chore(ui): do not watch output folders (#27694)

packages/playwright/src/runner/uiMode.ts

@@ -179,9 +179,12 @@ class UIMode {
     await reporter.onExit();
 
     const projectDirs = new Set<string>();
-    for (const p of this._config.projects)
+    const projectOutputs = new Set<string>();
+    for (const p of this._config.projects) {
       projectDirs.add(p.project.testDir);
-    this._globalWatcher.update([...projectDirs], false);
+      projectOutputs.add(p.project.outputDir);
+    }
+    this._globalWatcher.update([...projectDirs], [...projectOutputs], false);
   }
 
   private async _runTests(testIds: string[], projects: string[]) {
@@ -217,7 +220,7 @@ class UIMode {
       files.add(fileName);
       dependenciesForTestFile(fileName).forEach(file => files.add(file));
     }
-    this._testWatcher.update([...files], true);
+    this._testWatcher.update([...files], [], true);
   }
 
   private async _stopTests() {
@@ -259,6 +262,7 @@ type FSEvent = { event: 'add' | 'addDir' | 'change' | 'unlink' | 'unlinkDir', fi
 class Watcher {
   private _onChange: (events: FSEvent[]) => void;
   private _watchedFiles: string[] = [];
+  private _ignoredFolders: string[] = [];
   private _collector: FSEvent[] = [];
   private _fsWatcher: FSWatcher | undefined;
   private _throttleTimer: NodeJS.Timeout | undefined;
@@ -269,14 +273,15 @@ class Watcher {
     this._onChange = onChange;
   }
 
-  update(watchedFiles: string[], reportPending: boolean) {
+  update(watchedFiles: string[], ignoredFolders: string[], reportPending: boolean) {
-    if (JSON.stringify(this._watchedFiles) === JSON.stringify(watchedFiles))
+    if (JSON.stringify([this._watchedFiles, this._ignoredFolders]) === JSON.stringify(watchedFiles, ignoredFolders))
       return;
 
     if (reportPending)
       this._reportEventsIfAny();
 
     this._watchedFiles = watchedFiles;
+    this._ignoredFolders = ignoredFolders;
     void this._fsWatcher?.close();
     this._fsWatcher = undefined;
     this._collector.length = 0;
@@ -286,7 +291,7 @@ class Watcher {
     if (!this._watchedFiles.length)
       return;
 
-    this._fsWatcher = chokidar.watch(watchedFiles, { ignoreInitial: true }).on('all', async (event, file) => {
+    this._fsWatcher = chokidar.watch(watchedFiles, { ignoreInitial: true, ignored: this._ignoredFolders }).on('all', async (event, file) => {
       if (this._throttleTimer)
         clearTimeout(this._throttleTimer);
       if (this._mode === 'flat' && event !== 'add' && event !== 'change')

packages/trace-viewer/src/ui/uiModeView.tsx

@@ -103,7 +103,11 @@ export const UIModeView: React.FC<{}> = ({
     inputRef.current?.focus();
     setIsLoading(true);
     connect({ onEvent: dispatchEvent, onClose: () => setIsDisconnected(true) }).then(send => {
-      sendMessage = send;
+      sendMessage = async (method, params) => {
+        const logForTest = (window as any).__logForTest;
+        logForTest?.({ method, params });
+        await send(method, params);
+      };
       reloadTests();
     });
   }, [reloadTests]);

tests/playwright-test/ui-mode-test-watch.spec.ts

@@ -262,3 +262,30 @@ test('should queue watches', async ({ runUITest, writeFiles, createLatch }) => {
 
   await expect(page.getByTestId('status-line')).toHaveText('3/3 passed (100%)');
 });
+
+test('should not watch output', async ({ runUITest }) => {
+  const { page } = await runUITest({
+    'a.test.ts': `
+      import { test, expect } from '@playwright/test';
+      test('passes', ({}, testInfo) => {
+        require('fs').writeFileSync(testInfo.outputPath('output.txt'), 'DATA');
+      });
+    `,
+  });
+
+  await expect.poll(dumpTestTree(page)).toBe(`
+    ▼ ◯ a.test.ts
+        ◯ passes
+  `);
+
+  const commands: string[] = [];
+  await page.exposeBinding('__logForTest', (source, arg) => {
+    commands.push(arg.method);
+  });
+
+  await page.getByTitle('Run all').click();
+
+  await expect(page.getByTestId('status-line')).toHaveText('1/1 passed (100%)');
+  expect(commands).toContain('run');
+  expect(commands).not.toContain('list');
+});