feat(@angular/build): add quiet option to suppress build noise in unit tests

The unit-test builder currently triggers a rebuild of the application on each test run in watch mode. This causes the application builder to print a full list of built files on every rebuild, which can be quite noisy and not useful during test development.

This change introduces a `quiet` option to the `@angular/build:unit-test` builder. When enabled, it suppresses the build summary and stats table from the application builder. The option defaults to `true` when running locally to provide a cleaner development experience, and defaults to `false` when running in a CI environment to ensure detailed logs are available for troubleshooting.

Author: clydin

goldens/public-api/angular/build/index.api.md

@@ -237,6 +237,7 @@ export type UnitTestBuilderOptions = {
     outputFile?: string;
     progress?: boolean;
     providersFile?: string;
+    quiet?: boolean;
     reporters?: SchemaReporter[];
     runner?: Runner;
     runnerConfig?: RunnerConfig;

packages/angular/build/src/builders/application/execute-build.ts

@@ -331,7 +331,7 @@ export async function executeBuild(
     );
   }
 
-  if (!jsonLogs) {
+  if (!jsonLogs && !options.quiet) {
     const changedFiles =
       rebuildState && executionResult.findChangedFiles(rebuildState.previousOutputInfo);
     executionResult.addLog(

packages/angular/build/src/builders/application/options.ts

@@ -120,6 +120,11 @@ interface InternalOptions {
    * Used exclusively for tests and shouldn't be used for other kinds of builds.
    */
   instrumentForCoverage?: (filename: string) => boolean;
+
+  /**
+   * Suppress build summary and stats table.
+   */
+  quiet?: boolean;
 }
 
 /** Full set of options for `application` builder. */
@@ -502,6 +507,7 @@ export async function normalizeOptions(
     plugins: extensions?.codePlugins?.length ? extensions?.codePlugins : undefined,
     loaderExtensions,
     jsonLogs: useJSONBuildLogs,
+    quiet: options.quiet,
     colors: supportColor(),
     clearScreen,
     define,

packages/angular/build/src/builders/unit-test/builder.ts

@@ -325,6 +325,7 @@ export async function* execute(
       ...runnerBuildOptions,
       watch: normalizedOptions.watch,
       progress: normalizedOptions.buildProgress ?? buildTargetOptions.progress,
+      quiet: normalizedOptions.quiet,
       ...(normalizedOptions.tsConfig ? { tsConfig: normalizedOptions.tsConfig } : {}),
     } satisfies ApplicationBuilderInternalOptions;
 

packages/angular/build/src/builders/unit-test/options.ts

@@ -121,6 +121,7 @@ export async function normalizeOptions(
     watch,
     debug: options.debug ?? false,
     ui: process.env['CI'] ? false : ui,
+    quiet: options.quiet ?? (process.env['CI'] ? false : true),
     providersFile: options.providersFile && path.join(workspaceRoot, options.providersFile),
     setupFiles: options.setupFiles
       ? options.setupFiles.map((setupFile) => path.join(workspaceRoot, setupFile))

packages/angular/build/src/builders/unit-test/schema.json

@@ -73,6 +73,10 @@
       "type": "boolean",
       "description": "Enables the Vitest UI for interactive test execution. This option is only available for the Vitest runner."
     },
+    "quiet": {
+      "type": "boolean",
+      "description": "Suppresses the verbose build summary and stats table on each rebuild. Defaults to `true` locally and `false` in CI environments."
+    },
     "coverage": {
       "type": "boolean",
       "description": "Enables coverage reporting for tests. If not specified, the coverage configuration from a runner configuration file will be used if present. Otherwise, coverage is disabled by default."

packages/angular/build/src/builders/unit-test/tests/options/quiet_spec.ts

@@ -0,0 +1,87 @@
+/**
+ * @license
+ * Copyright Google LLC 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.dev/license
+ */
+
+import { execute } from '../../index';
+import {
+  BASE_OPTIONS,
+  describeBuilder,
+  UNIT_TEST_BUILDER_INFO,
+  setupApplicationTarget,
+  expectLog,
+  expectNoLog,
+} from '../setup';
+
+describeBuilder(execute, UNIT_TEST_BUILDER_INFO, (harness) => {
+  describe('Option: "quiet"', () => {
+    let originalCI: string | undefined;
+
+    beforeEach(async () => {
+      setupApplicationTarget(harness);
+      originalCI = process.env['CI'];
+    });
+
+    afterEach(() => {
+      if (originalCI !== undefined) {
+        process.env['CI'] = originalCI;
+      } else {
+        delete process.env['CI'];
+      }
+    });
+
+    it('should default to true (quiet) when CI is not set', async () => {
+      delete process.env['CI'];
+
+      harness.useTarget('test', {
+        ...BASE_OPTIONS,
+      });
+
+      const { result, logs } = await harness.executeOnce();
+      expect(result?.success).toBeTrue();
+      // Should not contain the stats table headers
+      expectNoLog(logs, /Initial chunk files/);
+    });
+
+    it('should default to false (verbose) when CI is set', async () => {
+      process.env['CI'] = 'true';
+
+      harness.useTarget('test', {
+        ...BASE_OPTIONS,
+      });
+
+      const { result, logs } = await harness.executeOnce();
+      expect(result?.success).toBeTrue();
+      // Should contain the stats table headers or file listing
+      expectLog(logs, /Application bundle generation complete/);
+    });
+
+    it('should respect quiet: true explicitly', async () => {
+      process.env['CI'] = 'false'; // Ensure CI doesn't interfere if it defaults to false
+
+      harness.useTarget('test', {
+        ...BASE_OPTIONS,
+        quiet: true,
+      });
+
+      const { result, logs } = await harness.executeOnce();
+      expect(result?.success).toBeTrue();
+      expectNoLog(logs, /Initial chunk files/);
+    });
+
+    it('should respect quiet: false explicitly', async () => {
+      harness.useTarget('test', {
+        ...BASE_OPTIONS,
+        quiet: false,
+      });
+
+      const { result, logs } = await harness.executeOnce();
+      expect(result?.success).toBeTrue();
+      // On initial build, it should print the file list
+      expectLog(logs, /Initial/);
+    });
+  });
+});