4.2.1 regression: "assert path.isfile()" hit in python.py:602

[rouault]

My software uses pytest in Travis-CI and it has just caught up with the 4.2.1 release. On a target running under Wine, I now get (extract from https://travis-ci.com/OSGeo/gdal/jobs/177514628 )

=================================== ERRORS ====================================
___________________ ERROR collecting pyscripts/__init__.py ____________________
C:\Python27\lib\site-packages\_pytest\runner.py:226: in from_call
    result = func()
C:\Python27\lib\site-packages\_pytest\runner.py:289: in <lambda>
    call = CallInfo.from_call(lambda: list(collector.collect()), "collect")
C:\Python27\lib\site-packages\_pytest\python.py:650: in collect
    for x in self._collectfile(path):
C:\Python27\lib\site-packages\_pytest\python.py:602: in _collectfile
    assert path.isfile()
E   AssertionError

[rouault]

Actually this is also true for a pure Windows run on AppVeyor: https://ci.appveyor.com/project/OSGeo/gdal/builds/22342341/job/0vumo9br4uus7jpb

[nicoddemus]

Thanks for the report @rouault!

[nicoddemus]

Hmmm that assert was added in 913a2da, cc @blueyed

On a side note, we probably should ban plain assert messages in favor of more descriptive error messages

[blueyed]

Duplicate of #4782.

#4784 fixes it.

[blueyed]

@rouault
Can you debug why that assertion fails for you?
I was currently assuming it would be a dangling symlink.

[blueyed]

Also please test if #4784 fixes it for you.

[rouault]

Thanks for the quick response. Unfortunately testing your fix will be impractical while it has not reached pip.
The issue is for some reason Windows specific, as Linux tests pass.
The content of the directory that causes the assertion is
https://github.com/OSGeo/gdal/tree/master/autotest/pyscripts
So it has a "init.py" file of size zero. There is no symlink.

[nicoddemus]

Thanks @blueyed!

Unfortunately testing your fix will be impractical while it has not reached pip.

@rouault It seems you install pytest with exec { pip install -Ur requirements.txt }, in that case you just need to change the line in requirements.txt from pytest>=3.6.0,<=4.2.0 to git+https://github.com/blueyed/pytest@fix-4782.

[rouault]

Thanks for the hint ! OK, so I can confirm that fix-4782 solves my issues on Windows.

[blueyed]

@rouault
Thanks for the feedback.

I would still be interested in what triggers it though.
Note that path is not the __init__.py (from the error message) likely:

pytest/src/_pytest/python.py

Lines 626 to 633 in 8726be2

	this_path = self.fspath.dirpath()
	init_module = this_path.join("__init__.py")
	if init_module.check(file=1) and path_matches_patterns(
	init_module, self.config.getini("python_files")
	):
	yield Module(init_module, self)
	pkg_prefixes = set()
	for path in this_path.visit(rec=self._recurse, bf=True, sort=True):

[blueyed]

@rouault
How did you test it? If you cannot reproduce it locally, maybe we could use a branch without the fix, but display the actual path?

[blueyed]

@rouault
You could try the assert branch: #4790

[rouault]

How did you test it?

I updated my requirements.txt to git+https://github.com/blueyed/pytest@fix-4782 and pushed that to get a new AppVeyor run

You could try the assert branch: #4790

Will do