feat(@angular/build): add --list-tests flag to unit-test builder

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

@@ -225,6 +225,7 @@ export type UnitTestBuilderOptions = {
     exclude?: string[];
     filter?: string;
     include?: string[];
+    listTests?: boolean;
     outputFile?: string;
     progress?: boolean;
     providersFile?: string;

packages/angular/build/src/builders/karma/find-tests.ts

@@ -6,157 +6,6 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-import { PathLike, constants, promises as fs } from 'node:fs';
-import { basename, dirname, extname, join, relative } from 'node:path';
-import { glob, isDynamicPattern } from 'tinyglobby';
-import { toPosixPath } from '../../utils/path';
-
-/* Go through all patterns and find unique list of files */
-export async function findTests(
-  include: string[],
-  exclude: string[],
-  workspaceRoot: string,
-  projectSourceRoot: string,
-): Promise<string[]> {
-  const matchingTestsPromises = include.map((pattern) =>
-    findMatchingTests(pattern, exclude, workspaceRoot, projectSourceRoot),
-  );
-  const files = await Promise.all(matchingTestsPromises);
-
-  // Unique file names
-  return [...new Set(files.flat())];
-}
-
-interface TestEntrypointsOptions {
-  projectSourceRoot: string;
-  workspaceRoot: string;
-  removeTestExtension?: boolean;
-}
-
-/** Generate unique bundle names for a set of test files. */
-export function getTestEntrypoints(
-  testFiles: string[],
-  { projectSourceRoot, workspaceRoot, removeTestExtension }: TestEntrypointsOptions,
-): Map<string, string> {
-  const seen = new Set<string>();
-
-  return new Map(
-    Array.from(testFiles, (testFile) => {
-      const relativePath = removeRoots(testFile, [projectSourceRoot, workspaceRoot])
-        // Strip leading dots and path separators.
-        .replace(/^[./\\]+/, '')
-        // Replace any path separators with dashes.
-        .replace(/[/\\]/g, '-');
-
-      let fileName = basename(relativePath, extname(relativePath));
-      if (removeTestExtension) {
-        fileName = fileName.replace(/\.(spec|test)$/, '');
-      }
-
-      const baseName = `spec-${fileName}`;
-      let uniqueName = baseName;
-      let suffix = 2;
-      while (seen.has(uniqueName)) {
-        uniqueName = `${baseName}-${suffix}`.replace(/([^\w](?:spec|test))-([\d]+)$/, '-$2$1');
-        ++suffix;
-      }
-      seen.add(uniqueName);
-
-      return [uniqueName, testFile];
-    }),
-  );
-}
-
-const removeLeadingSlash = (pattern: string): string => {
-  if (pattern.charAt(0) === '/') {
-    return pattern.substring(1);
-  }
-
-  return pattern;
-};
-
-const removeRelativeRoot = (path: string, root: string): string => {
-  if (path.startsWith(root)) {
-    return path.substring(root.length);
-  }
-
-  return path;
-};
-
-function removeRoots(path: string, roots: string[]): string {
-  for (const root of roots) {
-    if (path.startsWith(root)) {
-      return path.substring(root.length);
-    }
-  }
-
-  return basename(path);
-}
-
-async function findMatchingTests(
-  pattern: string,
-  ignore: string[],
-  workspaceRoot: string,
-  projectSourceRoot: string,
-): Promise<string[]> {
-  // normalize pattern, glob lib only accepts forward slashes
-  let normalizedPattern = toPosixPath(pattern);
-  normalizedPattern = removeLeadingSlash(normalizedPattern);
-
-  const relativeProjectRoot = toPosixPath(relative(workspaceRoot, projectSourceRoot) + '/');
-
-  // remove relativeProjectRoot to support relative paths from root
-  // such paths are easy to get when running scripts via IDEs
-  normalizedPattern = removeRelativeRoot(normalizedPattern, relativeProjectRoot);
-
-  // special logic when pattern does not look like a glob
-  if (!isDynamicPattern(normalizedPattern)) {
-    if (await isDirectory(join(projectSourceRoot, normalizedPattern))) {
-      normalizedPattern = `${normalizedPattern}/**/*.spec.@(ts|tsx)`;
-    } else {
-      // see if matching spec file exists
-      const fileExt = extname(normalizedPattern);
-      // Replace extension to `.spec.ext`. Example: `src/app/app.component.ts`-> `src/app/app.component.spec.ts`
-      const potentialSpec = join(
-        projectSourceRoot,
-        dirname(normalizedPattern),
-        `${basename(normalizedPattern, fileExt)}.spec${fileExt}`,
-      );
-
-      if (await exists(potentialSpec)) {
-        return [potentialSpec];
-      }
-    }
-  }
-
-  // normalize the patterns in the ignore list
-  const normalizedIgnorePatternList = ignore.map((pattern: string) =>
-    removeRelativeRoot(removeLeadingSlash(toPosixPath(pattern)), relativeProjectRoot),
-  );
-
-  return glob(normalizedPattern, {
-    cwd: projectSourceRoot,
-    absolute: true,
-    ignore: ['**/node_modules/**', ...normalizedIgnorePatternList],
-  });
-}
-
-async function isDirectory(path: PathLike): Promise<boolean> {
-  try {
-    const stats = await fs.stat(path);
-
-    return stats.isDirectory();
-  } catch {
-    return false;
-  }
-}
-
-async function exists(path: PathLike): Promise<boolean> {
-  try {
-    await fs.access(path, constants.F_OK);
-
-    return true;
-  } catch {
-    return false;
-  }
-}
+// This file is a compatibility layer that re-exports the test discovery logic from its new location.
+// This is necessary to avoid breaking the Karma builder, which still depends on this file.
+export { findTests, getTestEntrypoints } from '../unit-test/test-discovery';

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

@@ -27,6 +27,7 @@ import { normalizeOptions } from './options';
 import type { TestRunner } from './runners/api';
 import { MissingDependenciesError } from './runners/dependency-checker';
 import type { Schema as UnitTestBuilderOptions } from './schema';
+import { findTests } from './test-discovery';
 
 export type { UnitTestBuilderOptions };
 
@@ -200,6 +201,24 @@ export async function* execute(
     return;
   }
 
+  if (normalizedOptions.listTests) {
+    const testFiles = await findTests(
+      normalizedOptions.include,
+      normalizedOptions.exclude ?? [],
+      normalizedOptions.workspaceRoot,
+      normalizedOptions.projectSourceRoot,
+    );
+
+    context.logger.info('Discovered test files:');
+    for (const file of testFiles) {
+      context.logger.info(`  ${path.relative(normalizedOptions.workspaceRoot, file)}`);
+    }
+
+    yield { success: true };
+
+    return;
+  }
+
   if (runner.isStandalone) {
     try {
       await using executor = await runner.createExecutor(context, normalizedOptions, undefined);

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

@@ -75,6 +75,7 @@ export async function normalizeOptions(
       ? options.setupFiles.map((setupFile) => path.join(workspaceRoot, setupFile))
       : [],
     dumpVirtualFiles: options.dumpVirtualFiles,
+    listTests: options.listTests,
   };
 }
 

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

@@ -148,6 +148,11 @@
       "type": "boolean",
       "description": "Shows build progress information in the console. Defaults to the `progress` setting of the specified `buildTarget`."
     },
+    "listTests": {
+      "type": "boolean",
+      "description": "Lists all discovered test files and exits the process without building or executing the tests.",
+      "default": false
+    },
     "dumpVirtualFiles": {
       "type": "boolean",
       "description": "Dumps build output files to the `.angular/cache` directory for debugging purposes.",