From 42d1091d6a4258476be2a5eb5b006c11ec522415 Mon Sep 17 00:00:00 2001
From: Alex Rickabaugh <alx+alxhub@alxandria.net>
Date: Thu, 7 May 2020 12:57:41 -0700
Subject: [PATCH] fix(compiler-cli): don't try to tag non-ts files as shims
 (#36987)

Some projects include .js source files (via the TypeScript allowJs option).
Previously, the compiler would attempt to tag these files for shims, which
caused errors as the regex used to create shim filenames assumes a .ts file.
This commit fixes the bug by filtering out non-ts files during tagging.

PR Close #36987
---
 .../src/ngtsc/shims/src/reference_tagger.ts   |  4 ++-
 .../ngtsc/shims/test/reference_tagger_spec.ts | 11 ++++++++
 packages/compiler-cli/test/ngtsc/env.ts       |  1 +
 .../compiler-cli/test/ngtsc/ngtsc_spec.ts     | 27 +++++++++++++++++++
 4 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/packages/compiler-cli/src/ngtsc/shims/src/reference_tagger.ts b/packages/compiler-cli/src/ngtsc/shims/src/reference_tagger.ts
index 126bfb982c..ceecb0c514 100644
--- a/packages/compiler-cli/src/ngtsc/shims/src/reference_tagger.ts
+++ b/packages/compiler-cli/src/ngtsc/shims/src/reference_tagger.ts
@@ -9,6 +9,7 @@
 import * as ts from 'typescript';
 
 import {absoluteFrom, absoluteFromSourceFile} from '../../file_system';
+import {isNonDeclarationTsPath} from '../../util/src/typescript';
 
 import {isExtended as isExtendedSf, isShim, NgExtension, sfExtensionData} from './expando';
 import {makeShimFileName} from './util';
@@ -42,7 +43,8 @@ export class ShimReferenceTagger {
    * Tag `sf` with any needed references if it's not a shim itself.
    */
   tag(sf: ts.SourceFile): void {
-    if (!this.enabled || sf.isDeclarationFile || isShim(sf) || this.tagged.has(sf)) {
+    if (!this.enabled || sf.isDeclarationFile || isShim(sf) || this.tagged.has(sf) ||
+        !isNonDeclarationTsPath(sf.fileName)) {
       return;
     }
 
diff --git a/packages/compiler-cli/src/ngtsc/shims/test/reference_tagger_spec.ts b/packages/compiler-cli/src/ngtsc/shims/test/reference_tagger_spec.ts
index 0fae631048..72b96cf84a 100644
--- a/packages/compiler-cli/src/ngtsc/shims/test/reference_tagger_spec.ts
+++ b/packages/compiler-cli/src/ngtsc/shims/test/reference_tagger_spec.ts
@@ -40,6 +40,17 @@ runInEachFileSystem(() => {
       expectReferencedFiles(sf, []);
     });
 
+    it('should not tag .js files', () => {
+      const tagger = new ShimReferenceTagger(['test1', 'test2']);
+
+      const fileName = _('/file.js');
+      const sf = makeArbitrarySf(fileName);
+
+      expectReferencedFiles(sf, []);
+      tagger.tag(sf);
+      expectReferencedFiles(sf, []);
+    });
+
     it('should not tag shim files', () => {
       const tagger = new ShimReferenceTagger(['test1', 'test2']);
       const fileName = _('/file.ts');
diff --git a/packages/compiler-cli/test/ngtsc/env.ts b/packages/compiler-cli/test/ngtsc/env.ts
index f690b0abb3..8161a701e9 100644
--- a/packages/compiler-cli/test/ngtsc/env.ts
+++ b/packages/compiler-cli/test/ngtsc/env.ts
@@ -59,6 +59,7 @@ export class NgtscTestEnvironment {
         "outDir": "built",
         "rootDir": ".",
         "baseUrl": ".",
+        "allowJs": true,
         "declaration": true,
         "target": "es5",
         "newLine": "lf",
diff --git a/packages/compiler-cli/test/ngtsc/ngtsc_spec.ts b/packages/compiler-cli/test/ngtsc/ngtsc_spec.ts
index a3f83888aa..3aaed9fe49 100644
--- a/packages/compiler-cli/test/ngtsc/ngtsc_spec.ts
+++ b/packages/compiler-cli/test/ngtsc/ngtsc_spec.ts
@@ -3540,6 +3540,33 @@ runInEachFileSystem(os => {
         env.tsconfig({'generateNgFactoryShims': true});
       });
 
+      it('should not be generated for .js files', () => {
+        // This test verifies that the compiler does not attempt to generate shim files for non-TS
+        // input files (in this case, other.js).
+        env.write('test.ts', `
+          import {Component, NgModule} from '@angular/core';
+
+          @Component({
+            selector: 'test-cmp',
+            template: 'This is a template',
+          })
+          export class TestCmp {}
+
+          @NgModule({
+            declarations: [TestCmp],
+            exports: [TestCmp],
+          })
+          export class TestModule {}
+        `);
+        env.write('other.js', `
+          export class TestJs {}
+        `);
+
+        expect(env.driveDiagnostics()).toEqual([]);
+        env.assertExists('test.ngfactory.js');
+        env.assertDoesNotExist('other.ngfactory.js');
+      });
+
       it('should be able to depend on an existing factory shim', () => {
         // This test verifies that ngfactory files from the compilations of dependencies are
         // available to import in a fresh compilation. It is derived from a bug observed in g3 where