fix(@schematics/angular): support adding web-worker to pre version 8 applications

Fixes #14791

Author: alan-agius4

packages/schematics/angular/web-worker/index.ts

@@ -5,7 +5,15 @@
  * 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
  */
-import { JsonParseMode, join, normalize, parseJsonAst, strings, tags } from '@angular-devkit/core';
+import {
+  JsonParseMode,
+  dirname,
+  join,
+  normalize,
+  parseJsonAst,
+  strings,
+  tags,
+} from '@angular-devkit/core';
 import {
   Rule, SchematicContext, SchematicsException, Tree,
   apply, applyTemplates, chain, mergeWith, move, noop, url,
@@ -23,7 +31,10 @@ function addConfig(options: WebWorkerOptions, root: string, tsConfigPath: string
     context.logger.debug('updating project configuration.');
 
     // Add worker glob exclusion to tsconfig.app.json.
-    const workerGlob = 'src/**/*.worker.ts';
+    // Projects pre version 8 should to have tsconfig.app.json inside their application
+    const isInSrc = dirname(normalize(tsConfigPath)).endsWith('src');
+    const workerGlob = `${isInSrc ? '' : 'src/'}**/*.worker.ts`;
+
     const buffer = host.read(tsConfigPath);
     if (buffer) {
       const tsCfgAst = parseJsonAst(buffer.toString(), JsonParseMode.Loose);

packages/schematics/angular/web-worker/index_spec.ts

@@ -114,4 +114,17 @@ describe('Web Worker Schematic', () => {
     const { compilerOptions } = JSON.parse(tree.readContent(path));
     expect(compilerOptions.outDir).toBe('./out-tsc/worker');
   });
+
+  it('supports pre version 8 structure', async () => {
+    const workspace = JSON.parse(appTree.readContent('/angular.json'));
+    const tsConfigPath = '/projects/bar/src/tsconfig.app.json';
+    workspace.projects.bar.architect.build.options.tsConfig = tsConfigPath;
+    appTree.overwrite('/angular.json', JSON.stringify(workspace));
+    appTree.rename('projects/bar/tsconfig.app.json', tsConfigPath);
+
+    const tree = await schematicRunner.runSchematicAsync('web-worker', defaultOptions, appTree)
+      .toPromise();
+    const { exclude } = JSON.parse(tree.readContent(tsConfigPath));
+    expect(exclude).toContain('**/*.worker.ts');
+  });
 });