build: publish tree of files rather than FESMs (#18541)

* Remove now unnecessary portions of build.
* Add a compilePackageES5 method to build ES5 from sources
* Rework all package.json and rollup config files to new format
* Remove "extends" from tsconfig-build.json files and fixup compilation roots

PR Close #18541

packages/common/testing/index.ts

@@ -6,10 +6,9 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-/**
- * @module
- * @description
- * Entry point for all public APIs of the core/testing package.
- */
+// This file is not used to build this module. It is only used during editing
+// by the TypeScript language service and during build for verification. `ngc`
+// replaces this file with production index.ts when it rewrites private symbol
+// names.
 
-export * from './src/testing';
+export * from './public_api';

packages/common/testing/package.json

@@ -1,7 +1,7 @@
 {
   "name": "@angular/common/testing",
-  "typings": "../testing.d.ts",
+  "typings": "./index.d.ts",
   "main": "../bundles/common-testing.umd.js",
-  "module": "../@angular/common/testing.es5.js",
-  "es2015": "../@angular/common/testing.js"
+  "module": "../esm5/testing/index.js",
+  "es2015": "../esm15/testing/index.js"
 }

packages/common/testing/public_api.ts

@@ -0,0 +1,16 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+/**
+ * @module
+ * @description
+ * Entry point for all public APIs of this package.
+ */
+export * from './src/testing';
+
+// This file only reexports content of the `src` folder. Keep it that way.

packages/common/testing/rollup.config.js

@@ -7,6 +7,7 @@
  */
 
 import resolve from 'rollup-plugin-node-resolve';
+import sourcemaps from 'rollup-plugin-sourcemaps';
 
 const globals = {
   '@angular/core': 'ng.core',
@@ -16,12 +17,12 @@ const globals = {
 };
 
 export default {
-  entry: '../../../dist/packages-dist/common/@angular/common/testing.es5.js',
+  entry: '../../../dist/packages-dist/common/esm5/testing/index.js',
   dest: '../../../dist/packages-dist/common/bundles/common-testing.umd.js',
   format: 'umd',
   exports: 'named',
   moduleName: 'ng.common.testing',
-  plugins: [resolve()],
+  plugins: [resolve(), sourcemaps()],
   external: Object.keys(globals),
   globals: globals
 };

packages/common/testing/tsconfig-build.json

@@ -1,17 +1,25 @@
 {
-  "extends": "../tsconfig-build",
+  "extends": "../tsconfig-build.json",
 
   "compilerOptions": {
+    "baseUrl": ".",
+    "rootDir": "../",
     "paths": {
-      "@angular/core": ["../../dist/packages/core"],
-      "@angular/common": ["../../dist/packages/common"]
-    }
+      "@angular/core": ["../../../dist/packages/core"],
+      "@angular/common": ["../../../dist/packages/common"]
+    },
+    "outDir": "../../../dist/packages/common"
   },
+
   "files": [
-    "index.ts",
+    "public_api.ts",
     "../../../node_modules/zone.js/dist/zone.js.d.ts"
   ],
+
   "angularCompilerOptions": {
-    "strictMetadataEmit": true
+    "annotateForClosureCompiler": true,
+    "strictMetadataEmit": true,
+    "flatModuleOutFile": "index.js",
+    "flatModuleId": "@angular/common/testing"
   }
 }