Fix regression property no member 2641

[hippo91]

Steps

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Description

This PR adds the attr_fset method to the PropertModel class, so that pylint is able to deal with property setter.
The need for such a fix has been highlighted with #740 and is confirmed by the bug report pylint-dev/pylint#3480.

Type of Changes

	Type
✓	🐛 Bug fix

Related Issue

Closes pylint-dev/pylint#3480

[Pierre-Sassoulas]

Is this ready for merging ? If it fixes pylint's master I4m eager to have it merged 😄

[hippo91]

@Pierre-Sassoulas yes it is. I was just waiting for a review so now it is ok.
I got a day off tomorrow so i will try to merge it. I was also thinking about releasing a new astroid version (2.5?).
Are you ok with it?

[Pierre-Sassoulas]

Yeap, releasing astroid 2.5.0 seems like a good idea. Might be the time to use the new workflow with master becoming 2.6 and a creating a 2 .5 branch for bug fixes. I merged so I can fix pylint's master which I think will not work immediately :)

[Pierre-Sassoulas]

There are 5 pylint's unit tests not passing with latest astroid 2.5, that seems to work with astroid 2.4.1, I don't know how to fix, I suppose that was why you said "trying to merge" :) Sorry if I merged too prematurely.

[hippo91]

It is weird. I did not see any failing tests on my laptop. Where can i see those failing tests? Anyway i will look at this problem tomorrow.

[cdce8p]

I'm seeing them only with 3.9, 3.8 works fine. It's always an unused-import error, so probably not related to this MR.

FAILED tests/test_functional.py::test_functional[unsubscriptable_value] - AssertionError: Wrong results for file "unsubscriptable_value": FAILED tests/test_functional.py::test_functional[unpacking_non_sequence] - AssertionError: Wrong results for file "unpacking_non_sequence": FAILED tests/test_functional.py::test_functional[unsupported_delete_operation] - AssertionError: Wrong results for file "unsupported_delete_... FAILED tests/test_functional.py::test_functional[unsupported_assignment_operation] - AssertionError: Wrong results for file "unsupported_ass... FAILED tests/test_functional.py::test_functional[invalid_exceptions_caught] - AssertionError: Wrong results for file "invalid_exceptions_cau... 

Run with

pytest tests/test_functional.py 

--

Edit: Noticed that I had an old astroid version installed in my 3.8 environment. Error is version independent.
I used the following to install the current astroid commit:

pip uninstall astroid pip install -U git+git://github.com/PyCQA/astroid.git@0d8ed3f88deef0b2e85b5310b82cc3998220dc3c 

[cdce8p]

After some more investigation the issue first appeared after #841 was merged.
Looks like the pylint tests just need to be updated, though I know to little about it to be sure.

[Pierre-Sassoulas]

This MR's pipelines were launched after #890 got merged: (@cdce8p is right but there is also full traceback)

[hippo91]

@Pierre-Sassoulas @cdce8p thanks for your investigations.
I can confirm that #841 is the PR that triggers those failing tests. Those tests are the ones that are using six.with_metaclass (cf #841). So maybe there is a problem with this PR.
However, there is the pylint-dev/pylint#4006 that is here to remove six dependency. If we remove the six dependency on the failing unit tests modules then those ones are not failing anymore. I do not yet understand what is the criteria that @dgilman used to drop or keep six import in the unittests.
To conclude we are facing two possibilities: fixing a probable pb with #841 or totally drop the import of six module in pylint...