fix(ngcc): do not collect private declarations from external packages (#34811)

Previously, while trying to build an `NgccReflectionHost`'s
`privateDtsDeclarationMap`, `computePrivateDtsDeclarationMap()` would
try to collect exported declarations from all source files of the
program (i.e. without checking whether they were within the target
package, as happens for declarations in `.d.ts` files).

Most of the time, that would not be a problem, because external packages
would be represented as `.d.ts` files in the program. But when an
external package had no typings, the JS files would be used instead. As
a result, the `ReflectionHost` would try to (unnecessarilly) parse the
file in order to extract exported declarations, which in turn would be
harmless in most cases.

There are certain cases, though, where the `ReflectionHost` would throw
an error, because it cannot parse the external package's JS file. This
could happen, for example, in `UmdReflectionHost`, which expects the
file to contain exactly one statement. See #34544 for more details on a
real-world failure.

This commit fixes the issue by ensuring that
`computePrivateDtsDeclarationMap()` will only collect exported
declarations from files within the target package.

Jira issue: [FW-1794](https://angular-team.atlassian.net/browse/FW-1794)

Fixes #34544

PR Close #34811

integration/ngcc/debug-test.sh

@@ -15,7 +15,7 @@ node $(pwd)/../../scripts/build-packages-dist.js
 
 # Workaround https://github.com/yarnpkg/yarn/issues/2165
 # Yarn will cache file://dist URIs and not update Angular code
-readonly cache=../.yarn_local_cache
+export readonly cache=../.yarn_local_cache
 function rm_cache {
   rm -rf $cache
 }

integration/ngcc/package.json

@@ -13,6 +13,7 @@
     "@angular/material": "9.0.0-rc.4",
     "@angular/platform-browser": "file:../../dist/packages-dist/platform-browser",
     "@angular/platform-browser-dynamic": "file:../../dist/packages-dist/platform-browser-dynamic",
+    "@angular/platform-server": "file:../../dist/packages-dist/platform-server",
     "@angular/router": "file:../../dist/packages-dist/router",
     "@types/node": "file:../../node_modules/@types/node",
     "rxjs": "file:../../node_modules/rxjs",

integration/ngcc/test.sh

@@ -140,6 +140,17 @@ assertSucceeded "Expected 'ngcc' to log 'Compiling'."
   assertSucceeded "Expected 'ngcc' to not add trailing commas to factory function parameters in UMD."
 
 
+# Can it compile `@angular/platform-server` in UMD + typings without errors?
+# (The CLI prefers the `main` property (which maps to UMD) over `module` when compiling `@angular/platform-server`.
+# See https://github.com/angular/angular-cli/blob/e36853338/packages/angular_devkit/build_angular/src/angular-cli-files/models/webpack-configs/server.ts#L34)
+  rm -rf node_modules/@angular/platform-server && \
+    yarn install --cache-folder $cache --check-files && \
+    test -d node_modules/@angular/platform-server
+  assertSucceeded "Expected to re-install '@angular/platform-server'."
+
+  ngcc --properties main --target @angular/platform-server
+  assertSucceeded "Expected 'ngcc' to successfully compile '@angular/platform-server' (main)."
+
 # Can it be safely run again (as a noop)?
 # And check that it logged skipping compilation as expected
 ngcc -l debug | grep 'Skipping'

integration/ngcc/yarn.lock

@@ -49,6 +49,12 @@
 "@angular/platform-browser@file:../../dist/packages-dist/platform-browser":
   version "9.0.0-rc.1"
 
+"@angular/platform-server@file:../../dist/packages-dist/platform-server":
+  version "9.0.0-rc.1"
+  dependencies:
+    domino "^2.1.2"
+    xhr2 "^0.1.4"
+
 "@angular/router@file:../../dist/packages-dist/router":
   version "9.0.0-rc.1"
 
@@ -853,6 +859,11 @@ dev-ip@^1.0.1:
   resolved "https://registry.yarnpkg.com/dev-ip/-/dev-ip-1.0.1.tgz#a76a3ed1855be7a012bb8ac16cb80f3c00dc28f0"
   integrity sha1-p2o+0YVb56ASu4rBbLgPPADcKPA=
 
+domino@^2.1.2:
+  version "2.1.4"
+  resolved "https://registry.yarnpkg.com/domino/-/domino-2.1.4.tgz#78922e7fab7c610f35792b6c745b7962d342e9c4"
+  integrity sha512-l70mlQ7IjPKC8kT7GljQXJZmt5OqFL+RE91ik5y5WWQtsd9wP8R7gpFnNu96fK5MqAAZRXfLLsnzKtkty5fWGQ==
+
 easy-extender@^2.3.4:
   version "2.3.4"
   resolved "https://registry.yarnpkg.com/easy-extender/-/easy-extender-2.3.4.tgz#298789b64f9aaba62169c77a2b3b64b4c9589b8f"
@@ -3479,6 +3490,11 @@ ws@~3.3.1:
     safe-buffer "~5.1.0"
     ultron "~1.1.0"
 
+xhr2@^0.1.4:
+  version "0.1.4"
+  resolved "https://registry.yarnpkg.com/xhr2/-/xhr2-0.1.4.tgz#7f87658847716db5026323812f818cadab387a5f"
+  integrity sha1-f4dliEdxbbUCYyOBL4GMras4el8=
+
 xml2js@^0.4.17:
   version "0.4.19"
   resolved "https://registry.yarnpkg.com/xml2js/-/xml2js-0.4.19.tgz#686c20f213209e94abf0d1bcf1efaa291c7827a7"