refactor(@angular-devkit/build-angular): only use rename and change raw events

This commit updates the file watcher to only use rename and change events from raw events and will otherwise rely on all events to capture other file changes.

The rename and change events are watch are triggered when using IDEs that use atomic writes. This should improve cross-platform and cross IDE compatibility.

Author: alan-agius4

packages/angular_devkit/build_angular/src/tools/esbuild/watcher.ts

@@ -7,7 +7,7 @@
  */
 
 import { FSWatcher } from 'chokidar';
-import { normalize } from 'node:path';
+import { extname, normalize } from 'node:path';
 
 export class ChangedFiles {
   readonly added = new Set<string>();
@@ -98,55 +98,24 @@ export function createWatcher(options?: {
    * ... (Nothing)
    * ```
    */
-  watcher.on(watcher.options.useFsEvents ? 'all' : 'raw', (event, path, metadata) => {
-    switch (event) {
-      case 'add':
-      case 'change':
-      // When using Visual Studio the rename event is fired before a change event when the contents of the file changed
-      // or instead of `unlink` when the file has been renamed.
-      case 'unlink':
-      case 'rename':
-        // When polling is enabled `watchedPath` can be undefined.
-        // `path` is always normalized unlike `watchedPath`.
-        const changedPath = metadata?.watchedPath ? normalize(metadata.watchedPath) : path;
-        currentEvents ??= new Map();
-        currentEvents.set(changedPath, event);
-        break;
-      default:
+  watcher
+    .on('raw', (event, path, { watchedPath }) => {
+      if (watchedPath && !extname(watchedPath)) {
+        // Ignore directories, file changes in directories will be fired seperatly.
         return;
-    }
-
-    // Wait 250ms from next change to better capture groups of file save operations.
-    if (!nextWaitTimeout) {
-      nextWaitTimeout = setTimeout(() => {
-        nextWaitTimeout = undefined;
-        const next = nextQueue.shift();
-        if (next && currentEvents) {
-          const events = currentEvents;
-          currentEvents = undefined;
-
-          const currentChanges = new ChangedFiles();
-          for (const [path, event] of events) {
-            switch (event) {
-              case 'add':
-                currentChanges.added.add(path);
-                break;
-              case 'change':
-                currentChanges.modified.add(path);
-                break;
-              case 'unlink':
-              case 'rename':
-                currentChanges.removed.add(path);
-                break;
-            }
-          }
+      }
 
-          next(currentChanges);
-        }
-      }, 250);
-      nextWaitTimeout?.unref();
-    }
-  });
+      switch (event) {
+        case 'rename':
+        case 'change':
+          // When polling is enabled `watchedPath` can be undefined.
+          // `path` is always normalized unlike `watchedPath`.
+          const changedPath = watchedPath ? normalize(watchedPath) : path;
+          handleFileChange(event, changedPath);
+          break;
+      }
+    })
+    .on('all', handleFileChange);
 
   return {
     [Symbol.asyncIterator]() {
@@ -188,4 +157,51 @@ export function createWatcher(options?: {
       }
     },
   };
+
+  function handleFileChange(event: string, path: string): void {
+    switch (event) {
+      case 'add':
+      case 'change':
+      // When using Visual Studio the rename event is fired before a change event when the contents of the file changed
+      // or instead of `unlink` when the file has been renamed.
+      case 'unlink':
+      case 'rename':
+        currentEvents ??= new Map();
+        currentEvents.set(path, event);
+        break;
+      default:
+        return;
+    }
+
+    // Wait 250ms from next change to better capture groups of file save operations.
+    if (!nextWaitTimeout) {
+      nextWaitTimeout = setTimeout(() => {
+        nextWaitTimeout = undefined;
+        const next = nextQueue.shift();
+        if (next && currentEvents) {
+          const events = currentEvents;
+          currentEvents = undefined;
+
+          const currentChanges = new ChangedFiles();
+          for (const [path, event] of events) {
+            switch (event) {
+              case 'add':
+                currentChanges.added.add(path);
+                break;
+              case 'change':
+                currentChanges.modified.add(path);
+                break;
+              case 'unlink':
+              case 'rename':
+                currentChanges.removed.add(path);
+                break;
+            }
+          }
+
+          next(currentChanges);
+        }
+      }, 250);
+      nextWaitTimeout?.unref();
+    }
+  }
 }