fix: check for existing SW manifest should look in project dir

A previous change broke the logic which brings an application ngsw-manifest.json into the Webpack build for merging with the auto-generated configuration. It caused the GlobCopyWebpackPlugin to look in the wrong directory for the existing manifest. This change sets the working directory for the copy plugin explicitly.

Fixes #6654.

Author: alxhub

packages/@angular/cli/models/webpack-configs/production.ts

@@ -60,6 +60,7 @@ export const getProdConfig = function (wco: WebpackConfigOptions) {
     extraPlugins.push(new GlobCopyWebpackPlugin({
       patterns: ['ngsw-manifest.json', 'src/ngsw-manifest.json'],
       globOptions: {
+        cwd: projectRoot,
         optional: true,
       },
     }));

tests/e2e/tests/build/service-worker.ts

@@ -1,6 +1,6 @@
 import {join} from 'path';
 import {getGlobalVariable} from '../../utils/env';
-import {expectFileToExist, expectFileToMatch} from '../../utils/fs';
+import {expectFileToExist, expectFileToMatch, writeFile, moveFile} from '../../utils/fs';
 import {ng, npm} from '../../utils/process';
 
 export default function() {
@@ -9,6 +9,8 @@ export default function() {
     return Promise.resolve();
   }
 
+  const rootManifest = join(process.cwd(), 'ngsw-manifest.json');
+
   // Can't use the `ng` helper because somewhere the environment gets
   // stuck to the first build done
   return npm('install', '@angular/service-worker')
@@ -18,5 +20,11 @@ export default function() {
     .then(() => expectFileToExist(join(process.cwd(), 'dist/ngsw-manifest.json')))
     .then(() => ng('build', '--prod', '--base-href=/foo/bar'))
     .then(() => expectFileToExist(join(process.cwd(), 'dist/ngsw-manifest.json')))
-    .then(() => expectFileToMatch('dist/ngsw-manifest.json', /"\/foo\/bar\/index.html"/));
+    .then(() => expectFileToMatch('dist/ngsw-manifest.json', /"\/foo\/bar\/index.html"/))
+    .then(() => writeFile(rootManifest, '{"local": true}'))
+    .then(() => ng('build', '--prod'))
+    .then(() => expectFileToMatch('dist/ngsw-manifest.json', /\"local\"/))
+    .then(() => moveFile(rootManifest, join(process.cwd(), 'src/ngsw-manifest.json')))
+    .then(() => ng('build', '--prod'))
+    .then(() => expectFileToMatch('dist/ngsw-manifest.json', /\"local\"/));
 }