Previously, writing to sys.stdout/stderr in text-mode (e.g.
`print('foo')`) while a `capsysbinary` fixture is active, would crash
with:
/usr/lib/python3.7/contextlib.py:119: in __exit__
next(self.gen)
E TypeError: write() argument must be str, not bytes
This is due to some confusion in the types. The relevant functions are
`snap()` and `writeorg()`. The function `snap()` returns what was
captured, and the return type should be `bytes` for the binary captures
and `str` for the regular ones. The `snap()` return value is eventually
passed to `writeorg()` to be written to the original file, so it's input
type should correspond to `snap()`. But this was incorrect for
`SysCaptureBinary`, which handled it like `str`.
To fix this, be explicit in the `snap()` and `writeorg()`
implementations, also of the other Capture types.
We can't add type annotations yet, because the current inheritance
scheme breaks Liskov Substitution and mypy would complain. To be
refactored later.
Fixes: https://github.com/pytest-dev/pytest/issues/6871
Co-authored-by: Ran Benita (some modifications & commit message)
I tried to understand what the `safe_text_dupfile()` function and
`EncodedFile` class do. Outside tests, `EncodedFile` is only used by
`safe_text_dupfile`, and `safe_text_dupfile` is only used by
`FDCaptureBinary.__init__()`. I then started to eliminate always-true
conditions based on the single call site, and in the end nothing was
left except of a couple workarounds that are still needed.
The commit which added the checks for os.dup a15afb5e48
suggests it was done for Jython. But pytest doesn't support Jython
anymore (Jython is Python 2 only).
Furthermore, it looks like the faulthandler plugin (bundled in pytest
and enabled by default) uses os.dup() unprotected and there have not
been any complaints.
So seems better to just remove these checks, and only add if someone
with a legitimate use case complains.
This started from fixing the test, where `"xdist_strict True"` was used
as a single argument, although you typically would see `["xdist_strict",
"True"]`.
Improves the error message to mention the option that caused the error.
pytest has several instances where plugins set their own attributes on
objects they receive in hooks, like nodes and config. Since plugins are
detached from these object's definition by design, this causes a problem
for type checking because these attributes are not defined and mypy
complains.
Fix this by giving these objects a "store" which can be used by plugins
in a type-safe manner.
Currently this mechanism is private. We can consider exposing it at a
later point.
Passing in a tuple crashes in `_prepareconfig`:
def test_invoke_with_tuple(self):
> pytest.main(("-h",))
src/_pytest/config/__init__.py:82: in main
config = _prepareconfig(args, plugins)
src/_pytest/config/__init__.py:229: in _prepareconfig
return pluginmanager.hook.pytest_cmdline_parse(
…
src/_pytest/helpconfig.py:98: in pytest_cmdline_parse
config = outcome.get_result() # type: Config
src/_pytest/config/__init__.py:808: in pytest_cmdline_parse
self.parse(args)
src/_pytest/config/__init__.py:1017: in parse
self._preparse(args, addopts=addopts)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
def _preparse(self, args: List[str], addopts: bool = True) -> None:
…
if addopts:
ini_addopts = self.getini("addopts")
if ini_addopts:
> args[:] = self._validate_args(ini_addopts, "via addopts config") + args
E TypeError: can only concatenate list (not "tuple") to list
addopts = True
args = ('-h',)
env_addopts = ''
ini_addopts = ['-rfEX', …]
src/_pytest/config/__init__.py:956: TypeError: can only concatenate list (not "tuple") to list
Might be worth handling (converting it to a list for example), but it
was documented to be a list to begin with when removing support for
strings (a7e401656).
Mypy currently is unable to handle assigning attributes on function:
https://github.com/python/mypy/issues/2087.
pytest uses this for the outcome exceptions -- `pytest.fail.Exception`,
`pytest.exit.Exception` etc, and this is the canonical name by which they
are referred.
Initially we started working around this with type: ignores, and later
by switching e.g. `pytest.fail.Exception` with the direct exception
`Failed`. But this causes a lot of churn and is not as nice. And I also
found that some code relies on it, in skipping.py:
def pytest_configure(config):
if config.option.runxfail:
# yay a hack
import pytest
old = pytest.xfail
config._cleanup.append(lambda: setattr(pytest, "xfail", old))
def nop(*args, **kwargs):
pass
nop.Exception = xfail.Exception
setattr(pytest, "xfail", nop)
...
So it seems better to support it. Use a hack to make it work. The rest
of the commit rolls back all of the workarounds we added up to now.
`pytest.raises.Exception` also exists, but it's not used much so I kept
it as-is for now.
Hopefully in the future mypy supports this and this ugliness can be
removed.
Allows for filtering of PytestCacheWarning.
Using `_issue_warning_captured` is not necessary here, and was probably
only used because the cacheprovider misses warnings during
`pytest_sessionfinish`, which is also fixed here.
I think the usage of `_issue_warning_captured` can be removed/reduced
further, but also that this is good enough for now.
Ref: https://github.com/pytest-dev/pytest/issues/6681.
Ran Benita
Bruno Oliveira
Daniel Hahler
Ronny Pfannschmidt
Ronny Pfannschmidt