add timeout to async playwright (#152)

* move async playwright start to a separate thread

* add changeset

* event loop is blocked - fixing

* revert

* update comment

* linter

* fix linter

* update

* formatting

* add changeset

* update

* update test

* Delete .changeset/wealthy-lion-of-honeydew.md

Author: filip-michalsky

.changeset/wakeful-pogona-of-stamina.md

@@ -0,0 +1,5 @@
+---
+"stagehand": patch
+---
+
+simple event loop timeout for strict event loops for async playwright (which has blocking start)

stagehand/main.py

@@ -391,7 +391,10 @@ async def init(self):
         self.logger.debug("Initializing Stagehand...")
         self.logger.debug(f"Environment: {self.env}")
 
-        self._playwright = await async_playwright().start()
+        # Initialize Playwright with timeout
+        self._playwright = await asyncio.wait_for(
+            async_playwright().start(), timeout=30.0  # 30 second timeout
+        )
 
         if self.env == "BROWSERBASE":
             # Create session if we don't have one

tests/unit/test_client_initialization.py

@@ -136,6 +136,31 @@ def test_init_as_context_manager(self):
         # Verify close is called in __aexit__
         assert client.close is not None
 
+    @pytest.mark.asyncio
+    async def test_init_playwright_timeout(self):
+        """Test that init() raises TimeoutError when playwright takes too long to start."""
+        config = StagehandConfig(env="LOCAL")
+        client = Stagehand(config=config)
+
+        # Mock async_playwright to simulate a hanging start() method
+        mock_playwright_instance = mock.AsyncMock()
+        mock_start = mock.AsyncMock()
+        
+        # Make start() hang indefinitely
+        async def hanging_start():
+            await asyncio.sleep(100)  # Sleep longer than the 30s timeout
+        
+        mock_start.side_effect = hanging_start
+        mock_playwright_instance.start = mock_start
+
+        with mock.patch("stagehand.main.async_playwright", return_value=mock_playwright_instance):
+            # The init() method should raise TimeoutError due to the 30-second timeout
+            with pytest.raises(asyncio.TimeoutError):
+                await client.init()
+
+        # Ensure the client is not marked as initialized
+        assert client._initialized is False
+
     @pytest.mark.asyncio
     async def test_create_session(self):
         """Test session creation."""