Fix scheduler race conditions and add comprehensive test suite (#9348)

tests/integration/test_scheduler_string_name_stress.py

@@ -0,0 +1,116 @@
+"""Stress test for heap scheduler with std::string names from multiple threads."""
+
+import asyncio
+from pathlib import Path
+import re
+
+from aioesphomeapi import UserService
+import pytest
+
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_scheduler_string_name_stress(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test that set_timeout/set_interval with std::string names doesn't crash when called from multiple threads."""
+
+    # Get the absolute path to the external components directory
+    external_components_path = str(
+        Path(__file__).parent / "fixtures" / "external_components"
+    )
+
+    # Replace the placeholder in the YAML config with the actual path
+    yaml_config = yaml_config.replace(
+        "EXTERNAL_COMPONENT_PATH", external_components_path
+    )
+
+    # Create a future to signal test completion
+    loop = asyncio.get_running_loop()
+    test_complete_future: asyncio.Future[None] = loop.create_future()
+
+    # Track executed callbacks and any crashes
+    executed_callbacks: set[int] = set()
+    error_messages: list[str] = []
+
+    def on_log_line(line: str) -> None:
+        # Check for crash indicators
+        if any(
+            indicator in line.lower()
+            for indicator in [
+                "segfault",
+                "abort",
+                "assertion",
+                "heap corruption",
+                "use after free",
+            ]
+        ):
+            error_messages.append(line)
+            if not test_complete_future.done():
+                test_complete_future.set_exception(Exception(f"Crash detected: {line}"))
+            return
+
+        # Track executed callbacks
+        match = re.search(r"Executed string-named callback (\d+)", line)
+        if match:
+            callback_id = int(match.group(1))
+            executed_callbacks.add(callback_id)
+
+        # Check for completion
+        if (
+            "String name stress test complete" in line
+            and not test_complete_future.done()
+        ):
+            test_complete_future.set_result(None)
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+        # Verify we can connect
+        device_info = await client.device_info()
+        assert device_info is not None
+        assert device_info.name == "sched-string-name-stress"
+
+        # List entities and services
+        _, services = await asyncio.wait_for(
+            client.list_entities_services(), timeout=5.0
+        )
+
+        # Find our test service
+        run_stress_test_service: UserService | None = None
+        for service in services:
+            if service.name == "run_string_name_stress_test":
+                run_stress_test_service = service
+                break
+
+        assert run_stress_test_service is not None, (
+            "run_string_name_stress_test service not found"
+        )
+
+        # Call the service to start the test
+        client.execute_service(run_stress_test_service, {})
+
+        # Wait for test to complete or crash
+        try:
+            await asyncio.wait_for(test_complete_future, timeout=30.0)
+        except asyncio.TimeoutError:
+            pytest.fail(
+                f"String name stress test timed out. Executed {len(executed_callbacks)} callbacks. "
+                f"This might indicate a deadlock."
+            )
+
+        # Verify no errors occurred (crashes already handled by exception)
+        assert not error_messages, f"Errors detected during test: {error_messages}"
+
+        # Verify we executed all 1000 callbacks (10 threads × 100 callbacks each)
+        assert len(executed_callbacks) == 1000, (
+            f"Expected 1000 callbacks but got {len(executed_callbacks)}"
+        )
+
+        # Verify each callback ID was executed exactly once
+        for i in range(1000):
+            assert i in executed_callbacks, f"Callback {i} was not executed"