p53209761
/
test_ok2
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Merge pull request #8260 from nicoddemus/faulthandler-mode-X-8258

This commit is contained in:
Bruno Oliveira 2021-01-28 13:03:24 -03:00 committed by GitHub
parent 7b4ee65bdc 33861098d9
commit 6a5d47a243
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 99 additions and 105 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
changelog/8258.bugfix.rst Normal file
View File

@ -0,0 +1,3 @@
Fixed issue where pytest's ``faulthandler`` support would not dump traceback on crashes
if the :mod:`faulthandler` module was already enabled during pytest startup (using
``python -X dev -m pytest`` for example).

135
src/_pytest/faulthandler.py
View File

@ -12,6 +12,7 @@ from _pytest.store import StoreKey
fault_handler_stderr_key = StoreKey[TextIO]()
fault_handler_originally_enabled_key = StoreKey[bool]()
def pytest_addoption(parser: Parser) -> None:
@ -25,92 +26,72 @@ def pytest_addoption(parser: Parser) -> None:
def pytest_configure(config: Config) -> None:
import faulthandler
if not faulthandler.is_enabled():
# faulthhandler is not enabled, so install plugin that does the actual work
# of enabling faulthandler before each test executes.
config.pluginmanager.register(FaultHandlerHooks(), "faulthandler-hooks")
else:
# Do not handle dumping to stderr if faulthandler is already enabled, so warn
# users that the option is being ignored.
timeout = FaultHandlerHooks.get_timeout_config_value(config)
if timeout > 0:
config.issue_config_time_warning(
pytest.PytestConfigWarning(
"faulthandler module enabled before pytest configuration step, "
"'faulthandler_timeout' option ignored"
),
stacklevel=2,
)
stderr_fd_copy = os.dup(get_stderr_fileno())
config._store[fault_handler_stderr_key] = open(stderr_fd_copy, "w")
config._store[fault_handler_originally_enabled_key] = faulthandler.is_enabled()
faulthandler.enable(file=config._store[fault_handler_stderr_key])
class FaultHandlerHooks:
"""Implements hooks that will actually install fault handler before tests execute,
as well as correctly handle pdb and internal errors."""
def pytest_unconfigure(config: Config) -> None:
import faulthandler
def pytest_configure(self, config: Config) -> None:
import faulthandler
stderr_fd_copy = os.dup(self._get_stderr_fileno())
config._store[fault_handler_stderr_key] = open(stderr_fd_copy, "w")
faulthandler.enable(file=config._store[fault_handler_stderr_key])
def pytest_unconfigure(self, config: Config) -> None:
import faulthandler
faulthandler.disable()
# close our dup file installed during pytest_configure
# re-enable the faulthandler, attaching it to the default sys.stderr
# so we can see crashes after pytest has finished, usually during
# garbage collection during interpreter shutdown
faulthandler.disable()
# Close the dup file installed during pytest_configure.
if fault_handler_stderr_key in config._store:
config._store[fault_handler_stderr_key].close()
del config._store[fault_handler_stderr_key]
faulthandler.enable(file=self._get_stderr_fileno())
if config._store.get(fault_handler_originally_enabled_key, False):
# Re-enable the faulthandler if it was originally enabled.
faulthandler.enable(file=get_stderr_fileno())
@staticmethod
def _get_stderr_fileno():
def get_stderr_fileno() -> int:
try:
fileno = sys.stderr.fileno()
# The Twisted Logger will return an invalid file descriptor since it is not backed
# by an FD. So, let's also forward this to the same code path as with pytest-xdist.
if fileno == -1:
raise AttributeError()
return fileno
except (AttributeError, io.UnsupportedOperation):
# pytest-xdist monkeypatches sys.stderr with an object that is not an actual file.
# https://docs.python.org/3/library/faulthandler.html#issue-with-file-descriptors
# This is potentially dangerous, but the best we can do.
return sys.__stderr__.fileno()
def get_timeout_config_value(config: Config) -> float:
return float(config.getini("faulthandler_timeout") or 0.0)
@pytest.hookimpl(hookwrapper=True, trylast=True)
def pytest_runtest_protocol(item: Item) -> Generator[None, None, None]:
timeout = get_timeout_config_value(item.config)
stderr = item.config._store[fault_handler_stderr_key]
if timeout > 0 and stderr is not None:
import faulthandler
faulthandler.dump_traceback_later(timeout, file=stderr)
try:
fileno = sys.stderr.fileno()
# The Twisted Logger will return an invalid file descriptor since it is not backed
# by an FD. So, let's also forward this to the same code path as with pytest-xdist.
if fileno == -1:
raise AttributeError()
return fileno
except (AttributeError, io.UnsupportedOperation):
# pytest-xdist monkeypatches sys.stderr with an object that is not an actual file.
# https://docs.python.org/3/library/faulthandler.html#issue-with-file-descriptors
# This is potentially dangerous, but the best we can do.
return sys.__stderr__.fileno()
@staticmethod
def get_timeout_config_value(config):
return float(config.getini("faulthandler_timeout") or 0.0)
@pytest.hookimpl(hookwrapper=True, trylast=True)
def pytest_runtest_protocol(self, item: Item) -> Generator[None, None, None]:
timeout = self.get_timeout_config_value(item.config)
stderr = item.config._store[fault_handler_stderr_key]
if timeout > 0 and stderr is not None:
import faulthandler
faulthandler.dump_traceback_later(timeout, file=stderr)
try:
yield
finally:
faulthandler.cancel_dump_traceback_later()
else:
yield
finally:
faulthandler.cancel_dump_traceback_later()
else:
yield
@pytest.hookimpl(tryfirst=True)
def pytest_enter_pdb(self) -> None:
"""Cancel any traceback dumping due to timeout before entering pdb."""
import faulthandler
faulthandler.cancel_dump_traceback_later()
@pytest.hookimpl(tryfirst=True)
def pytest_enter_pdb() -> None:
"""Cancel any traceback dumping due to timeout before entering pdb."""
import faulthandler
@pytest.hookimpl(tryfirst=True)
def pytest_exception_interact(self) -> None:
"""Cancel any traceback dumping due to an interactive exception being
raised."""
import faulthandler
faulthandler.cancel_dump_traceback_later()
faulthandler.cancel_dump_traceback_later()
@pytest.hookimpl(tryfirst=True)
def pytest_exception_interact() -> None:
"""Cancel any traceback dumping due to an interactive exception being
raised."""
import faulthandler
faulthandler.cancel_dump_traceback_later()

66
testing/test_faulthandler.py
View File

@ -19,22 +19,41 @@ def test_enabled(pytester: Pytester) -> None:
assert result.ret != 0
def test_crash_near_exit(pytester: Pytester) -> None:
"""Test that fault handler displays crashes that happen even after
pytest is exiting (for example, when the interpreter is shutting down)."""
def setup_crashing_test(pytester: Pytester) -> None:
pytester.makepyfile(
"""
import faulthandler
import atexit
def test_ok():
atexit.register(faulthandler._sigabrt)
"""
import faulthandler
import atexit
def test_ok():
atexit.register(faulthandler._sigabrt)
"""
)
result = pytester.runpytest_subprocess()
def test_crash_during_shutdown_captured(pytester: Pytester) -> None:
"""
Re-enable faulthandler if pytest encountered it enabled during configure.
We should be able to then see crashes during interpreter shutdown.
"""
setup_crashing_test(pytester)
args = (sys.executable, "-Xfaulthandler", "-mpytest")
result = pytester.run(*args)
result.stderr.fnmatch_lines(["*Fatal Python error*"])
assert result.ret != 0
def test_crash_during_shutdown_not_captured(pytester: Pytester) -> None:
"""
Check that pytest leaves faulthandler disabled if it was not enabled during configure.
This prevents us from seeing crashes during interpreter shutdown (see #8260).
"""
setup_crashing_test(pytester)
args = (sys.executable, "-mpytest")
result = pytester.run(*args)
result.stderr.no_fnmatch_line("*Fatal Python error*")
assert result.ret != 0
def test_disabled(pytester: Pytester) -> None:
"""Test option to disable fault handler in the command line."""
pytester.makepyfile(
@ -94,7 +113,7 @@ def test_cancel_timeout_on_hook(monkeypatch, hook_name) -> None:
to timeout before entering pdb (pytest-dev/pytest-faulthandler#12) or any
other interactive exception (pytest-dev/pytest-faulthandler#14)."""
import faulthandler
from _pytest.faulthandler import FaultHandlerHooks
from _pytest import faulthandler as faulthandler_plugin
called = []
@ -104,19 +123,18 @@ def test_cancel_timeout_on_hook(monkeypatch, hook_name) -> None:
# call our hook explicitly, we can trust that pytest will call the hook
# for us at the appropriate moment
hook_func = getattr(FaultHandlerHooks, hook_name)
hook_func(self=None)
hook_func = getattr(faulthandler_plugin, hook_name)
hook_func()
assert called == [1]
@pytest.mark.parametrize("faulthandler_timeout", [0, 2])
def test_already_initialized(faulthandler_timeout: int, pytester: Pytester) -> None:
"""Test for faulthandler being initialized earlier than pytest (#6575)."""
def test_already_initialized_crash(pytester: Pytester) -> None:
"""Even if faulthandler is already initialized, we still dump tracebacks on crashes (#8258)."""
pytester.makepyfile(
"""
def test():
import faulthandler
assert faulthandler.is_enabled()
faulthandler._sigabrt()
"""
)
result = pytester.run(
@ -125,22 +143,14 @@ def test_already_initialized(faulthandler_timeout: int, pytester: Pytester) -> N
"faulthandler",
"-mpytest",
pytester.path,
"-o",
f"faulthandler_timeout={faulthandler_timeout}",
)
# ensure warning is emitted if faulthandler_timeout is configured
warning_line = "*faulthandler.py*faulthandler module enabled before*"
if faulthandler_timeout > 0:
result.stdout.fnmatch_lines(warning_line)
else:
result.stdout.no_fnmatch_line(warning_line)
result.stdout.fnmatch_lines("*1 passed*")
assert result.ret == 0
result.stderr.fnmatch_lines(["*Fatal Python error*"])
assert result.ret != 0
def test_get_stderr_fileno_invalid_fd() -> None:
"""Test for faulthandler being able to handle invalid file descriptors for stderr (#8249)."""
from _pytest.faulthandler import FaultHandlerHooks
from _pytest.faulthandler import get_stderr_fileno
class StdErrWrapper(io.StringIO):
"""
@ -159,4 +169,4 @@ def test_get_stderr_fileno_invalid_fd() -> None:
# Even when the stderr wrapper signals an invalid file descriptor,
# ``_get_stderr_fileno()`` should return the real one.
assert FaultHandlerHooks._get_stderr_fileno() == 2
assert get_stderr_fileno() == 2