297 lines
10 KiB
Python
297 lines
10 KiB
Python
|
"""Record warnings during test function execution."""
|
||
|
|
import re
|
||
|
|
import warnings
|
||
|
|
from types import TracebackType
|
||
|
|
from typing import Any
|
||
|
|
from typing import Callable
|
||
|
|
from typing import Generator
|
||
|
|
from typing import Iterator
|
||
|
|
from typing import List
|
||
|
|
from typing import Optional
|
||
|
|
from typing import overload
|
||
|
|
from typing import Pattern
|
||
|
|
from typing import Tuple
|
||
|
|
from typing import Type
|
||
|
|
from typing import TypeVar
|
||
|
|
from typing import Union
|
||
|
|
|
||
|
|
from _pytest.compat import final
|
||
|
|
from _pytest.deprecated import check_ispytest
|
||
|
|
from _pytest.fixtures import fixture
|
||
|
|
from _pytest.outcomes import fail
|
||
|
|
|
||
|
|
|
||
|
|
T = TypeVar("T")
|
||
|
|
|
||
|
|
|
||
|
|
@fixture
|
||
|
|
def recwarn() -> Generator["WarningsRecorder", None, None]:
|
||
|
|
"""Return a :class:`WarningsRecorder` instance that records all warnings emitted by test functions.
|
||
|
|
|
||
|
|
See http://docs.python.org/library/warnings.html for information
|
||
|
|
on warning categories.
|
||
|
|
"""
|
||
|
|
wrec = WarningsRecorder(_ispytest=True)
|
||
|
|
with wrec:
|
||
|
|
warnings.simplefilter("default")
|
||
|
|
yield wrec
|
||
|
|
|
||
|
|
|
||
|
|
@overload
|
||
|
|
def deprecated_call(
|
||
|
|
*, match: Optional[Union[str, Pattern[str]]] = ...
|
||
|
|
) -> "WarningsRecorder":
|
||
|
|
...
|
||
|
|
|
||
|
|
|
||
|
|
@overload
|
||
|
|
def deprecated_call(func: Callable[..., T], *args: Any, **kwargs: Any) -> T:
|
||
|
|
...
|
||
|
|
|
||
|
|
|
||
|
|
def deprecated_call(
|
||
|
|
func: Optional[Callable[..., Any]] = None, *args: Any, **kwargs: Any
|
||
|
|
) -> Union["WarningsRecorder", Any]:
|
||
|
|
"""Assert that code produces a ``DeprecationWarning`` or ``PendingDeprecationWarning``.
|
||
|
|
|
||
|
|
This function can be used as a context manager::
|
||
|
|
|
||
|
|
>>> import warnings
|
||
|
|
>>> def api_call_v2():
|
||
|
|
... warnings.warn('use v3 of this api', DeprecationWarning)
|
||
|
|
... return 200
|
||
|
|
|
||
|
|
>>> import pytest
|
||
|
|
>>> with pytest.deprecated_call():
|
||
|
|
... assert api_call_v2() == 200
|
||
|
|
|
||
|
|
It can also be used by passing a function and ``*args`` and ``**kwargs``,
|
||
|
|
in which case it will ensure calling ``func(*args, **kwargs)`` produces one of
|
||
|
|
the warnings types above. The return value is the return value of the function.
|
||
|
|
|
||
|
|
In the context manager form you may use the keyword argument ``match`` to assert
|
||
|
|
that the warning matches a text or regex.
|
||
|
|
|
||
|
|
The context manager produces a list of :class:`warnings.WarningMessage` objects,
|
||
|
|
one for each warning raised.
|
||
|
|
"""
|
||
|
|
__tracebackhide__ = True
|
||
|
|
if func is not None:
|
||
|
|
args = (func,) + args
|
||
|
|
return warns((DeprecationWarning, PendingDeprecationWarning), *args, **kwargs)
|
||
|
|
|
||
|
|
|
||
|
|
@overload
|
||
|
|
def warns(
|
||
|
|
expected_warning: Optional[Union[Type[Warning], Tuple[Type[Warning], ...]]],
|
||
|
|
*,
|
||
|
|
match: Optional[Union[str, Pattern[str]]] = ...,
|
||
|
|
) -> "WarningsChecker":
|
||
|
|
...
|
||
|
|
|
||
|
|
|
||
|
|
@overload
|
||
|
|
def warns(
|
||
|
|
expected_warning: Optional[Union[Type[Warning], Tuple[Type[Warning], ...]]],
|
||
|
|
func: Callable[..., T],
|
||
|
|
*args: Any,
|
||
|
|
**kwargs: Any,
|
||
|
|
) -> T:
|
||
|
|
...
|
||
|
|
|
||
|
|
|
||
|
|
def warns(
|
||
|
|
expected_warning: Optional[Union[Type[Warning], Tuple[Type[Warning], ...]]],
|
||
|
|
*args: Any,
|
||
|
|
match: Optional[Union[str, Pattern[str]]] = None,
|
||
|
|
**kwargs: Any,
|
||
|
|
) -> Union["WarningsChecker", Any]:
|
||
|
|
r"""Assert that code raises a particular class of warning.
|
||
|
|
|
||
|
|
Specifically, the parameter ``expected_warning`` can be a warning class or
|
||
|
|
sequence of warning classes, and the inside the ``with`` block must issue a warning of that class or
|
||
|
|
classes.
|
||
|
|
|
||
|
|
This helper produces a list of :class:`warnings.WarningMessage` objects,
|
||
|
|
one for each warning raised.
|
||
|
|
|
||
|
|
This function can be used as a context manager, or any of the other ways
|
||
|
|
:func:`pytest.raises` can be used::
|
||
|
|
|
||
|
|
>>> import pytest
|
||
|
|
>>> with pytest.warns(RuntimeWarning):
|
||
|
|
... warnings.warn("my warning", RuntimeWarning)
|
||
|
|
|
||
|
|
In the context manager form you may use the keyword argument ``match`` to assert
|
||
|
|
that the warning matches a text or regex::
|
||
|
|
|
||
|
|
>>> with pytest.warns(UserWarning, match='must be 0 or None'):
|
||
|
|
... warnings.warn("value must be 0 or None", UserWarning)
|
||
|
|
|
||
|
|
>>> with pytest.warns(UserWarning, match=r'must be \d+$'):
|
||
|
|
... warnings.warn("value must be 42", UserWarning)
|
||
|
|
|
||
|
|
>>> with pytest.warns(UserWarning, match=r'must be \d+$'):
|
||
|
|
... warnings.warn("this is not here", UserWarning)
|
||
|
|
Traceback (most recent call last):
|
||
|
|
...
|
||
|
|
Failed: DID NOT WARN. No warnings of type ...UserWarning... was emitted...
|
||
|
|
|
||
|
|
"""
|
||
|
|
__tracebackhide__ = True
|
||
|
|
if not args:
|
||
|
|
if kwargs:
|
||
|
|
msg = "Unexpected keyword arguments passed to pytest.warns: "
|
||
|
|
msg += ", ".join(sorted(kwargs))
|
||
|
|
msg += "\nUse context-manager form instead?"
|
||
|
|
raise TypeError(msg)
|
||
|
|
return WarningsChecker(expected_warning, match_expr=match, _ispytest=True)
|
||
|
|
else:
|
||
|
|
func = args[0]
|
||
|
|
if not callable(func):
|
||
|
|
raise TypeError(
|
||
|
|
"{!r} object (type: {}) must be callable".format(func, type(func))
|
||
|
|
)
|
||
|
|
with WarningsChecker(expected_warning, _ispytest=True):
|
||
|
|
return func(*args[1:], **kwargs)
|
||
|
|
|
||
|
|
|
||
|
|
class WarningsRecorder(warnings.catch_warnings):
|
||
|
|
"""A context manager to record raised warnings.
|
||
|
|
|
||
|
|
Adapted from `warnings.catch_warnings`.
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self, *, _ispytest: bool = False) -> None:
|
||
|
|
check_ispytest(_ispytest)
|
||
|
|
# Type ignored due to the way typeshed handles warnings.catch_warnings.
|
||
|
|
super().__init__(record=True) # type: ignore[call-arg]
|
||
|
|
self._entered = False
|
||
|
|
self._list: List[warnings.WarningMessage] = []
|
||
|
|
|
||
|
|
@property
|
||
|
|
def list(self) -> List["warnings.WarningMessage"]:
|
||
|
|
"""The list of recorded warnings."""
|
||
|
|
return self._list
|
||
|
|
|
||
|
|
def __getitem__(self, i: int) -> "warnings.WarningMessage":
|
||
|
|
"""Get a recorded warning by index."""
|
||
|
|
return self._list[i]
|
||
|
|
|
||
|
|
def __iter__(self) -> Iterator["warnings.WarningMessage"]:
|
||
|
|
"""Iterate through the recorded warnings."""
|
||
|
|
return iter(self._list)
|
||
|
|
|
||
|
|
def __len__(self) -> int:
|
||
|
|
"""The number of recorded warnings."""
|
||
|
|
return len(self._list)
|
||
|
|
|
||
|
|
def pop(self, cls: Type[Warning] = Warning) -> "warnings.WarningMessage":
|
||
|
|
"""Pop the first recorded warning, raise exception if not exists."""
|
||
|
|
for i, w in enumerate(self._list):
|
||
|
|
if issubclass(w.category, cls):
|
||
|
|
return self._list.pop(i)
|
||
|
|
__tracebackhide__ = True
|
||
|
|
raise AssertionError("%r not found in warning list" % cls)
|
||
|
|
|
||
|
|
def clear(self) -> None:
|
||
|
|
"""Clear the list of recorded warnings."""
|
||
|
|
self._list[:] = []
|
||
|
|
|
||
|
|
# Type ignored because it doesn't exactly warnings.catch_warnings.__enter__
|
||
|
|
# -- it returns a List but we only emulate one.
|
||
|
|
def __enter__(self) -> "WarningsRecorder": # type: ignore
|
||
|
|
if self._entered:
|
||
|
|
__tracebackhide__ = True
|
||
|
|
raise RuntimeError("Cannot enter %r twice" % self)
|
||
|
|
_list = super().__enter__()
|
||
|
|
# record=True means it's None.
|
||
|
|
assert _list is not None
|
||
|
|
self._list = _list
|
||
|
|
warnings.simplefilter("always")
|
||
|
|
return self
|
||
|
|
|
||
|
|
def __exit__(
|
||
|
|
self,
|
||
|
|
exc_type: Optional[Type[BaseException]],
|
||
|
|
exc_val: Optional[BaseException],
|
||
|
|
exc_tb: Optional[TracebackType],
|
||
|
|
) -> None:
|
||
|
|
if not self._entered:
|
||
|
|
__tracebackhide__ = True
|
||
|
|
raise RuntimeError("Cannot exit %r without entering first" % self)
|
||
|
|
|
||
|
|
super().__exit__(exc_type, exc_val, exc_tb)
|
||
|
|
|
||
|
|
# Built-in catch_warnings does not reset entered state so we do it
|
||
|
|
# manually here for this context manager to become reusable.
|
||
|
|
self._entered = False
|
||
|
|
|
||
|
|
|
||
|
|
@final
|
||
|
|
class WarningsChecker(WarningsRecorder):
|
||
|
|
def __init__(
|
||
|
|
self,
|
||
|
|
expected_warning: Optional[
|
||
|
|
Union[Type[Warning], Tuple[Type[Warning], ...]]
|
||
|
|
] = None,
|
||
|
|
match_expr: Optional[Union[str, Pattern[str]]] = None,
|
||
|
|
*,
|
||
|
|
_ispytest: bool = False,
|
||
|
|
) -> None:
|
||
|
|
check_ispytest(_ispytest)
|
||
|
|
super().__init__(_ispytest=True)
|
||
|
|
|
||
|
|
msg = "exceptions must be derived from Warning, not %s"
|
||
|
|
if expected_warning is None:
|
||
|
|
expected_warning_tup = None
|
||
|
|
elif isinstance(expected_warning, tuple):
|
||
|
|
for exc in expected_warning:
|
||
|
|
if not issubclass(exc, Warning):
|
||
|
|
raise TypeError(msg % type(exc))
|
||
|
|
expected_warning_tup = expected_warning
|
||
|
|
elif issubclass(expected_warning, Warning):
|
||
|
|
expected_warning_tup = (expected_warning,)
|
||
|
|
else:
|
||
|
|
raise TypeError(msg % type(expected_warning))
|
||
|
|
|
||
|
|
self.expected_warning = expected_warning_tup
|
||
|
|
self.match_expr = match_expr
|
||
|
|
|
||
|
|
def __exit__(
|
||
|
|
self,
|
||
|
|
exc_type: Optional[Type[BaseException]],
|
||
|
|
exc_val: Optional[BaseException],
|
||
|
|
exc_tb: Optional[TracebackType],
|
||
|
|
) -> None:
|
||
|
|
super().__exit__(exc_type, exc_val, exc_tb)
|
||
|
|
|
||
|
|
__tracebackhide__ = True
|
||
|
|
|
||
|
|
# only check if we're not currently handling an exception
|
||
|
|
if exc_type is None and exc_val is None and exc_tb is None:
|
||
|
|
if self.expected_warning is not None:
|
||
|
|
if not any(issubclass(r.category, self.expected_warning) for r in self):
|
||
|
|
__tracebackhide__ = True
|
||
|
|
fail(
|
||
|
|
"DID NOT WARN. No warnings of type {} was emitted. "
|
||
|
|
"The list of emitted warnings is: {}.".format(
|
||
|
|
self.expected_warning, [each.message for each in self]
|
||
|
|
)
|
||
|
|
)
|
||
|
|
elif self.match_expr is not None:
|
||
|
|
for r in self:
|
||
|
|
if issubclass(r.category, self.expected_warning):
|
||
|
|
if re.compile(self.match_expr).search(str(r.message)):
|
||
|
|
break
|
||
|
|
else:
|
||
|
|
fail(
|
||
|
|
"DID NOT WARN. No warnings of type {} matching"
|
||
|
|
" ('{}') was emitted. The list of emitted warnings"
|
||
|
|
" is: {}.".format(
|
||
|
|
self.expected_warning,
|
||
|
|
self.match_expr,
|
||
|
|
[each.message for each in self],
|
||
|
|
)
|
||
|
|
)
|