fix(@angular/build): normalize code coverage include paths to POSIX

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

@@ -16,6 +16,7 @@ import { logMessages, withNoProgress, withSpinner } from '../../tools/esbuild/ut
 import { ChangedFiles } from '../../tools/esbuild/watcher';
 import { shouldWatchRoot } from '../../utils/environment-options';
 import { NormalizedCachedOptions } from '../../utils/normalize-cache';
+import { toPosixPath } from '../../utils/path';
 import { NormalizedApplicationBuildOptions, NormalizedOutputOptions } from './options';
 import {
   ComponentUpdateResult,
@@ -105,7 +106,7 @@ export async function* runEsBuildBuildAction(
       // Ignore the output and cache paths to avoid infinite rebuild cycles
       outputOptions.base,
       cacheOptions.basePath,
-      `${workspaceRoot.replace(/\\/g, '/')}/**/.*/**`,
+      `${toPosixPath(workspaceRoot)}/**/.*/**`,
     ];
 
     // Setup a watcher

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

@@ -9,6 +9,7 @@
 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(
@@ -59,8 +60,6 @@ export function getTestEntrypoints(
   );
 }
 
-const normalizePath = (path: string): string => path.replace(/\\/g, '/');
-
 const removeLeadingSlash = (pattern: string): string => {
   if (pattern.charAt(0) === '/') {
     return pattern.substring(1);
@@ -94,10 +93,10 @@ async function findMatchingTests(
   projectSourceRoot: string,
 ): Promise<string[]> {
   // normalize pattern, glob lib only accepts forward slashes
-  let normalizedPattern = normalizePath(pattern);
+  let normalizedPattern = toPosixPath(pattern);
   normalizedPattern = removeLeadingSlash(normalizedPattern);
 
-  const relativeProjectRoot = normalizePath(relative(workspaceRoot, projectSourceRoot) + '/');
+  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
@@ -125,7 +124,7 @@ async function findMatchingTests(
 
   // normalize the patterns in the ignore list
   const normalizedIgnorePatternList = ignore.map((pattern: string) =>
-    removeRelativeRoot(removeLeadingSlash(normalizePath(pattern)), relativeProjectRoot),
+    removeRelativeRoot(removeLeadingSlash(toPosixPath(pattern)), relativeProjectRoot),
   );
 
   return glob(normalizedPattern, {

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

@@ -14,6 +14,7 @@ import path from 'node:path';
 import { createVirtualModulePlugin } from '../../tools/esbuild/virtual-module-plugin';
 import { assertIsError } from '../../utils/error';
 import { loadEsmModule } from '../../utils/load-esm';
+import { toPosixPath } from '../../utils/path';
 import { buildApplicationInternal } from '../application';
 import type {
   ApplicationBuilderExtensions,
@@ -117,7 +118,7 @@ export async function* execute(
 
   buildTargetOptions.polyfills = injectTestingPolyfills(buildTargetOptions.polyfills);
 
-  const outputPath = path.join(context.workspaceRoot, generateOutputPath());
+  const outputPath = toPosixPath(path.join(context.workspaceRoot, generateOutputPath()));
   const buildOptions: ApplicationBuilderInternalOptions = {
     ...buildTargetOptions,
     watch: normalizedOptions.watch,
@@ -156,10 +157,11 @@ export async function* execute(
         `import { BrowserTestingModule, platformBrowserTesting } from '@angular/platform-browser/testing';`,
         '',
         normalizedOptions.providersFile
-          ? `import providers from './${path
-              .relative(projectSourceRoot, normalizedOptions.providersFile)
-              .replace(/.[mc]?ts$/, '')
-              .replace(/\\/g, '/')}'`
+          ? `import providers from './${toPosixPath(
+              path
+                .relative(projectSourceRoot, normalizedOptions.providersFile)
+                .replace(/.[mc]?ts$/, ''),
+            )}'`
           : 'const providers = [];',
         '',
         // Same as https://github.com/angular/angular/blob/05a03d3f975771bb59c7eefd37c01fa127ee2229/packages/core/testing/src/test_hooks.ts#L21-L29
@@ -406,7 +408,7 @@ function generateCoverageOption(
   return {
     enabled: true,
     excludeAfterRemap: true,
-    include: [`${path.relative(workspaceRoot, outputPath)}/**`],
+    include: [`${toPosixPath(path.relative(workspaceRoot, outputPath))}/**`],
     // Special handling for `reporter` due to an undefined value causing upstream failures
     ...(codeCoverage.reporters
       ? ({ reporter: codeCoverage.reporters } satisfies VitestCoverageOption)

packages/angular/build/src/tools/esbuild/application-code-bundle.ts

@@ -13,6 +13,7 @@ import { extname, relative } from 'node:path';
 import type { NormalizedApplicationBuildOptions } from '../../builders/application/options';
 import { ExperimentalPlatform } from '../../builders/application/schema';
 import { allowMangle } from '../../utils/environment-options';
+import { toPosixPath } from '../../utils/path';
 import {
   SERVER_APP_ENGINE_MANIFEST_FILENAME,
   SERVER_APP_MANIFEST_FILENAME,
@@ -719,9 +720,7 @@ function getEsBuildCommonPolyfillsOptions(
         }
 
         // Generate module contents with an import statement per defined polyfill
-        let contents = polyfillPaths
-          .map((file) => `import '${file.replace(/\\/g, '/')}';`)
-          .join('\n');
+        let contents = polyfillPaths.map((file) => `import '${toPosixPath(file)}';`).join('\n');
 
         // The below should be done after loading `$localize` as otherwise the locale will be overridden.
         if (i18nOptions.shouldInline) {
@@ -746,10 +745,5 @@ function getEsBuildCommonPolyfillsOptions(
 }
 
 function entryFileToWorkspaceRelative(workspaceRoot: string, entryFile: string): string {
-  return (
-    './' +
-    relative(workspaceRoot, entryFile)
-      .replace(/.[mc]?ts$/, '')
-      .replace(/\\/g, '/')
-  );
+  return './' + toPosixPath(relative(workspaceRoot, entryFile).replace(/.[mc]?ts$/, ''));
 }

packages/angular/build/src/tools/esbuild/global-styles.ts

@@ -8,6 +8,7 @@
 
 import assert from 'node:assert';
 import { NormalizedApplicationBuildOptions } from '../../builders/application/options';
+import { toPosixPath } from '../../utils/path';
 import { BundlerOptionsFactory } from './bundler-context';
 import { createStylesheetBundleOptions } from './stylesheets/bundle-options';
 import { createVirtualModulePlugin } from './virtual-module-plugin';
@@ -91,7 +92,7 @@ export function createGlobalStylesBundleOptions(
           assert(files, `global style name should always be found [${args.path}]`);
 
           return {
-            contents: files.map((file) => `@import '${file.replace(/\\/g, '/')}';`).join('\n'),
+            contents: files.map((file) => `@import '${toPosixPath(file)}';`).join('\n'),
             loader: 'css',
             resolveDir: workspaceRoot,
           };

packages/angular/build/src/tools/sass/rebasing-importer.ts

@@ -13,6 +13,7 @@ import { basename, dirname, extname, join, relative } from 'node:path';
 import { fileURLToPath, pathToFileURL } from 'node:url';
 import type { CanonicalizeContext, Importer, ImporterResult, Syntax } from 'sass';
 import { assertIsError } from '../../utils/error';
+import { toPosixPath } from '../../utils/path';
 import { findUrls } from './lexer';
 
 /**
@@ -83,7 +84,7 @@ abstract class UrlRebasingImporter implements Importer<'sync'> {
 
       // Normalize path separators and escape characters
       // https://developer.mozilla.org/en-US/docs/Web/CSS/url#syntax
-      const rebasedUrl = rebasedPath.replace(/\\/g, '/').replace(/[()\s'"]/g, '\\$&');
+      const rebasedUrl = toPosixPath(rebasedPath).replace(/[()\s'"]/g, '\\$&');
 
       updatedContents ??= new MagicString(contents);
       // Always quote the URL to avoid potential downstream parsing problems

packages/angular/build/src/utils/path.ts

@@ -0,0 +1,37 @@
+/**
+ * @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 { posix } from 'node:path';
+import { platform } from 'node:process';
+
+const WINDOWS_PATH_SEPERATOR_REGEXP = /\\/g;
+
+/**
+ * Converts a Windows-style file path to a POSIX-compliant path.
+ *
+ * This function replaces all backslashes (`\`) with forward slashes (`/`).
+ * It is a no-op on POSIX systems (e.g., Linux, macOS), as the conversion
+ * only runs on Windows (`win32`).
+ *
+ * @param path - The file path to convert.
+ * @returns The POSIX-compliant file path.
+ *
+ * @example
+ * ```ts
+ * // On a Windows system:
+ * toPosixPath('C:\\Users\\Test\\file.txt');
+ * // => 'C:/Users/Test/file.txt'
+ *
+ * // On a POSIX system (Linux/macOS):
+ * toPosixPath('/home/user/file.txt');
+ * // => '/home/user/file.txt'
+ * ```
+ */
+export function toPosixPath(path: string): string {
+  return platform === 'win32' ? path.replace(WINDOWS_PATH_SEPERATOR_REGEXP, posix.sep) : path;
+}

packages/angular/build/src/utils/server-rendering/prerender.ts

@@ -13,6 +13,7 @@ import { OutputMode } from '../../builders/application/schema';
 import { BuildOutputFile, BuildOutputFileType } from '../../tools/esbuild/bundler-context';
 import { BuildOutputAsset } from '../../tools/esbuild/bundler-execution-result';
 import { assertIsError } from '../error';
+import { toPosixPath } from '../path';
 import { urlJoin } from '../url';
 import { WorkerPool } from '../worker-pool';
 import { IMPORT_EXEC_ARGV } from './esm-in-memory-loader/utils';
@@ -94,7 +95,7 @@ export async function prerenderPages(
 
   const assetsReversed: Record</** Destination */ string, /** Source */ string> = {};
   for (const { source, destination } of assets) {
-    assetsReversed[addLeadingSlash(destination.replace(/\\/g, posix.sep))] = source;
+    assetsReversed[addLeadingSlash(toPosixPath(destination))] = source;
   }
 
   // Get routes to prerender

packages/angular/build/src/utils/service-worker.ts

@@ -14,6 +14,7 @@ import { BuildOutputFile, BuildOutputFileType } from '../tools/esbuild/bundler-c
 import { BuildOutputAsset } from '../tools/esbuild/bundler-execution-result';
 import { assertIsError } from './error';
 import { loadEsmModule } from './load-esm';
+import { toPosixPath } from './path';
 
 class CliFilesystem implements Filesystem {
   constructor(
@@ -52,7 +53,7 @@ class CliFilesystem implements Filesystem {
 
       if (stats.isFile()) {
         // Uses posix paths since the service worker expects URLs
-        items.push('/' + path.relative(this.base, entryPath).replace(/\\/g, '/'));
+        items.push('/' + toPosixPath(path.relative(this.base, entryPath)));
       } else if (stats.isDirectory()) {
         subdirectories.push(entryPath);
       }
@@ -75,11 +76,11 @@ class ResultFilesystem implements Filesystem {
   ) {
     for (const file of outputFiles) {
       if (file.type === BuildOutputFileType.Media || file.type === BuildOutputFileType.Browser) {
-        this.fileReaders.set('/' + file.path.replace(/\\/g, '/'), async () => file.contents);
+        this.fileReaders.set('/' + toPosixPath(file.path), async () => file.contents);
       }
     }
     for (const file of assetFiles) {
-      this.fileReaders.set('/' + file.destination.replace(/\\/g, '/'), () =>
+      this.fileReaders.set('/' + toPosixPath(file.destination), () =>
         fsPromises.readFile(file.source),
       );
     }