fix(@angular/build): deduplicate spurious chokidar polling change events

packages/angular/build/BUILD.bazel

@@ -291,7 +291,6 @@ jasmine_test(
     name = "application_integration_tests",
     size = "medium",
     data = [":application_integration_test_lib"],
-    flaky = True,
     shard_count = 25,
 )
 
@@ -303,7 +302,6 @@ jasmine_test(
         # Force IPv4 to resolve RBE resolution issues
         "NODE_OPTIONS": "--dns-result-order=ipv4first",
     },
-    flaky = True,
     shard_count = 10,
 )
 
@@ -316,15 +314,13 @@ jasmine_test(
         # or standardize to avoid complex configuration like this!
         "PUPPETEER_DOWNLOAD_PATH": "../../../node_modules/puppeteer/downloads",
     },
-    flaky = True,
     shard_count = 10,
 )
 
 jasmine_test(
     name = "unit-test_integration_tests",
     size = "medium",
     data = [":unit-test_integration_test_lib"],
-    flaky = True,
     shard_count = 5,
 )
 

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

@@ -752,6 +752,7 @@ async function createChokidarWatcher(
 ): Promise<BuildWatcher> {
   const chokidar = chokidarModule ?? (await import('chokidar'));
   const watchedFiles = new Set<string>();
+  const fileStats = new Map<string, { mtimeMs: number; size: number }>();
 
   let queue: WatcherQueue;
   if (options?.polling) {
@@ -811,16 +812,36 @@ async function createChokidarWatcher(
       return;
     }
 
-    if (type !== 'removed') {
-      const stat = fs.statSync(rawPath, { throwIfNoEntry: false });
-      // Ignore historical events from before watcher initialization, but allow a 1000 ms window
-      // to account for coarse filesystem timestamp resolution (e.g., ext4/overlayfs integer second
-      // mtime truncation on Linux) where files modified during startup may have truncated .000 ms mtimes.
-      if (stat && stat.mtimeMs < initTime - 1000) {
-        return;
-      }
+    if (type === 'removed') {
+      fileStats.delete(lookupKey);
+      queue.addChange(type, rawPath);
+
+      return;
+    }
+
+    const stat = fs.statSync(rawPath, { throwIfNoEntry: false });
+    if (!stat) {
+      return;
     }
 
+    // Ignore historical events from before watcher initialization, but allow a 1000 ms window
+    // to account for coarse filesystem timestamp resolution (e.g., ext4/overlayfs integer second
+    // mtime truncation on Linux) where files modified during startup may have truncated .000 ms mtimes.
+    if (stat.mtimeMs < initTime - 1000) {
+      return;
+    }
+
+    const previousStat = fileStats.get(lookupKey);
+    if (
+      type === 'modified' &&
+      previousStat &&
+      previousStat.mtimeMs === stat.mtimeMs &&
+      previousStat.size === stat.size
+    ) {
+      return;
+    }
+
+    fileStats.set(lookupKey, { mtimeMs: stat.mtimeMs, size: stat.size });
     queue.addChange(type, rawPath);
   };
 
@@ -833,8 +854,23 @@ async function createChokidarWatcher(
       return this;
     },
 
-    next() {
-      return queue.next();
+    async next() {
+      const result = await queue.next();
+      if (result.value) {
+        const files = [...result.value.added, ...result.value.modified];
+        await Promise.all(
+          files.map(async (file) => {
+            const stat = await fs.promises.stat(file).catch(() => undefined);
+            if (stat?.isFile()) {
+              const posixPath = toPosixPathNormalized(file);
+              const lookupKey = toLookupKey(posixPath, isCaseSensitive);
+              fileStats.set(lookupKey, { mtimeMs: stat.mtimeMs, size: stat.size });
+            }
+          }),
+        );
+      }
+
+      return result;
     },
 
     add(paths) {
@@ -873,6 +909,7 @@ async function createChokidarWatcher(
         const lookupKey = toLookupKey(posixPath, isCaseSensitive);
         if (watchedFiles.has(lookupKey)) {
           watchedFiles.delete(lookupKey);
+          fileStats.delete(lookupKey);
 
           // When the last watched file in a package is removed, unwatch the package directory.
           const { isPackage, unwatchPkgDir } = nodeModulesManager.removePackageFile(