fix(android): reject pending callbacks on device close

[SebTardif]

Summary

• Reject all pending _callbacks when AndroidDevice._close() is called, preventing in-flight _send() calls from hanging forever
• Add a synchronous _isClosed guard after the await in _send() to prevent a race condition where _close() clears the callback map during the microtask yield

Problem

AndroidDevice._close() tears down the driver, backend, and browser connections, but never rejects the pending entries in _callbacks. Any in-flight _send() call that is awaiting a response when the device closes will hang indefinitely because its promise is never resolved or rejected.

All four browser protocol sessions (CR, FF, WK, Bidi) already handle this correctly:

// crConnection.ts:187-197
dispose() {
  this._closed = true;
  for (const callback of this._callbacks.values()) {
    callback.error.setMessage('Internal server error, session closed.');
    callback.reject(callback.error);
  }
  this._callbacks.clear();
}

The Android device uses the same callback map pattern (_callbacks: Map<number, { fulfill, reject }>) but was missing the cleanup loop.

Additionally, _send() has a race condition: it awaits this._driver() before checking _isClosed and adding to the callback map. A concurrent _close() can clear the map during that yield, leaving the new callback orphaned.

Related issues

• #21510: Android script gets stuck on context.newPage() / launchBrowser()
• #38424: webview.page() hangs forever on hidden/detached WebViews
• #35104: Android server stops unexpectedly before starting test
• #21049: launchBrowser() stuck on Oppo/Xiaomi devices
• #31474: Cancel inflight promises on page/context close

These issues all involve Android operations hanging or becoming unresponsive. While this fix does not address the root cause of each one (often device-specific firmware issues), it ensures that when the device does close, all pending operations fail cleanly instead of hanging the test process.

Comparable fix in Appium: appium/appium#6562 (hanging after clicking button that closes Android WebView, caused by pending callbacks not cleaned up).

Fix

1. In _close(): iterate _callbacks, reject each with Error('Device closed'), then clear the map. Placed before driver/backend teardown so callbacks are rejected while the transport is still valid.
2. In _send(): add this._isClosed check after await this._driver() to close the race window.

Changes

• packages/playwright-core/src/server/android/android.ts: 4 lines added

[github-actions]

Test results for "MCP"

5 failed
❌ [firefox] › mcp/annotate.spec.ts:137 › should abort MCP annotation when last screenshot is removed @mcp-windows-latest-firefox
❌ [firefox] › mcp/tracing.spec.ts:54 › check that trace is saved with browser_start_tracing (no output dir) @mcp-windows-latest-firefox
❌ [msedge] › mcp/cli-storage.spec.ts:61 › state-load restores storage state from file @mcp-windows-latest-msedge
❌ [msedge] › mcp/cli-storage.spec.ts:100 › state-save and state-load roundtrip @mcp-windows-latest-msedge
❌ [msedge] › mcp/test-run.spec.ts:126 › test_run should stop when aborted @mcp-windows-latest-msedge

7026 passed, 1068 skipped

---

Merge workflow run.

[github-actions]

Test results for "tests 1"

4 flaky

⚠️ [installation tests] › playwright-test-package-managers.spec.ts:38 › npm: @playwright/test + playwright-core should work `@package-installations-windows-latest`
⚠️ [chromium-library] › library/popup.spec.ts:261 › should not throw when click closes popup `@ubuntu-22.04-chromium-tip-of-tree`
⚠️ [chromium-library] › library/video.spec.ts:275 › screencast › should capture navigation `@chromium-ubuntu-22.04-node20`
⚠️ [chromium-library] › library/popup.spec.ts:261 › should not throw when click closes popup `@chromium-ubuntu-22.04-node22`

41692 passed, 850 skipped

---

Merge workflow run.