fix(@angular-devkit/build-angular): use all style language watch files in esbuild builder

A recent change to better support Tailwind CSS in watch mode unintentionally caused part
of the watch files list for stylesheets to be ignored when Tailwind and/or autoprefixer
were required to be executed. This resulted in rebuilds occurring but all stylesheet changes
were not fully propagated to the development server. This has now been corrected.

(cherry picked from commit 4cf83eb)

Author: clydin

packages/angular_devkit/build_angular/src/tools/esbuild/stylesheets/stylesheet-plugin-factory.ts

@@ -232,7 +232,7 @@ async function compileString(
   options: StylesheetPluginOptions,
 ): Promise<OnLoadResult> {
   try {
-    const result = await postcssProcessor.process(data, {
+    const postcssResult = await postcssProcessor.process(data, {
       from: filename,
       to: filename,
       map: options.sourcemap && {
@@ -241,11 +241,15 @@ async function compileString(
       },
     });
 
-    const rawWarnings = result.warnings();
-    let warnings;
+    const loadResult: OnLoadResult = {
+      contents: postcssResult.css,
+      loader: 'css',
+    };
+
+    const rawWarnings = postcssResult.warnings();
     if (rawWarnings.length > 0) {
       const lineMappings = new Map<string, string[] | null>();
-      warnings = rawWarnings.map((warning) => {
+      loadResult.warnings = rawWarnings.map((warning) => {
         const file = warning.node.source?.input.file;
         if (file === undefined) {
           return { text: warning.text };
@@ -269,28 +273,22 @@ async function compileString(
       });
     }
 
-    let watchFiles;
-    for (const resultMessage of result.messages) {
+    for (const resultMessage of postcssResult.messages) {
       if (resultMessage.type === 'dependency' && typeof resultMessage['file'] === 'string') {
-        watchFiles ??= [];
-        watchFiles.push(resultMessage['file']);
+        loadResult.watchFiles ??= [];
+        loadResult.watchFiles.push(resultMessage['file']);
       } else if (
         resultMessage.type === 'dir-dependency' &&
         typeof resultMessage['dir'] === 'string' &&
         typeof resultMessage['glob'] === 'string'
       ) {
-        watchFiles ??= [];
+        loadResult.watchFiles ??= [];
         const dependencies = await glob(resultMessage['glob'], { cwd: resultMessage['dir'] });
-        watchFiles.push(...dependencies);
+        loadResult.watchFiles.push(...dependencies);
       }
     }
 
-    return {
-      contents: result.css,
-      loader: 'css',
-      warnings,
-      watchFiles,
-    };
+    return loadResult;
   } catch (error) {
     postcss ??= (await import('postcss')).default;
     if (error instanceof postcss.CssSyntaxError) {

tests/legacy-cli/e2e/tests/basic/rebuild.ts

@@ -158,4 +158,19 @@ export default async function () {
       throw new Error('Expected component CSS to update.');
     }
   }
+
+  await Promise.all([
+    waitForAnyProcessOutputToMatch(validBundleRegEx),
+    writeMultipleFiles({
+      'src/styles.css': 'div { color: green; }',
+    }),
+  ]);
+
+  {
+    const response = await fetch(`http://localhost:${port}/styles.css`);
+    const body = await response.text();
+    if (!body.match(/color:\s?green/)) {
+      throw new Error('Expected component CSS to update.');
+    }
+  }
 }