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.
24dcc76495