import sys
import warnings
from contextlib import contextmanager
from typing import Generator
import pytest
from _pytest.main import Session
[docs]def _setoption(wmod, arg):
"""
Copy of the warning._setoption function but does not escape arguments.
"""
parts = arg.split(":")
if len(parts) > 5:
raise wmod._OptionError("too many fields (max 5): {!r}".format(arg))
while len(parts) < 5:
parts.append("")
action, message, category, module, lineno = [s.strip() for s in parts]
action = wmod._getaction(action)
category = wmod._getcategory(category)
if lineno:
try:
lineno = int(lineno)
if lineno < 0:
raise ValueError
except (ValueError, OverflowError):
raise wmod._OptionError("invalid lineno {!r}".format(lineno))
else:
lineno = 0
wmod.filterwarnings(action, message, category, module, lineno)
[docs]def pytest_addoption(parser):
group = parser.getgroup("pytest-warnings")
group.addoption(
"-W",
"--pythonwarnings",
action="append",
help="set which warnings to report, see -W option of python itself.",
)
parser.addini(
"filterwarnings",
type="linelist",
help="Each line specifies a pattern for "
"warnings.filterwarnings. "
"Processed after -W/--pythonwarnings.",
)
[docs]@contextmanager
def catch_warnings_for_item(config, ihook, when, item):
"""
Context manager that catches warnings generated in the contained execution block.
``item`` can be None if we are not in the context of an item execution.
Each warning captured triggers the ``pytest_warning_captured`` hook.
"""
cmdline_filters = config.getoption("pythonwarnings") or []
inifilters = config.getini("filterwarnings")
with warnings.catch_warnings(record=True) as log:
# mypy can't infer that record=True means log is not None; help it.
assert log is not None
if not sys.warnoptions:
# if user is not explicitly configuring warning filters, show deprecation warnings by default (#2908)
warnings.filterwarnings("always", category=DeprecationWarning)
warnings.filterwarnings("always", category=PendingDeprecationWarning)
# filters should have this precedence: mark, cmdline options, ini
# filters should be applied in the inverse order of precedence
for arg in inifilters:
_setoption(warnings, arg)
for arg in cmdline_filters:
warnings._setoption(arg)
if item is not None:
for mark in item.iter_markers(name="filterwarnings"):
for arg in mark.args:
_setoption(warnings, arg)
yield
for warning_message in log:
ihook.pytest_warning_captured.call_historic(
kwargs=dict(warning_message=warning_message, when=when, item=item)
)
[docs]@pytest.hookimpl(hookwrapper=True, tryfirst=True)
def pytest_runtest_protocol(item):
with catch_warnings_for_item(
config=item.config, ihook=item.ihook, when="runtest", item=item
):
yield
[docs]@pytest.hookimpl(hookwrapper=True, tryfirst=True)
def pytest_collection(session: Session) -> Generator[None, None, None]:
config = session.config
with catch_warnings_for_item(
config=config, ihook=config.hook, when="collect", item=None
):
yield
[docs]@pytest.hookimpl(hookwrapper=True)
def pytest_terminal_summary(terminalreporter):
config = terminalreporter.config
with catch_warnings_for_item(
config=config, ihook=config.hook, when="config", item=None
):
yield
[docs]@pytest.hookimpl(hookwrapper=True)
def pytest_sessionfinish(session):
config = session.config
with catch_warnings_for_item(
config=config, ihook=config.hook, when="config", item=None
):
yield
[docs]def _issue_warning_captured(warning, hook, stacklevel):
"""
This function should be used instead of calling ``warnings.warn`` directly when we are in the "configure" stage:
at this point the actual options might not have been set, so we manually trigger the pytest_warning_captured
hook so we can display these warnings in the terminal. This is a hack until we can sort out #2891.
:param warning: the warning instance.
:param hook: the hook caller
:param stacklevel: stacklevel forwarded to warnings.warn
"""
with warnings.catch_warnings(record=True) as records:
warnings.simplefilter("always", type(warning))
warnings.warn(warning, stacklevel=stacklevel)
# Mypy can't infer that record=True means records is not None; help it.
assert records is not None
frame = sys._getframe(stacklevel - 1)
location = frame.f_code.co_filename, frame.f_lineno, frame.f_code.co_name
hook.pytest_warning_captured.call_historic(
kwargs=dict(
warning_message=records[0], when="config", item=None, location=location
)
)