Ensure asyncio blocking checks are undone after tests run (#119542)

* Ensure asyncio blocking checks are undone after tests run

* no reason to ever enable twice

* we are patching objects, make it more generic

* make sure bootstrap unblocks as well

* move disable to tests only

* re-protect

* Update tests/test_block_async_io.py

Co-authored-by: Erik Montnemery <erik@montnemery.com>

* Revert "Update tests/test_block_async_io.py"

This reverts commit 2d46028e21b4095479302629a201c3cfc811b2c2.

* tweak name

* fixture only

* Update tests/conftest.py

* Update tests/conftest.py

* Apply suggestions from code review

---------

Co-authored-by: Erik Montnemery <erik@montnemery.com>

homeassistant/block_async_io.py

@@ -1,7 +1,9 @@
 """Block blocking calls being done in asyncio."""
 
 import builtins
+from collections.abc import Callable
 from contextlib import suppress
+from dataclasses import dataclass
 import glob
 from http.client import HTTPConnection
 import importlib
@@ -46,53 +48,131 @@ def _check_sleep_call_allowed(mapped_args: dict[str, Any]) -> bool:
     return False
 
 
+@dataclass(slots=True, frozen=True)
+class BlockingCall:
+    """Class to hold information about a blocking call."""
+
+    original_func: Callable
+    object: object
+    function: str
+    check_allowed: Callable[[dict[str, Any]], bool] | None
+    strict: bool
+    strict_core: bool
+    skip_for_tests: bool
+
+
+_BLOCKING_CALLS: tuple[BlockingCall, ...] = (
+    BlockingCall(
+        original_func=HTTPConnection.putrequest,
+        object=HTTPConnection,
+        function="putrequest",
+        check_allowed=None,
+        strict=True,
+        strict_core=True,
+        skip_for_tests=False,
+    ),
+    BlockingCall(
+        original_func=time.sleep,
+        object=time,
+        function="sleep",
+        check_allowed=_check_sleep_call_allowed,
+        strict=True,
+        strict_core=True,
+        skip_for_tests=False,
+    ),
+    BlockingCall(
+        original_func=glob.glob,
+        object=glob,
+        function="glob",
+        check_allowed=None,
+        strict=False,
+        strict_core=False,
+        skip_for_tests=False,
+    ),
+    BlockingCall(
+        original_func=glob.iglob,
+        object=glob,
+        function="iglob",
+        check_allowed=None,
+        strict=False,
+        strict_core=False,
+        skip_for_tests=False,
+    ),
+    BlockingCall(
+        original_func=os.walk,
+        object=os,
+        function="walk",
+        check_allowed=None,
+        strict=False,
+        strict_core=False,
+        skip_for_tests=False,
+    ),
+    BlockingCall(
+        original_func=os.listdir,
+        object=os,
+        function="listdir",
+        check_allowed=None,
+        strict=False,
+        strict_core=False,
+        skip_for_tests=True,
+    ),
+    BlockingCall(
+        original_func=os.scandir,
+        object=os,
+        function="scandir",
+        check_allowed=None,
+        strict=False,
+        strict_core=False,
+        skip_for_tests=True,
+    ),
+    BlockingCall(
+        original_func=builtins.open,
+        object=builtins,
+        function="open",
+        check_allowed=_check_file_allowed,
+        strict=False,
+        strict_core=False,
+        skip_for_tests=True,
+    ),
+    BlockingCall(
+        original_func=importlib.import_module,
+        object=importlib,
+        function="import_module",
+        check_allowed=_check_import_call_allowed,
+        strict=False,
+        strict_core=False,
+        skip_for_tests=True,
+    ),
+)
+
+
+@dataclass(slots=True)
+class BlockedCalls:
+    """Class to track which calls are blocked."""
+
+    calls: set[BlockingCall]
+
+
+_BLOCKED_CALLS = BlockedCalls(set())
+
+
 def enable() -> None:
     """Enable the detection of blocking calls in the event loop."""
+    calls = _BLOCKED_CALLS.calls
+    if calls:
+        raise RuntimeError("Blocking call detection is already enabled")
+
     loop_thread_id = threading.get_ident()
-    # Prevent urllib3 and requests doing I/O in event loop
+    for blocking_call in _BLOCKING_CALLS:
-    HTTPConnection.putrequest = protect_loop(  # type: ignore[method-assign]
+        if _IN_TESTS and blocking_call.skip_for_tests:
-        HTTPConnection.putrequest, loop_thread_id=loop_thread_id
+            continue
-    )
 
-    # Prevent sleeping in event loop.
+        protected_function = protect_loop(
-    time.sleep = protect_loop(
+            blocking_call.original_func,
-        time.sleep,
+            strict=blocking_call.strict,
-        check_allowed=_check_sleep_call_allowed,
+            strict_core=blocking_call.strict_core,
-        loop_thread_id=loop_thread_id,
+            check_allowed=blocking_call.check_allowed,
-    )
-
-    glob.glob = protect_loop(
-        glob.glob, strict_core=False, strict=False, loop_thread_id=loop_thread_id
-    )
-    glob.iglob = protect_loop(
-        glob.iglob, strict_core=False, strict=False, loop_thread_id=loop_thread_id
-    )
-    os.walk = protect_loop(
-        os.walk, strict_core=False, strict=False, loop_thread_id=loop_thread_id
-    )
-
-    if not _IN_TESTS:
-        # Prevent files being opened inside the event loop
-        os.listdir = protect_loop(  # type: ignore[assignment]
-            os.listdir, strict_core=False, strict=False, loop_thread_id=loop_thread_id
-        )
-        os.scandir = protect_loop(  # type: ignore[assignment]
-            os.scandir, strict_core=False, strict=False, loop_thread_id=loop_thread_id
-        )
-
-        builtins.open = protect_loop(  # type: ignore[assignment]
-            builtins.open,
-            strict_core=False,
-            strict=False,
-            check_allowed=_check_file_allowed,
-            loop_thread_id=loop_thread_id,
-        )
-        # unittest uses `importlib.import_module` to do mocking
-        # so we cannot protect it if we are running tests
-        importlib.import_module = protect_loop(
-            importlib.import_module,
-            strict_core=False,
-            strict=False,
-            check_allowed=_check_import_call_allowed,
             loop_thread_id=loop_thread_id,
         )
+        setattr(blocking_call.object, blocking_call.function, protected_function)
+        calls.add(blocking_call)

tests/conftest.py

@@ -35,6 +35,8 @@ import requests_mock
 from syrupy.assertion import SnapshotAssertion
 from typing_extensions import AsyncGenerator, Generator
 
+from homeassistant import block_async_io
+
 # Setup patching if dt_util time functions before any other Home Assistant imports
 from . import patch_time  # noqa: F401, isort:skip
 
@@ -1814,3 +1816,15 @@ def service_calls(hass: HomeAssistant) -> Generator[None, None, list[ServiceCall
 def snapshot(snapshot: SnapshotAssertion) -> SnapshotAssertion:
     """Return snapshot assertion fixture with the Home Assistant extension."""
     return snapshot.use_extension(HomeAssistantSnapshotExtension)
+
+
+@pytest.fixture
+def disable_block_async_io() -> Generator[Any, Any, None]:
+    """Fixture to disable the loop protection from block_async_io."""
+    yield
+    calls = block_async_io._BLOCKED_CALLS.calls
+    for blocking_call in calls:
+        setattr(
+            blocking_call.object, blocking_call.function, blocking_call.original_func
+        )
+    calls.clear()

tests/test_block_async_io.py

@@ -17,6 +17,11 @@ from homeassistant.core import HomeAssistant
 from .common import extract_stack_to_frame
 
 
+@pytest.fixture(autouse=True)
+def disable_block_async_io(disable_block_async_io):
+    """Disable the loop protection from block_async_io after each test."""
+
+
 async def test_protect_loop_debugger_sleep(caplog: pytest.LogCaptureFixture) -> None:
     """Test time.sleep injected by the debugger is not reported."""
     block_async_io.enable()
@@ -214,13 +219,25 @@ async def test_protect_loop_open(caplog: pytest.LogCaptureFixture) -> None:
 
 async def test_protect_open(caplog: pytest.LogCaptureFixture) -> None:
     """Test opening a file in the event loop logs."""
-    block_async_io.enable()
+    with patch.object(block_async_io, "_IN_TESTS", False):
+        block_async_io.enable()
     with contextlib.suppress(FileNotFoundError):
         open("/config/data_not_exist", encoding="utf8").close()
 
     assert "Detected blocking call to open with args" in caplog.text
 
 
+async def test_enable_multiple_times(caplog: pytest.LogCaptureFixture) -> None:
+    """Test trying to enable multiple times."""
+    with patch.object(block_async_io, "_IN_TESTS", False):
+        block_async_io.enable()
+
+    with pytest.raises(
+        RuntimeError, match="Blocking call detection is already enabled"
+    ):
+        block_async_io.enable()
+
+
 @pytest.mark.parametrize(
     "path",
     [
@@ -231,7 +248,8 @@ async def test_protect_open(caplog: pytest.LogCaptureFixture) -> None:
 )
 async def test_protect_open_path(path: Any, caplog: pytest.LogCaptureFixture) -> None:
     """Test opening a file by path in the event loop logs."""
-    block_async_io.enable()
+    with patch.object(block_async_io, "_IN_TESTS", False):
+        block_async_io.enable()
     with contextlib.suppress(FileNotFoundError):
         open(path, encoding="utf8").close()
 
@@ -242,7 +260,8 @@ async def test_protect_loop_glob(
     hass: HomeAssistant, caplog: pytest.LogCaptureFixture
 ) -> None:
     """Test glob calls in the loop are logged."""
-    block_async_io.enable()
+    with patch.object(block_async_io, "_IN_TESTS", False):
+        block_async_io.enable()
     glob.glob("/dev/null")
     assert "Detected blocking call to glob with args" in caplog.text
     caplog.clear()
@@ -254,7 +273,8 @@ async def test_protect_loop_iglob(
     hass: HomeAssistant, caplog: pytest.LogCaptureFixture
 ) -> None:
     """Test iglob calls in the loop are logged."""
-    block_async_io.enable()
+    with patch.object(block_async_io, "_IN_TESTS", False):
+        block_async_io.enable()
     glob.iglob("/dev/null")
     assert "Detected blocking call to iglob with args" in caplog.text
     caplog.clear()
@@ -266,7 +286,8 @@ async def test_protect_loop_scandir(
     hass: HomeAssistant, caplog: pytest.LogCaptureFixture
 ) -> None:
     """Test glob calls in the loop are logged."""
-    block_async_io.enable()
+    with patch.object(block_async_io, "_IN_TESTS", False):
+        block_async_io.enable()
     with contextlib.suppress(FileNotFoundError):
         os.scandir("/path/that/does/not/exists")
     assert "Detected blocking call to scandir with args" in caplog.text
@@ -280,7 +301,8 @@ async def test_protect_loop_listdir(
     hass: HomeAssistant, caplog: pytest.LogCaptureFixture
 ) -> None:
     """Test listdir calls in the loop are logged."""
-    block_async_io.enable()
+    with patch.object(block_async_io, "_IN_TESTS", False):
+        block_async_io.enable()
     with contextlib.suppress(FileNotFoundError):
         os.listdir("/path/that/does/not/exists")
     assert "Detected blocking call to listdir with args" in caplog.text
@@ -293,8 +315,9 @@ async def test_protect_loop_listdir(
 async def test_protect_loop_walk(
     hass: HomeAssistant, caplog: pytest.LogCaptureFixture
 ) -> None:
-    """Test glob calls in the loop are logged."""
+    """Test os.walk calls in the loop are logged."""
-    block_async_io.enable()
+    with patch.object(block_async_io, "_IN_TESTS", False):
+        block_async_io.enable()
     with contextlib.suppress(FileNotFoundError):
         os.walk("/path/that/does/not/exists")
     assert "Detected blocking call to walk with args" in caplog.text
@@ -302,3 +325,13 @@ async def test_protect_loop_walk(
     with contextlib.suppress(FileNotFoundError):
         await hass.async_add_executor_job(os.walk, "/path/that/does/not/exists")
     assert "Detected blocking call to walk with args" not in caplog.text
+
+
+async def test_open_calls_ignored_in_tests(caplog: pytest.LogCaptureFixture) -> None:
+    """Test opening a file in tests is ignored."""
+    assert block_async_io._IN_TESTS
+    block_async_io.enable()
+    with contextlib.suppress(FileNotFoundError):
+        open("/config/data_not_exist", encoding="utf8").close()
+
+    assert "Detected blocking call to open with args" not in caplog.text

tests/test_bootstrap.py

@@ -55,6 +55,11 @@ async def apply_stop_hass(stop_hass: None) -> None:
     """Make sure all hass are stopped."""
 
 
+@pytest.fixture(autouse=True)
+def disable_block_async_io(disable_block_async_io):
+    """Disable the loop protection from block_async_io after each test."""
+
+
 @pytest.fixture(scope="module", autouse=True)
 def mock_http_start_stop() -> Generator[None]:
     """Mock HTTP start and stop."""