript.org/tsconfig#strict), as well as other strictness flags recommended by the TypeScript team. Specifically, `forceConsistentCasingInFileNames`, `noImplicitReturns`,  `noFallthroughCasesInSwitch`.
+* Turns on strict Angular compiler flags [`strictTemplates`](guide/angular-compiler-options#stricttemplates) and [`strictInjectionParameters`](guide/angular-compiler-options#strictinjectionparameters)
+* [Bundle size budgets](guide/build#configuring-size-budgets) have been reduced by ~75%
+* Turns on [`no-any` tslint rule](https://palantir.github.io/tslint/rules/no-any/) to prevent declarations of type `any`
+* [Marks your application as side-effect free](https://webpack.js.org/guides/tree-shaking/#mark-the-file-as-side-effect-free) to enable more advanced tree-shaking
+
+You can apply these settings at the workspace and project level.
+
+To create a new workspace and application using the strict mode, run the following command:
+
+<code-example language="sh" class="code-shell">
+
+ng new [project-name] --strict
+
+</code-example>
+
+To create a new application in the strict mode within an existing non-strict workspace, run the following command:
+
+<code-example language="sh" class="code-shell">
+
+ng generate application [project-name] --strict
+
+</code-example>
+
+{@a side-effect}
+
+### Non-local side effects in applications
+
+When you create projects and workspaces using the `strict` mode, you'll notice an additional `package.json` file, located in `src/app/` directory.
+This file informs tools and bundlers that the code under this directory is free of non-local side effects. Non-local side effects in the application code are not common and using them is not considered a good coding pattern.
+More importantly, code with these types of side effects cannot be optimized, resulting in increased bundle sizes and applications that load more slowly.
+
+If you need more information, the following links may be helpful.
+
+* [Tree-shaking](https://webpack.js.org/guides/tree-shaking/)
+* [Dealing with side effects and pure functions in JavaScript](https://dev.to/vonheikemen/dealing-with-side-effects-and-pure-functions-in-javascript-16mg)
+* [How to deal with dirty side effects in your pure function JavaScript](https://jrsinclair.com/articles/2018/how-to-deal-with-dirty-side-effects-in-your-pure-functional-javascript/)

aio/content/guide/structural-directives.md

@@ -251,7 +251,7 @@ You enable these features in the string assigned to `ngFor`, which you write in
 
 Everything _outside_ the `ngFor` string stays with the host element
 (the `<div>`) as it moves inside the `<ng-template>`.
-In this example, the `[ngClass]="odd"` stays on the `<div>`.
+In this example, the `[class.odd]="odd"` stays on the `<div>`.
 
 
 </div>

aio/content/guide/template-syntax.md

@@ -821,8 +821,8 @@ content harmlessly. The following is the browser output
 of the `evilTitle` examples.
 
 <code-example language="bash">
-"Template <script>alert("evil never sleeps")</script> Syntax" is the interpolated evil title.
-"Template alert("evil never sleeps")Syntax" is the property bound evil title.
+"Template &lt;script&gt;alert("evil never sleeps")&lt;/script&gt; Syntax" is the interpolated evil title.
+"Template Syntax" is the property bound evil title.
 </code-example>
 
 <hr/>

aio/content/guide/template-typecheck.md

@@ -3,7 +3,7 @@
 ## Overview of template type checking
 
 Just as TypeScript catches type errors in your code, Angular checks the expressions and bindings within the templates of your application and can report any type errors it finds.
-Angular currently has three modes of doing this, depending on the value of the `fullTemplateTypeCheck` and `strictTemplates` flags in the [TypeScript configuration file](guide/typescript-configuration), `tsconfig.json`.
+Angular currently has three modes of doing this, depending on the value of the `fullTemplateTypeCheck` and `strictTemplates` flags in the [TypeScript configuration file](guide/typescript-configuration).
 
 ### Basic mode
 
@@ -107,7 +107,7 @@ There can also be false positives when the typings of an Angular library are eit
 In case of a false positive like these, there are a few options:
 
 * Use the [`$any()` type-cast function](guide/template-syntax#any-type-cast-function) in certain contexts to opt out of type-checking for a part of the expression.
-* You can disable strict checks entirely by setting `strictTemplates: false` in the application's TypeScript configuration file, `tsconfig.json`.
+* You can disable strict checks entirely by setting `strictTemplates: false` in the application's TypeScript configuration file.
 * You can disable certain type-checking operations individually, while maintaining strictness in other aspects, by setting a _strictness flag_ to `false`.
 * If you want to use `strictTemplates` and `strictNullChecks` together, you can opt out of strict null type checking specifically for input bindings via `strictNullInputTypes`.
 

aio/content/guide/testing.md

@@ -93,7 +93,7 @@ Adopt these two conventions in your own projects for _every kind_ of test file.
 
 ## Set up continuous integration
 
-One of the best ways to keep your project bug free is through a test suite, but it's easy to forget to run tests all the time.
+One of the best ways to keep your project bug-free is through a test suite, but it's easy to forget to run tests all the time.
 Continuous integration (CI) servers let you set up your project repository so that your tests run on every commit and pull request.
 
 There are paid CI services like Circle CI and Travis CI, and you can also host your own for free using Jenkins and others.

aio/content/guide/typescript-configuration.md

@@ -15,22 +15,49 @@ that are important to Angular developers, including details about the following
 
 {@a tsconfig}
 
-## TypeScript configuration
+## Configuration files
 
-A TypeScript configuration file called `tsconfig.json` guides the compiler as it generates JavaScript files for a project.
-This file contains options and flags that are essential for Angular applications.
-Typically, the file is found at the [root level of the workspace](guide/file-structure).
+A given Angular workspace contains several TypeScript configuration files.
+At the root level, there are two main TypeScript configuration files: a `tsconfig.json` file and a `tsconfig.base.json` file.
+
+The `tsconfig.json` file is a ["Solution Style"](https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-9.html#support-for-solution-style-tsconfigjson-files) TypeScript configuration file.
+Code editors and TypeScript’s language server use this file to improve development experience.
+Compilers do not use this file.
+
+The `tsconfig.json` file contains a list of paths to the other TypeScript configuration files used in the workspace.
+
+<code-example lang="json" header="tsconfig.json" linenums="false">
+{
+ "files": [],
+ "references": [
+   {
+     "path": "./tsconfig.app.json"
+   },
+   {
+     "path": "./tsconfig.spec.json"
+   },
+   {
+     "path": "./projects/my-lib/tsconfig.lib.json"
+   }
+ ]
+}
+</code-example>
+
+The `tsconfig.base.json` file specifies the base TypeScript and Angular compiler options that all projects in the workspace inherit.
+
+The TypeScript and Angular have a wide range of options which can be used to configure type-checking features and generated output.
+For more information, see the [Configuration inheritance with extends](https://www.typescriptlang.org/docs/handbook/tsconfig-json.html#configuration-inheritance-with-extends) section of the TypeScript documentation.
 
 <div class="alert is-helpful">
 
-For details about `tsconfig.json`, see the official
-[TypeScript wiki](http://www.typescriptlang.org/docs/handbook/tsconfig-json.html).
+For more information TypeScript configuration files, see the official [TypeScript wiki](http://www.typescriptlang.org/docs/handbook/tsconfig-json.html)
+For details about configuration inheritance, see the [Configuration inheritance with extends](https://www.typescriptlang.org/docs/handbook/tsconfig-json.html#configuration-inheritance-with-extends) section.
 
 </div>
 
-The initial `tsconfig.json` for an Angular app typically looks like the following example.
+The initial `tsconfig.base.json` for an Angular workspace typically looks like the following example.
 
-<code-example lang="json" header="tsconfig.json" linenums="false">
+<code-example lang="json" header="tsconfig.base.json" linenums="false">
 {
   "compileOnSave": false,
   "compilerOptions": {
@@ -40,25 +67,22 @@ The initial `tsconfig.json` for an Angular app typically looks like the followin
     "declaration": false,
     "downlevelIteration": true,
     "experimentalDecorators": true,
-    "module": "esnext",
     "moduleResolution": "node",
     "importHelpers": true,
     "target": "es2015",
-    "typeRoots": [
-      "node_modules/@types"
-    ],
+    "module": "es2020",
     "lib": [
       "es2018",
       "dom"
     ]
-  },
-  "angularCompilerOptions": {
-    "strictTemplates": true,
-    "strictInjectionParameters": true
   }
 }
 </code-example>
 
+### Strict mode
+
+When you create new workspaces and projects, you have the option to use Angular's strict mode, which can help you write better, more maintainable code.
+For more information, see [Strict mode](/guide/strict-mode).
 
 {@a noImplicitAny}
 

aio/content/guide/universal.md

@@ -48,11 +48,11 @@ src/
   app/ ...                   <i>application code</i>
     app.server.module.ts     <i>* server-side application module</i>
 server.ts                    <i>* express web server</i>
-tsconfig.json                <i>TypeScript client configuration</i>
-tsconfig.app.json            <i>TypeScript client configuration</i>
-tsconfig.server.json         <i>* TypeScript server configuration</i>
-tsconfig.spec.json           <i>TypeScript spec configuration</i>
-package.json                 <i>npm configuration</i>
+tsconfig.json                <i>TypeScript solution style configuration</i>
+tsconfig.base.json           <i>TypeScript base configuration</i>
+tsconfig.app.json            <i>TypeScript browser application configuration</i>
+tsconfig.server.json         <i>TypeScript server application configuration</i>
+tsconfig.spec.json           <i>TypeScript tests configuration</i>
 </code-example>
 
 The files marked with `*` are new and not in the original tutorial sample.

aio/content/guide/updating-to-version-10.md

@@ -0,0 +1,82 @@
+# Updating to Angular version 10
+
+This guide contains information related to updating to version 10 of Angular.
+
+<div class="alert is-helpful">
+
+For information on upgrading to Angular version 9, see [Updating to Angular version 9](https://v9.angular.io/guide/updating-to-version-9).
+
+</div>
+
+## Updating CLI Apps
+
+For step-by-step instructions on how to update to the latest Angular release (and leverage our automated migration tools to do so), use the interactive update guide at [update.angular.io](https://update.angular.io).
+
+If you're curious about the specific migrations being run by the CLI, see the [automated migrations section](#migrations) for details on what code is changing and why.
+
+## Changes and Deprecations in Version 10
+
+<div class="alert is-helpful">
+
+   For information about Angular's deprecation and removal practices, see [Angular Release Practices](guide/releases#deprecation-practices "Angular Release Practices: Deprecation practices").
+
+</div>
+
+{@a breaking-changes}
+### New Breaking Changes
+
+* Typescript 3.6, 3.7, and 3.8 are no longer supported. Please update to Typescript 3.9.
+* Input fields of type `number` fire the `valueChanges` event only once per value change (as opposed to twice in some cases). See [PR 36087](https://github.com/angular/angular/pull/36087).
+* The `minLength` and `maxLength` validators only validate values that have a numeric `length` property. See [PR 36157](https://github.com/angular/angular/pull/36157).
+* Templates with unknown property bindings or unknown element names now log errors instead of warnings. See [PR 36399](https://github.com/angular/angular/pull/36399).
+* `UrlMatcher` can now return `null` values. See [PR 36402](https://github.com/angular/angular/pull/36402).
+* Transplanted views now refresh at insertion point only. See PR 35968](https://github.com/angular/angular/pull/35968).
+* Formatting times with the `b` or `B` format codes now supports time periods that cross midnight. See [PR 36611](https://github.com/angular/angular/pull/36611).
+* Navigation is canceled for routes with at least one empty resolver. See [PR 24621](https://github.com/angular/angular/pull/24621).
+
+{@a deprecations}
+### New Deprecations
+
+| Area                          | API or Feature                                                                 | May be removed in |
+| ----------------------------- | ---------------------------------------------------------------------------    | ----------------- |
+| `@angular/core`               | [`WrappedValue`](guide/deprecations#wrapped-value)                                     | <!--v10--> v12 |
+| browser support               | [`IE 9, 10, and IE Mobile`](guide/deprecations#ie-9-10-and-ie-mobile-support) | <!--v10--> v11 |
+
+
+{@a removals}
+### New Removals of Deprecated APIs
+
+The following APIs have been removed starting with version 10.0.0*:
+
+| Package          | API            | Replacement | Notes |
+| ---------------- | -------------- | ----------- | ----- |
+| `@angular/core`  | Undecorated base classes that use Angular features | Add Angular decorator | See [migration guide](guide/migration-undecorated-classes) for more info |
+| `@angular/core`  | `ModuleWithProviders` without a generic             | `ModuleWithProviders` with a generic | See [migration guide](guide/migration-module-with-providers) for more info |
+| `@angular/core`  | Style Sanitization | no action needed | See [style sanitization API removal](/guide/deprecations#style-sanitization) for more info
+| `@angular/bazel` | [`Bazel builder and schematics`](guide/deprecations#bazelbuilder) | `bazelbuild/rules_nodejs` | [More info](https://github.com/angular/angular/tree/10.0.x/packages/bazel/src/schematics) |
+
+
+*To see APIs removed in version 9, check out this guide on the [version 9 docs site](https://v9.angular.io/guide/deprecations#removed).
+
+{@a ivy}
+
+## Ivy features and compatibility
+
+Since version 9, Angular Ivy is the default rendering engine. If you haven't heard of Ivy, you can read more about it in the [Angular Ivy guide](guide/ivy).
+
+* Among other features, Ivy introduces more comprehensive type-checking within templates. For details, see [Template Type-checking](guide/template-typecheck).
+
+* For general guidance on debugging and a list of minor changes associated with Ivy, see the [Ivy compatibility guide](guide/ivy-compatibility).
+
+* For help with opting out of Ivy, see the instructions [here](guide/ivy#opting-out-of-angular-ivy).
+
+{@a migrations}
+## Automated Migrations for Version 10
+
+Read about the migrations the CLI handles for you automatically:
+
+* [Migrating missing `@Directive()`/`@Component()` decorators](guide/migration-undecorated-classes)
+* [Migrating `ModuleWithProviders`](guide/migration-module-with-providers)
+* [Solution-style `tsconfig.json` migration](guide/migration-solution-style-tsconfig)
+* [`tslib` direct dependency migration](guide/migration-update-libraries-tslib)
+* [Update `module` and `target` compiler options migration](guide/migration-update-module-and-target-compiler-options)

aio/content/guide/updating-to-version-9.md

@@ -1,90 +0,0 @@
-# Updating to Angular version 9
-
-This guide contains information related to updating to version 9 of Angular.
-
-## Updating CLI Apps
-
-For step-by-step instructions on how to update to the latest Angular release (and leverage our automated migration tools to do so), use the interactive update guide at [update.angular.io](https://update.angular.io).
-
-If you're curious about the specific migrations being run by the CLI, see the [automated migrations section](#migrations) for details on what code is changing and why.
-
-## Changes and Deprecations in Version 9
-
-<div class="alert is-helpful">
-
-   For information about Angular's deprecation and removal practices, see [Angular Release Practices](guide/releases#deprecation-practices "Angular Release Practices: Deprecation practices").
-
-</div>
-
-{@a breaking-changes}
-### New Breaking Changes
-
-- Angular now compiles with Ivy by default. See the [Ivy compatibility section](#ivy).
-
-- CLI apps compile in [AOT mode](/guide/aot-compiler) by default (which includes template type-checking).
-Users who only built with JIT before may see new type errors.
-See our [template type-checking guide](guide/template-typecheck) for more information and debugging tips.
-
-- Typescript 3.4 and 3.5 are no longer supported. Please update to Typescript 3.7.
-
-- `tslib` is now listed as a peer dependency rather than a direct dependency. If you are not using the CLI, you must manually install `tslib`, using `yarn add tslib` or `npm install tslib --save`.
-
-{@a deprecations}
-### New Deprecations
-
-| API                                                                     | Replacement                          | Notes |
-| ------------------------------------------------------------------------| ------------------------------------ | ----- |
-| [`entryComponents`](api/core/NgModule#entryComponents)                  | none                                 | See [`entryComponents`](guide/deprecations#entryComponents) |
-| [`CurrencyPipe` - `DEFAULT_CURRENCY_CODE`](api/common/CurrencyPipe#currency-code-deprecation)| `{provide: DEFAULT_CURRENCY_CODE, useValue: 'USD'}` | From v11 the default code will be extracted from the locale data given by `LOCAL_ID`, rather than `USD`. |
-| [`ANALYZE_FOR_ENTRY_COMPONENTS`](api/core/ANALYZE_FOR_ENTRY_COMPONENTS) | none                                 | See [`ANALYZE_FOR_ENTRY_COMPONENTS`](guide/deprecations#entryComponents) |
-| `ModuleWithProviders` without a generic                                 | `ModuleWithProviders` with a generic | |
-| Undecorated base classes that use Angular features                      | Base classes with `@Directive()` decorator that use Angular features |  |
-| `esm5` and `fesm5` distribution in `@angular/*` npm packages            | `esm2015` and `fesm2015` entrypoints | See [`esm5` and `fesm5`](guide/deprecations#esm5-fesm5) |
-| [`TestBed.get`](api/core/testing/TestBed#get)                           | [`TestBed.inject`](api/core/testing/TestBed#inject) | Same behavior, but type safe. |
-
-
-{@a removals}
-### New Removals of Deprecated APIs
-
-| Package | API            | Replacement | Notes |
-| ------- | -------------- | ----------- | ----- |
-| `@angular/core`  | [`Renderer`](https://v8.angular.io/api/core/Renderer) | [`Renderer2`](api/core/Renderer2) | [Migration guide.](guide/migration-renderer) |
-| `@angular/core`  | [`RootRenderer`](https://v8.angular.io/api/core/RootRenderer) | [`RendererFactory2`](api/core/RendererFactory2) | none |
-| `@angular/core`  | [`RenderComponentType`](https://v8.angular.io/api/core/RenderComponentType) | [`RendererType2`](api/core/RendererType2) | none |
-| `@angular/core`  | [`WtfScopeFn`](https://v8.angular.io/api/core/WtfScopeFn) | none | v8 | See [Web Tracing Framework](#wtf) |
-| `@angular/core`  | [`wtfCreateScope`](https://v8.angular.io/api/core/wtfCreateScope) | none | v8 | See [Web Tracing Framework](guide/deprecations#wtf) |
-| `@angular/core`  | [`wtfStartTimeRange`](https://v8.angular.io/api/core/wtfStartTimeRange) | none | v8 | See [Web Tracing Framework](guide/deprecations#wtf) |
-| `@angular/core`  | [`wtfEndTimeRange`](https://v8.angular.io/api/core/wtfEndTimeRange) | none | v8 | See [Web Tracing Framework](guide/deprecations#wtf) |
-| `@angular/core`  | [`wtfLeave`](https://v8.angular.io/api/core/wtfLeave) | none | v8 | See [Web Tracing Framework](guide/deprecations#wtf) |
-| `@angular/common` | `DeprecatedI18NPipesModule` | [`CommonModule`](api/common/CommonModule#pipes) | none |
-| `@angular/common` | `DeprecatedCurrencyPipe` | [`CurrencyPipe`](api/common/CurrencyPipe) | none |
-| `@angular/common` | `DeprecatedDatePipe`     | [`DatePipe`](api/common/DatePipe) | none |
-| `@angular/common` | `DeprecatedDecimalPipe` | [`DecimalPipe`](api/common/DecimalPipe) | none |
-| `@angular/common` | `DeprecatedPercentPipe` | [`PercentPipe`](api/common/PercentPipe) | none |
-| `@angular/forms` | [`NgFormSelectorWarning`](https://v8.angular.io/api/forms/NgFormSelectorWarning) | none |
-| `@angular/forms` | `ngForm` element selector | `ng-form` element selector | none |
-| `@angular/service-worker` | `versionedFiles` | `files` | In the service worker configuration file `ngsw-config.json`, replace `versionedFiles` with `files`. See [Service Worker Configuration](guide/service-worker-config#assetgroups). |
-
-{@a ivy}
-
-## Ivy features and compatibility
-
-In Version 9, Angular Ivy is the default rendering engine. If you haven't heard of Ivy, you can read more about it in the [Angular Ivy guide](guide/ivy).
-
-* Among other features, Ivy introduces more comprehensive type-checking within templates. For details, see [Template Type-checking](guide/template-typecheck).
-
-* For general guidance on debugging and a list of minor changes associated with Ivy, see the [Ivy compatibility guide](guide/ivy-compatibility).
-
-* For help with opting out of Ivy, see the instructions [here](guide/ivy#opting-out-of-angular-ivy).
-
-{@a migrations}
-## Automated Migrations for Version 9
-
-Read about the migrations the CLI handles for you automatically:
-
-- [Migrating from `Renderer` to `Renderer2`](guide/migration-renderer)
-- [Migrating missing `@Directive()`/`@Component()` decorators](guide/migration-undecorated-classes)
-- [Migrating missing `@Injectable()` decorators and incomplete provider definitions](guide/migration-injectable)
-- [Migrating dynamic queries](guide/migration-dynamic-flag)
-- [Migrating to the new `$localize` i18n support](guide/migration-localize)
-- [Migrating `ModuleWithProviders`](guide/migration-module-with-providers)

aio/content/guide/workspace-config.md

@@ -41,6 +41,11 @@ When you create a library project with `ng generate library`, the library projec
 
 </div>
 
+## Strict mode
+
+When you create new workspaces and projects, you have the option to use Angular's strict mode, which can help you write better, more maintainable code.
+For more information, see [Strict mode](/guide/strict-mode).
+
 ## Project configuration options
 
 The following top-level configuration properties are available for each project, under `projects:<project_name>`.

aio/content/marketing/contributors.json

@@ -204,7 +204,7 @@
     "name": "Alyssa Nicoll",
     "picture": "alyssa.jpg",
     "twitter": "alyssanicoll",
-    "website": "alyssa.io",
+    "website": "http://alyssa.io",
     "bio": "Alyssa is an Angular Developer Advocate for KUI and a GDE. Her two degrees (Web Design & Development and Psychology) feed her speaking career. She has spoken at over 35 conferences internationally. She is a weekly panelist on Adventures in Angular and Angular Air, which have a combined following of over 16,000 listeners. She enjoys gaming, scuba diving, and has a newborn that fondly goes by 'Mr. Milks'.",
     "groups": ["GDE"]
   },
@@ -228,7 +228,7 @@
     "name": "Christoffer Noring",
     "picture": "chrisnoring.jpg",
     "twitter": "chris_noring",
-    "website": "softchris.github.io",
+    "website": "https://softchris.github.io",
     "bio": "Chris is a Full Stack Developer at McKinsey. A Google Developer Expert in Web Technologies and Angular. He is also a Nativescript Developer Expert. He is one of the organizers of the Angular conference ngVikings and an author of the book RxJS 5 Ultimate",
     "groups": ["GDE"]
   },
@@ -323,14 +323,6 @@
     "bio": "Sander is a versed developer with over 4 decades of practice under his belt. He is also an Google Developer Expert for web, specializing in Angular. Organizer of meetups and conferences. Helping out others wherever he can. When he is not breathing code, he is fiddling around with IOT, photography, science and anything that might vaguely is gadget-like! Thinks he a master of the grill, but in reality you probably don't get a food-poisoning ;) Also, and actually the most important thing to him, he is a father of 4, and has the most patient girlfriend in the universe.",
     "groups": ["GDE"]
   },
-  "filipbech": {
-    "name": "Filip Bruun Bech-Larsen",
-    "picture": "filipbech.jpg",
-    "twitter": "filipbech",
-    "website": "http://filipbech.github.io/",
-    "bio": "Filip is a Frontend developer from Denmark. He works at IMPACT, delivering large-scale, high-performance e-commerce to international clients - most often build in Angular. He runs the local Angular usergroup - ngAarhus, and gives talks/workshops around and beyond the country of Denmark.",
-    "groups": ["GDE"]
-  },
   "cironunes": {
     "name": "Ciro Nunes",
     "picture": "cironunes.jpg",
@@ -400,14 +392,6 @@
     "bio": "GDE (Google Developer Expert) Angular and Web Technologies, Women Who Code KL Director, Jecelyn specializes in professional application development with technologies, including Angular, HTML5, Typescript, JavaScript, CSS, C#, NodeJs, Cloud and ASP.NET.",
     "groups": ["GDE"]
   },
-  "areai51": {
-    "name": "Vinci Rufus",
-    "picture": "vincirufus.jpg",
-    "twitter": "areai51",
-    "website": "https://developers.google.com/experts/people/vinci-rufus",
-    "bio": "Director of Experience Technology at SapientRazorfish. Consults various brands on their frontend and mobile web architecture. A speaker at various forums and mentor at Launchpad Accelerator and ngGirls India. Spends free time playing with Angular, Preact, web-components  ",
-    "groups": ["GDE"]
-  },
   "tchatel": {
     "name": "Thierry Chatel",
     "picture": "thierrychatel.jpg",
@@ -520,14 +504,6 @@
     "bio": "Brian is a software engineer and GDE in Angular with a passion for learning, writing, speaking, teaching and mentoring. Brian has been building web applications for over 20 years and has long been a fanboy of JavaScript. When not in front of his Macbook Pro Brian is in the Rocky Mountains skiing or hiking.",
     "groups": ["GDE"]
   },
-  "jeffbcross": {
-    "name": "Jeff Cross",
-    "picture": "jeff-cross.jpg",
-    "twitter": "jeffbcross",
-    "website": "https://nrwl.io/",
-    "bio": "Jeff is an Angular Consultant at nrwl.io where he helps enterprise teams succeed with Angular. Prior to founding Nrwl, Jeff was one of the earliest members of the Angular Core Team at Google, and contributed to many of the early state management and performance efforts of AngularJS and Angular.",
-    "groups": ["GDE"]
-  },
   "keilla": {
     "name": "Keilla Menezes Fernandes",
     "picture": "keilla.jpg",
@@ -620,6 +596,13 @@
     "twitter": "devjoost",
     "bio": "Joost is a Software Engineer from the Netherlands with an interest in open source software who likes to learn something new every day. He works at Blueriq during the day and contributes to Angular in his spare time, by working on the Angular compiler and runtime. He may review your PR even if you never asked for it ;)"
   },
+  "sonukapoor": {
+    "name": "Sonu Kapoor",
+    "groups": ["Collaborators"],
+    "picture": "sonukapoor.jpg",
+    "website": "https://www.linkedin.com/in/sonu-kapoor/",
+    "bio": "Sonu is a Software Engineer from Toronto, with a high interest in front-end technologies and algorithms."
+  },
   "jschwarty": {
     "name": "Justin Schwartzenberger",
     "picture": "justinschwartzenberger.jpg",
@@ -831,5 +814,21 @@
     "bio": "Cindy is a Program Manager on the Angular team at Google. She is passionate about improving team processes and overall execution. She enjoys dance fitness, movies and travel.",
     "groups": ["Angular"],
     "lead": "juleskremer"
+  },
+  "wellwind": {
+    "name": "Mike Huang",
+    "picture": "wellwind.jpg",
+    "twitter": "wellwind",
+    "website": "https://wellwind.idv.tw/blog/",
+    "bio": "Mike is a full-stack developer, consultant, blogger, instructor, and conference speaker. He has over 10 years of web development experience and passion to share his knowledge.",
+    "groups": ["GDE"]
+  },
+  "ahasall": {
+    "name": "Amadou Sall",
+    "picture": "ahasall.jpg",
+    "groups": ["GDE"],
+    "twitter": "ahasall",
+    "website": "https://www.amadousall.com",
+    "bio": "Amadou is a Frontend Software Engineer from Senegal based in France. He currently works at Air France where he helps developers build better Angular applications. Passionate about web technologies, Amadou is an international speaker, a technical writer, and a Google Developer Expert in Angular."
   }
 }

aio/content/marketing/events.html

@@ -13,11 +13,6 @@
       </tr>
     </thead>
     <tbody>
-      <tr>
-        <th><a href="https://ngvikings.org/" title="ngVikings">ngVikings</a></th>
-        <td>Oslo, Norway</td>
-        <td>May 25-26 conference, 27 workshops, 2020</td>
-      </tr>
     </tbody>
   </table>
 
@@ -31,6 +26,12 @@
       </tr>
     </thead>
     <tbody>
+      <!-- ng-vikings 2020 -->
+      <tr>
+        <th><a href="https://ngvikings.org/" title="ngVikings">ngVikings</a></th>
+        <td>Oslo, Norway</td>
+        <td>May 25-26 conference, 27 workshops, 2020</td>
+      </tr>
       <!-- ng-conf 2020 -->
       <tr>
         <th><a href="https://ng-conf.org/" title="ng-conf">ng-conf</a></th>

aio/content/navigation.json

@@ -254,11 +254,6 @@
               "title": "Reactive Forms",
               "tooltip": "Create a reactive form using FormBuilder, groups, and arrays."
             },
-            {
-              "url": "guide/forms",
-              "title": "Template-driven Forms",
-              "tooltip": "Create a template-driven form using directives and Angular template syntax."
-            },
             {
               "url": "guide/form-validation",
               "title": "Validate form input",
@@ -511,85 +506,6 @@
           "url": "guide/universal",
           "title": "Server-side Rendering",
           "tooltip": "Render HTML server-side with Angular Universal."
-        },
-        {
-          "title": "Upgrading from AngularJS",
-          "tooltip": "Incrementally upgrade an AngularJS application to Angular.",
-          "children": [
-            {
-              "url": "guide/upgrade-setup",
-              "title": "Setup for Upgrading from AngularJS",
-              "tooltip": "Use code from the Angular QuickStart seed as part of upgrading from AngularJS.",
-              "hidden": true
-            },
-            {
-              "url": "guide/upgrade",
-              "title": "Upgrading Instructions",
-              "tooltip": "Incrementally upgrade an AngularJS application to Angular."
-            },
-            {
-              "url": "guide/upgrade-performance",
-              "title": "Upgrading for Performance",
-              "tooltip": "Upgrade from AngularJS to Angular in a more flexible way."
-            },
-            {
-              "url": "guide/ajs-quick-reference",
-              "title": "AngularJS-Angular Concepts",
-              "tooltip": "Learn how AngularJS concepts and techniques map to Angular."
-            }
-          ]
-        },
-        {
-          "title": "Angular Libraries",
-          "tooltip": "Extending Angular with shared libraries.",
-          "children": [
-            {
-              "url": "guide/libraries",
-              "title": "Libraries Overview",
-              "tooltip": "Understand how and when to use or create libraries."
-            },
-            {
-              "url": "guide/using-libraries",
-              "title": "Using Published Libraries",
-              "tooltip": "Integrate published libraries into an app."
-            },
-            {
-              "url": "guide/creating-libraries",
-              "title": "Creating Libraries",
-              "tooltip": "Extend Angular by creating, publishing, and using your own libraries."
-            }
-          ]
-        },
-        {
-          "title": "Schematics",
-          "tooltip": "Using CLI schematics for code generation.",
-          "children": [
-            {
-              "url": "guide/schematics",
-              "title": "Schematics Overview",
-              "tooltip": "How the CLI uses schematics to generate code."
-            },
-            {
-              "url": "guide/schematics-authoring",
-              "title": "Authoring Schematics",
-              "tooltip": "Understand the structure of a schematic."
-            },
-            {
-              "url": "guide/schematics-for-libraries",
-              "title": "Schematics for Libraries",
-              "tooltip": "Use schematics to integrate your library with the Angular CLI."
-            }
-          ]
-        },
-        {
-          "url": "guide/cli-builder",
-          "title": "CLI Builders",
-          "tooltip": "Using builders to customize Angular CLI."
-        },
-        {
-          "url": "guide/web-worker",
-          "title": "Web Workers in Angular",
-          "tooltip": "Implement background processing with web workers."
         }
       ]
     },
@@ -628,11 +544,6 @@
           "title": "Building & Serving",
           "tooltip": "Building and serving Angular apps."
         },
-        {
-          "url": "guide/bazel",
-          "title": "Building with Bazel",
-          "tooltip": "How to set up your environment to build and test with Bazel."
-        },
         {
           "url": "guide/testing",
           "title": "Testing",
@@ -690,6 +601,11 @@
           "url": "guide/browser-support",
           "title": "Browser Support",
           "tooltip": "Browser support and polyfills guide."
+        },
+        {
+          "url": "guide/strict-mode",
+          "title": "Strict mode",
+          "tooltip": "Reference documentation for Angular's strict mode."
         }
       ]
     },
@@ -754,6 +670,11 @@
           "url": "guide/router-tutorial",
           "title": "Using Angular Routes in a Single-page Application",
           "tooltip": "A tutorial that covers many patterns associated with Angular routing."
+        },
+        {
+          "url": "guide/forms",
+          "title": "Building a Template-driven Form",
+          "tooltip": "Create a template-driven form using directives and Angular template syntax."
         }
       ]
     },
@@ -772,13 +693,13 @@
           "tooltip": "Angular versioning, release, support, and deprecation policies and practices."
         },
         {
-          "title": "Updating to Version 9",
-          "tooltip": "Support for updating your application from version 8 to 9.",
+          "title": "Updating to Version 10",
+          "tooltip": "Support for updating your application from version 9 to 10.",
           "children": [
             {
-              "url": "guide/updating-to-version-9",
+              "url": "guide/updating-to-version-10",
               "title": "Overview",
-              "tooltip": "Everything you need to know for updating your application from version 8 to 9."
+              "tooltip": "Everything you need to know for updating your application from version 9 to 10."
             },
             {
               "url": "guide/ivy-compatibility",
@@ -786,29 +707,9 @@
               "tooltip": "Details to help you make sure your application is compatible with Ivy."
             },
             {
-              "title": "Optional Migrations",
-              "tooltip": "Optional migration details regarding updating to version 9.",
+              "title": "Migrations",
+              "tooltip": "Migration details regarding updating to version 10.",
               "children": [
-                {
-                  "url": "guide/migration-renderer",
-                  "title": "Renderer to Renderer2",
-                  "tooltip": "Migration from the deprecated Renderer API to the newer Renderer2 API."
-                },
-                {
-                  "url": "guide/migration-dynamic-flag",
-                  "title": "Dynamic Queries Flag",
-                  "tooltip": "Migration to remove unnecessary `static: false` flag from @ViewChild and @ContentChild queries."
-                },
-                {
-                  "url": "guide/migration-injectable",
-                  "title": "Missing @Injectable() Decorators",
-                  "tooltip": "Migration to add missing @Injectable() decorators and incomplete provider definitions."
-                },
-                {
-                  "url": "guide/migration-localize",
-                  "title": "$localize Global Import",
-                  "tooltip": "Migration to add an import statement for @angular/localize to polyfills.ts."
-                },
                 {
                   "url": "guide/migration-module-with-providers",
                   "title": "Missing ModuleWithProviders Generic",
@@ -818,6 +719,26 @@
                   "url": "guide/migration-undecorated-classes",
                   "title": "Missing @Directive() Decorators",
                   "tooltip": "Migration to add missing @Directive()/@Component() decorators."
+                },
+                {
+                  "url": "guide/migration-injectable",
+                  "title": "Missing @Injectable() Decorators",
+                  "tooltip": "Migration to add missing @Injectable() decorators and incomplete provider definitions."
+                },
+                {
+                  "url": "guide/migration-solution-style-tsconfig",
+                  "title": "Solution-style `tsconfig.json`",
+                  "tooltip": "Migration to create a solution-style `tsconfig.json`."
+                },
+                {
+                  "url": "guide/migration-update-libraries-tslib",
+                  "title": "`tslib` direct dependency",
+                  "tooltip": "Migration to a direct dependency on the `tslib` npm package."
+                },
+                {
+                  "url": "guide/migration-update-module-and-target-compiler-options",
+                  "title": "`module` and `target` compiler options",
+                  "tooltip": "Migration to update `module` and `target` compiler options."
                 }
               ]
             }
@@ -1013,6 +934,10 @@
     }
   ],
   "docVersions": [
+    {
+      "title": "v9",
+      "url": "https://v9.angular.io/"
+    },
     {
       "title": "v8",
       "url": "https://v8.angular.io/"

aio/content/tutorial/index.md

@@ -6,7 +6,7 @@
 In this tutorial, you build your own app from the ground up, providing experience with the typical development process, as well as an introduction to basic app-design concepts, tools, and terminology.
 
 If you're completely new to Angular, you might want to try the [**Try it now**](start) quick-start app first.
-It is based on a ready-made  partially-completed project, which you can examine and modify in the StacBlitz interactive development environment, where you can see the results in real time.
+It is based on a ready-made  partially-completed project, which you can examine and modify in the StackBlitz interactive development environment, where you can see the results in real time.
 
 The "Try it" tutorial covers the same major topics—components, template syntax, routing, services, and accessing data via HTTP—in a condensed format, following the most current best practices.
 

aio/content/tutorial/toh-pt0.md

@@ -9,6 +9,11 @@ In this part of the tutorial, you'll do the following:
 3. Serve the application.
 4. Make changes to the application.
 
+<div class="alert is-helpful">
+
+  For the sample app that this page describes, see the <live-example></live-example>.
+
+</div>
 
 ## Set up your environment
 
@@ -113,9 +118,6 @@ Open `src/styles.css` and add the code below to the file.
 
 ## Final code review
 
-The source code for this tutorial and the complete _Tour of Heroes_ global styles
-are available in the <live-example></live-example>.
-
 Here are the code files discussed on this page.
 
 <code-tabs>

aio/content/tutorial/toh-pt1.md

@@ -4,6 +4,12 @@ The application now has a basic title.
 Next you will create a new component to display hero information
 and place that component in the application shell.
 
+<div class="alert is-helpful">
+
+  For the sample app that this page describes, see the <live-example></live-example>.
+
+</div>
+
 ## Create the heroes component
 
 Using the Angular CLI, generate a new component named `heroes`.
@@ -201,7 +207,7 @@ Note that `AppModule`  declares both application components, `AppComponent` and
 
 ## Final code review
 
-Your app should look like this <live-example></live-example>. Here are the code files discussed on this page.
+Here are the code files discussed on this page.
 
 <code-tabs>
 

aio/content/tutorial/toh-pt2.md

@@ -3,6 +3,12 @@
 In this page, you'll expand the Tour of Heroes app to display a list of heroes, and
 allow users to select a hero and display the hero's details.
 
+<div class="alert is-helpful">
+
+  For the sample app that this page describes, see the <live-example></live-example>.
+
+</div>
+
 
 ## Create mock heroes
 
@@ -220,8 +226,6 @@ The finished `<li>` looks like this:
 
 ## Final code review
 
-Your app should look like this <live-example></live-example>.
-
 Here are the code files discussed on this page, including the `HeroesComponent` styles.
 
 <code-tabs>

aio/content/tutorial/toh-pt3.md

@@ -10,6 +10,12 @@ In this page, you'll take the first step in that direction by moving the hero de
 The `HeroesComponent` will only present the list of heroes.
 The `HeroDetailComponent` will present details of a selected hero.
 
+<div class="alert is-helpful">
+
+  For the sample app that this page describes, see the <live-example></live-example>.
+
+</div>
+
 ## Make the `HeroDetailComponent`
 
 Use the Angular CLI to generate a new component named `hero-detail`.
@@ -136,7 +142,7 @@ without touching the parent `HeroesComponent`.
 
 ## Final code review
 
-Here are the code files discussed on this page and your app should look like this <live-example></live-example>.
+Here are the code files discussed on this page.
 
 <code-tabs>
 

aio/content/tutorial/toh-pt4.md

@@ -5,6 +5,13 @@ The Tour of Heroes `HeroesComponent` is currently getting and displaying fake da
 After the refactoring in this tutorial, `HeroesComponent` will be lean and focused on supporting the view.
 It will also be easier to unit-test with a mock service.
 
+<div class="alert is-helpful">
+
+  For the sample app that this page describes, see the <live-example></live-example>.
+
+</div>
+
+
 ## Why services
 
 Components shouldn't fetch or save data directly and they certainly shouldn't knowingly present fake data.
@@ -132,7 +139,7 @@ sets the `heroService` parameter to the singleton instance of `HeroService`.
 
 ### Add `getHeroes()`
 
-Create a function to retrieve the heroes from the service.
+Create a method to retrieve the heroes from the service.
 
 <code-example path="toh-pt4/src/app/heroes/heroes.component.1.ts" header="src/app/heroes/heroes.component.ts" region="getHeroes">
 </code-example>
@@ -387,7 +394,7 @@ the selection. Use the "clear" button to clear the message history.
 
 ## Final code review
 
-Here are the code files discussed on this page and your app should look like this <live-example></live-example>.
+Here are the code files discussed on this page.
 
 <code-tabs>
 

aio/content/tutorial/toh-pt5.md

@@ -7,6 +7,12 @@ There are new requirements for the Tour of Heroes app:
 * When users click a hero name in either view, navigate to a detail view of the selected hero.
 * When users click a *deep link* in an email, open the detail view for a particular hero.
 
+<div class="alert is-helpful">
+
+  For the sample app that this page describes, see the <live-example></live-example>.
+
+</div>
+
 When you’re done, users will be able to navigate the app like this:
 
 <div class="lightbox">
@@ -466,7 +472,7 @@ from heroes list to the mini detail to the hero details and back to the heroes a
 
 ## Final code review
 
-Here are the code files discussed on this page and your app should look like this <live-example></live-example>.
+Here are the code files discussed on this page.
 
 {@a approutingmodule}
 {@a appmodule}

aio/content/tutorial/toh-pt6.md

@@ -7,7 +7,11 @@ Angular's `HttpClient`.
 * Users can add, edit, and delete heroes and save these changes over HTTP.
 * Users can search for heroes by name.
 
-When you're done with this page, the app should look like this <live-example></live-example>.
+<div class="alert is-helpful">
+
+  For the sample app that this page describes, see the <live-example></live-example>.
+
+</div>
 
 ## Enable HTTP services
 
@@ -75,7 +79,8 @@ Replace the default contents of `in-memory-data.service.ts` with the following:
 
 <code-example path="toh-pt6/src/app/in-memory-data.service.ts" region="init" header="src/app/in-memory-data.service.ts"></code-example>
 
-The `in-memory-data.service.ts` file replaces `mock-heroes.ts`, which is now safe to delete.
+The `in-memory-data.service.ts` file will take over the function of `mock-heroes.ts`.
+However, don't delete `mock-heroes.ts` yet, as you still need it for a few more steps of this tutorial.
 
 When the server is ready, you'll detach the In-memory Web API, and the app's requests will go through to the server.
 
@@ -519,8 +524,6 @@ If you enter characters that match any existing hero names, you'll see something
 
 ## Final code review
 
-Your app should look like this <live-example></live-example>.
-
 Here are the code files discussed on this page (all in the `src/app/` folder).
 
 {@a heroservice}

aio/firebase.json

@@ -1,5 +1,6 @@
 {
   "hosting": {
+    "target": "aio",
     "public": "dist",
     "cleanUrls": true,
     "redirects": [
@@ -18,6 +19,7 @@
       {"type": 301, "source": "/docs/*/latest/quickstart.html", "destination": "/start"},
       {"type": 301, "source": "/docs/*/latest/guide/server-communication.html", "destination": "/guide/http"},
       {"type": 301, "source": "/docs/*/latest/guide/style-guide.html", "destination": "/guide/styleguide"},
+      {"type": 301, "source": "/guide/bazel", "destination": "https://github.com/angular/angular/blob/master/packages/bazel/src/schematics/README.md"},
       {"type": 301, "source": "/guide/cli-quickstart", "destination": "/start"},
       {"type": 301, "source": "/guide/service-worker-getstart", "destination": "/guide/service-worker-getting-started"},
       {"type": 301, "source": "/guide/service-worker-comm", "destination": "/guide/service-worker-communications"},
@@ -121,7 +123,12 @@
       // Strip off the `.html` extension, because Firebase will not do this automatically any more
       // (unless the new URL points to an existing file, which is not necessarily the case here).
       {"type": 301, "source": "/:somePath*/:file.html", "destination": "/:somePath*/:file"},
-      {"type": 301, "source": "/:topLevelFile.html", "destination": "/:topLevelFile"}
+      {"type": 301, "source": "/:topLevelFile.html", "destination": "/:topLevelFile"},
+
+      // The below paths are referenced in users projects generated by the CLI
+      {"type": 301, "source": "/config/tsconfig", "destination": "/guide/typescript-configuration"},
+      {"type": 301, "source": "/config/solution-tsconfig", "destination": "https://devblogs.microsoft.com/typescript/announcing-typescript-3-9/#solution-style-tsconfig"},
+      {"type": 301, "source": "/config/app-package-json", "destination": "/guide/strict-mode#non-local-side-effects-in-applications"}
     ],
     "rewrites": [
       {

aio/ngsw-config.json

@@ -94,6 +94,7 @@
     "!/api/testing/**",
     "!/docs/?*",
     "!/docs/*/**",
+    "!/guide/bazel",
     "!/guide/change-log",
     "!/getting-started",
     "!/getting-started.html",
@@ -146,6 +147,7 @@
     "!/styleguide",
     "!/styleguide/**",
     "!/testing",
-    "!/testing/**"
+    "!/testing/**",
+    "!/config/**"
   ]
 }

aio/package.json

@@ -23,7 +23,7 @@
     "build-local-with-viewengine": "yarn ~~build",
     "prebuild-local-with-viewengine-ci": "node scripts/switch-to-viewengine && yarn setup-local-ci",
     "build-local-with-viewengine-ci": "yarn ~~build --progress=false",
-    "extract-cli-command-docs": "node tools/transforms/cli-docs-package/extract-cli-commands.js 200a21f8a",
+    "extract-cli-command-docs": "node tools/transforms/cli-docs-package/extract-cli-commands.js 14af4e07c",
     "lint": "yarn check-env && yarn docs-lint && ng lint && yarn example-lint && yarn tools-lint",
     "test": "yarn check-env && ng test",
     "pree2e": "yarn check-env && yarn update-webdriver",
@@ -87,28 +87,28 @@
   },
   "private": true,
   "dependencies": {
-    "@angular/animations": "10.0.0-next.5",
+    "@angular/animations": "10.0.0-rc.2",
     "@angular/cdk": "^9.2.2",
-    "@angular/common": "10.0.0-next.5",
-    "@angular/compiler": "10.0.0-next.5",
-    "@angular/core": "10.0.0-next.5",
-    "@angular/elements": "10.0.0-next.5",
-    "@angular/forms": "10.0.0-next.5",
+    "@angular/common": "10.0.0-rc.2",
+    "@angular/compiler": "10.0.0-rc.2",
+    "@angular/core": "10.0.0-rc.2",
+    "@angular/elements": "10.0.0-rc.2",
+    "@angular/forms": "10.0.0-rc.2",
     "@angular/material": "^9.2.2",
-    "@angular/platform-browser": "10.0.0-next.5",
-    "@angular/platform-browser-dynamic": "10.0.0-next.5",
-    "@angular/router": "10.0.0-next.5",
-    "@angular/service-worker": "10.0.0-next.5",
+    "@angular/platform-browser": "10.0.0-rc.2",
+    "@angular/platform-browser-dynamic": "10.0.0-rc.2",
+    "@angular/router": "10.0.0-rc.2",
+    "@angular/service-worker": "10.0.0-rc.2",
     "@webcomponents/custom-elements": "1.2.1",
     "rxjs": "^6.5.3",
     "tslib": "^1.10.0",
     "zone.js": "~0.10.3"
   },
   "devDependencies": {
-    "@angular-devkit/build-angular": "0.1000.0-next.3",
-    "@angular/cli": "10.0.0-next.3",
-    "@angular/compiler-cli": "10.0.0-next.5",
-    "@angular/language-service": "10.0.0-next.5",
+    "@angular-devkit/build-angular": "0.1000.0-rc.2",
+    "@angular/cli": "10.0.0-rc.2",
+    "@angular/compiler-cli": "10.0.0-rc.2",
+    "@angular/language-service": "10.0.0-rc.2",
     "@types/jasmine": "^3.4.2",
     "@types/jasminewd2": "^2.0.8",
     "@types/lunr": "^2.3.2",
@@ -123,7 +123,7 @@
     "cross-spawn": "^5.1.0",
     "css-selector-parser": "^1.3.0",
     "dgeni": "^0.4.11",
-    "dgeni-packages": "^0.28.3",
+    "dgeni-packages": "^0.28.4",
     "entities": "^1.1.1",
     "eslint": "^3.19.0",
     "eslint-plugin-jasmine": "^2.2.0",
@@ -154,7 +154,7 @@
     "lunr": "^2.1.0",
     "npm-run-all": "^4.1.5",
     "protractor": "~5.4.4",
-    "puppeteer": "2.1.1",
+    "puppeteer": "3.3.0",
     "rehype": "^6.0.0",
     "rehype-slug": "^2.0.0",
     "remark": "^9.0.0",
@@ -165,7 +165,7 @@
     "tree-kill": "^1.1.0",
     "ts-node": "^8.4.1",
     "tslint": "~6.1.0",
-    "typescript": "~3.8.3",
+    "typescript": "~3.9.5",
     "uglify-js": "^3.0.15",
     "unist-util-filter": "^0.2.1",
     "unist-util-source": "^1.0.1",
@@ -175,4 +175,4 @@
     "xregexp": "^4.0.0",
     "yargs": "^7.0.2"
   }
-}
+}

aio/scripts/deploy-to-firebase.sh

@@ -33,7 +33,7 @@ else
   readonly majorVersionStable=${CI_STABLE_BRANCH%%.*}
 
   # Do not deploy if the major version is not less than the stable branch major version
-  if [[ !( "$majorVersion" < "$majorVersionStable" ) ]]; then
+  if (( $majorVersion >= $majorVersionStable )); then
     echo "Skipping deploy of branch \"$CI_BRANCH\" to firebase."
     echo "We only deploy archive branches with the major version less than the stable branch: \"$CI_STABLE_BRANCH\""
     exit 0
@@ -64,16 +64,27 @@ fi
 case $deployEnv in
   next)
     readonly projectId=aio-staging
+    readonly siteId=$projectId
     readonly deployedUrl=https://next.angular.io/
     readonly firebaseToken=$CI_SECRET_AIO_DEPLOY_FIREBASE_TOKEN
     ;;
   stable)
     readonly projectId=angular-io
+    readonly siteId=$projectId
     readonly deployedUrl=https://angular.io/
     readonly firebaseToken=$CI_SECRET_AIO_DEPLOY_FIREBASE_TOKEN
     ;;
   archive)
-    readonly projectId=v${majorVersion}-angular-io
+    # Special case v9-angular-io because its piloting the firebase hosting "multisites" setup
+    # See https://angular-team.atlassian.net/browse/DEV-125 for more info.
+    if [[ "$majorVersion" == "9" ]]; then
+      readonly projectId=aio-staging
+      readonly siteId=v9-angular-io
+    else
+      readonly projectId=v${majorVersion}-angular-io
+      readonly siteId=$projectId
+    fi
+
     readonly deployedUrl=https://v${majorVersion}.angular.io/
     readonly firebaseToken=$CI_SECRET_AIO_DEPLOY_FIREBASE_TOKEN
     ;;
@@ -82,6 +93,7 @@ esac
 echo "Git branch        : $CI_BRANCH"
 echo "Build/deploy mode : $deployEnv"
 echo "Firebase project  : $projectId"
+echo "Firebase site     : $siteId"
 echo "Deployment URL    : $deployedUrl"
 
 if [[ ${1:-} == "--dry-run" ]]; then
@@ -92,23 +104,29 @@ fi
 (
   cd "`dirname $0`/.."
 
-  # Build the app
+  echo "\n\n\n==== Build the aio app ====\n"
   yarn build --configuration=$deployEnv --progress=false
 
-  # Include any mode-specific files
+
+  echo "\n\n\n==== Add any mode-specific files into the aio distribution ====\n"
   cp -rf src/extra-files/$deployEnv/. dist/
 
-  # Set deployedUrl as parameter in the opensearch description
+
+  echo "\n\n\n==== Update opensearch descriptor for aio with the deployedUrl ====\n"
   # deployedUrl must end with /
   yarn set-opensearch-url $deployedUrl
 
-  # Check payload size
+  echo "\n\n\n==== Check payload size and upload the numbers to firebase db ====\n"
   yarn payload-size
 
-  # Deploy to Firebase
-  yarn firebase use "$projectId" --token "$firebaseToken"
-  yarn firebase deploy --message "Commit: $CI_COMMIT" --non-interactive --token "$firebaseToken"
 
-  # Run PWA-score tests
+  echo "\n\n\n==== Deploy aio to firebase hosting ====\n"
+
+  yarn firebase use "${projectId}" --token "$firebaseToken"
+  yarn firebase target:apply hosting aio $siteId --token "$firebaseToken"
+  yarn firebase deploy --only hosting:aio --message "Commit: $CI_COMMIT" --non-interactive --token "$firebaseToken"
+
+
+  echo "\n\n\n==== Run PWA-score tests ====\n"
   yarn test-pwa-score "$deployedUrl" "$CI_AIO_MIN_PWA_SCORE"
 )

aio/scripts/deploy-to-firebase.test.sh

@@ -68,6 +68,7 @@ function check {
   expected="Git branch        : master
 Build/deploy mode : next
 Firebase project  : aio-staging
+Firebase site     : aio-staging
 Deployment URL    : https://next.angular.io/"
   check "$actual" "$expected"
 )
@@ -103,6 +104,7 @@ Deployment URL    : https://next.angular.io/"
   expected="Git branch        : 4.3.x
 Build/deploy mode : stable
 Firebase project  : angular-io
+Firebase site     : angular-io
 Deployment URL    : https://angular.io/"
   check "$actual" "$expected"
 )
@@ -139,10 +141,37 @@ Deployment URL    : https://angular.io/"
   expected="Git branch        : 2.4.x
 Build/deploy mode : archive
 Firebase project  : v2-angular-io
+Firebase site     : v2-angular-io
 Deployment URL    : https://v2.angular.io/"
   check "$actual" "$expected"
 )
 
+(
+  echo ===== archive - v9-angular-io multisite special case - deploy success
+  actual=$(
+    export BASH_ENV=/dev/null
+    export CI_REPO_OWNER=angular
+    export CI_REPO_NAME=angular
+    export CI_PULL_REQUEST=false
+    export CI_BRANCH=9.1.x
+    export CI_STABLE_BRANCH=10.0.x
+    export CI_COMMIT=$(git ls-remote origin 9.1.x | cut -c1-40)
+    export CI_SECRET_AIO_DEPLOY_FIREBASE_TOKEN=XXXXX
+    $deployToFirebaseDryRun
+  )
+  expected="Git branch        : 9.1.x
+Build/deploy mode : archive
+Firebase project  : aio-staging
+Firebase site     : v9-angular-io
+Deployment URL    : https://v9.angular.io/"
+  # TODO: This test incorrectly expects the Firebase project to be v9-angular-io.
+  #       v9-angular-io is a "multisites" project currently within the aio-staging project
+  #       This setup is temporary and was created in order to deploy v9.angular.io without
+  #       disruptions.
+  #       See https://angular-team.atlassian.net/browse/DEV-125 for more info.
+  check "$actual" "$expected"
+)
+
 (
   echo ===== archive - skip deploy - commit not HEAD
   actual=$(

aio/src/app/app.component.html

@@ -5,13 +5,9 @@
 </div>
 
 <mat-toolbar color="primary" class="app-toolbar no-print" [class.transitioning]="isTransitioning">
-  <mat-toolbar-row class="notification-container">
-    <aio-notification notificationId="survey-march-2020" expirationDate="2020-04-15" [dismissOnContentClick]="true" (dismissed)="notificationDismissed()">
-      <a href="https://goo.gle/angular-survey-2020">
-        <mat-icon class="icon" svgIcon="insert_comment" aria-label="Announcement"></mat-icon>
-        <span class="message">Help Angular by taking a <b>1 minute survey</b>!</span>
-        <span class="action-button">Go to survey</span>
-      </a>
+  <mat-toolbar-row class="notification-container blm-message">
+    <aio-notification notificationId="blm-2020" expirationDate="2022-04-15" [dismissOnContentClick]="true" (dismissed)="notificationDismissed()">
+      #BlackLivesMatter
     </aio-notification>
   </mat-toolbar-row>
   <mat-toolbar-row>

aio/src/app/layout/doc-viewer/doc-viewer.component.spec.ts

@@ -401,7 +401,10 @@ describe('DocViewerComponent', () => {
         expect(loadElementsSpy.calls.argsFor(1)).toEqual([docViewer.nextViewContainer]);
       });
 
-      it('should unsubscribe from the previous "embed" observable when unsubscribed from', () => {
+      // This test sometimes incorrectly fails on CI.
+      // Reported in https://github.com/angular/angular/issues/37629.
+      // Investigated in https://github.com/angular/angular/pull/37637.
+      xit('should unsubscribe from the previous "embed" observable when unsubscribed from', () => {
         const obs = new ObservableWithSubscriptionSpies();
         loadElementsSpy.and.returnValue(obs);
 
@@ -436,7 +439,10 @@ describe('DocViewerComponent', () => {
         expect(swapViewsSpy).toHaveBeenCalledWith(addTitleAndTocSpy);
       });
 
-      it('should unsubscribe from the previous "swap" observable when unsubscribed from', () => {
+      // This test sometimes incorrectly fails on CI.
+      // Reported in https://github.com/angular/angular/issues/37629.
+      // Investigated in https://github.com/angular/angular/pull/37637.
+      xit('should unsubscribe from the previous "swap" observable when unsubscribed from', () => {
         const obs = new ObservableWithSubscriptionSpies();
         swapViewsSpy.and.returnValue(obs);
 

aio/src/styles/0-base/_typography.scss

@@ -193,6 +193,11 @@ code {
   }
 }
 
+// The following css rule adds an icon to external links in the docs area.
+// The following `folder-*` classes are applied to the `doc-viewer`component when it is displaying docs for these areas of the documentation.
+// We add the icon to all external links which are identified as absolute links (those that start with `http` or https`).
+// For more info see PR #36601
+
 .folder-api,
 .folder-cli,
 .folder-docs,
@@ -213,6 +218,8 @@ code {
       }
     }
 
+    // The docs-viewer also contain links to GitHub (e.g. the edit this page icon) identified with `.github-links` class.
+    // We don't want to add the external link icon to these links, so we hide them.
     .github-links a {
       &[href^="http:"]::after,
       &[href^="https:"]::after {

aio/src/styles/1-layouts/_marketing-layout.scss

@@ -183,8 +183,8 @@ section#intro {
 
 // ANGULAR LINE
 .background-sky {
-  background-color: $blue;
-  background: $bluegradient;
+  background-color: $black;
+  background: $black;
   color: $white;
 }
 

aio/src/styles/1-layouts/_top-menu.scss

@@ -20,9 +20,16 @@ mat-toolbar.mat-toolbar {
   }
 }
 
+.blm-message {
+  text-align: center;
+  justify-content: center;
+  background: #2d2d2d;
+  font-size: 0.75em;
+}
+
 // HOME PAGE OVERRIDE: TOPNAV TOOLBAR
 aio-shell.page-home mat-toolbar.mat-toolbar {
-  background-color: $blue;
+  background-color: $black;
 
   @media (min-width: 481px) {
     &:not(.transitioning) {

aio/src/styles/2-modules/_contributor.scss

@@ -52,16 +52,18 @@ aio-contributor {
   transition: all .3s;
   perspective: 800px;
 
-  &:hover {
-    transform: translate3d(0,-3px,0);
-    box-shadow: 0 8px 8px rgba(10, 16, 20, 0.24), 0 0 8px rgba(10, 16, 20, 0.12);
+  @media (hover) {
+    &:hover {
+      transform: translate3d(0,-3px,0);
+      box-shadow: 0 8px 8px rgba(10, 16, 20, 0.24), 0 0 8px rgba(10, 16, 20, 0.12);
 
-    .contributor-image {
-      transform: scale(1.05);
-    }
+      .contributor-image {
+        transform: scale(1.05);
+      }
 
-    .contributor-info {
-      opacity: 1;
+      .contributor-info {
+        opacity: 1;
+      }
     }
   }
 

aio/tests/e2e/src/api-list.e2e-spec.ts

@@ -0,0 +1,52 @@
+import { by, element } from 'protractor';
+import { SitePage } from './app.po';
+
+describe('api-list', () => {
+  const apiSearchInput = element(by.css('aio-api-list .form-search input'));
+  const apiStatusDropdown = element(by.css('aio-api-list aio-select[label="Status:"]'));
+  const apiTypeDropdown = element(by.css('aio-api-list aio-select[label="Type:"]'));
+  let page: SitePage;
+
+  beforeEach(() => {
+    page = new SitePage();
+    page.navigateTo('api');
+  });
+
+  it('should find AnimationSequenceMetadata when searching by partial word anima', () => {
+    expect(page.getApiSearchResults()).toContain('HttpEventType');
+
+    apiSearchInput.clear();
+    apiSearchInput.sendKeys('anima');
+
+    expect(page.getApiSearchResults()).not.toContain('HttpEventType');
+    expect(page.getApiSearchResults()).toContain('AnimationSequenceMetadata');
+  });
+
+  it('should find getLocaleDateTimeFormat when searching by partial word date', () => {
+    expect(page.getApiSearchResults()).toContain('formatCurrency');
+
+    apiSearchInput.clear();
+    apiSearchInput.sendKeys('date');
+
+    expect(page.getApiSearchResults()).not.toContain('formatCurrency');
+    expect(page.getApiSearchResults()).toContain('getLocaleDateTimeFormat');
+  });
+
+  it('should find LowerCasePipe when searching for type pipe', () => {
+    expect(page.getApiSearchResults()).toContain('getLocaleDateTimeFormat');
+
+    page.clickDropdownItem(apiTypeDropdown, 'Pipe');
+
+    expect(page.getApiSearchResults()).not.toContain('getLocaleDateTimeFormat');
+    expect(page.getApiSearchResults()).toContain('LowerCasePipe');
+  });
+
+  it('should find ElementRef when searching for status Security Risk', () => {
+    expect(page.getApiSearchResults()).toContain('getLocaleDateTimeFormat');
+
+    page.clickDropdownItem(apiStatusDropdown, 'Security Risk');
+
+    expect(page.getApiSearchResults()).not.toContain('getLocaleDateTimeFormat');
+    expect(page.getApiSearchResults()).toContain('ElementRef');
+  });
+});

aio/tests/e2e/src/app.po.ts

@@ -83,4 +83,16 @@ export class SitePage {
     browser.wait(ExpectedConditions.presenceOf(results.first()), 8000);
     return results.map(link => link && link.getText());
   }
+
+  getApiSearchResults() {
+    const results = element.all(by.css('aio-api-list .api-item'));
+    browser.wait(ExpectedConditions.presenceOf(results.first()), 2000);
+    return results.map(elem => elem && elem.getText());
+  }
+
+  clickDropdownItem(dropdown: ElementFinder, itemName: string){
+    dropdown.element(by.css('.form-select-button')).click();
+    const menuItem = dropdown.element(by.cssContainingText('.form-select-dropdown li', itemName));
+    menuItem.click();
+  }
 }