AttributeError: 'MypyStatusItem' object has no attribute 'collect' - running pytest 5.4 with looponfail

[offbyone]

I'm getting an error when running pytest 5.4 + pytest-xdist 1.22 + pytest-mypy 0.8.0:

metadata: {'Python': '3.6.13', 'Platform': '<redacted>', 'Packages': {'pytest': '5.4.3', 'py': '1.8.0', 'pluggy': '0.13.0'}, 'Plugins': {'html': '1.17.0', 'metadata': '1.7.0', 'mypy': '0.8.0', 'xdist': '1.22.2', 'forked': '0.2', 'cov': '2.4.0', 'hypothesis': '4.45.1'}}
hypothesis profile 'default' -> database=DirectoryBasedExampleDatabase('.hypothesis/examples')
rootdir: <redacted>, inifile: setup.cfg, testpaths: lib, test
plugins: html-1.17.0, metadata-1.7.0, mypy-0.8.0, xdist-1.22.2, forked-0.2, cov-2.4.0, hypothesis-4.45.1

When I make a change, causing the tests to re-run, I get this error:

lib/python3.6/site-packages/_pytest/runner.py:244: in from_call
    result = func()
lib/python3.6/site-packages/_pytest/runner.py:264: in <lambda>
    call = CallInfo.from_call(lambda: list(collector.collect()), "collect")
lib/python3.6/site-packages/_pytest/main.py:498: in collect
    yield from self._collect(fspath, parts)
lib/python3.6/site-packages/_pytest/main.py:581: in _collect
    yield next(m[0].collect())
E   AttributeError: 'MypyStatusItem' object has no attribute 'collect'

[dmtucker]

Thanks for the report 👍

SSCCE (pytest-5.4.3):

mkdir pkg
py="pkg/__init__.py"
echo 'foo: str = 5' > "$py"
venv/bin/pytest --mypy --looponfail "$py" &
echo > "$py"

From 6.0.0 through 6.1.2, it manifests a bit differently:

venv/lib/python3.8/site-packages/_pytest/runner.py:310: in from_call
    result = func()  # type: Optional[TResult]
venv/lib/python3.8/site-packages/_pytest/runner.py:340: in <lambda>
    call = CallInfo.from_call(lambda: list(collector.collect()), "collect")
venv/lib/python3.8/site-packages/_pytest/main.py:777: in collect
    assert isinstance(matching[0], nodes.Collector)
E   AssertionError

This appears to have been fixed in 6.2.0 by pytest-dev/pytest@66311ff#diff-689af6a98fad782f87c1473a3758c720d3e23ea0ecdc89617df250b2a093c6a8L778-R785

I also found pytest-dev/pytest#7763 which links to a plugin fix.