PD005 erroneously flags arithmetic methods from other packages

[deppen8]

Describe the bug
PD005 is triggered when any module has a method named something like .add()

To Reproduce
I noticed this while using the tarfile module. The tarfile module has a method named .add()

Here is the snippet. Flake8 triggered PD005 on both of the tar.add() calls.

tar = tarfile.open(tar_filename, "w")
tar.add(other_filename)  # <-- triggers PD005
for filename in filenames:
    tar.add(filename)  # <-- triggers PD005
tar.close()

Expected behavior
I expect this to only be triggered when a method like .add() is called on a pandas object.

Additional context
I expect that this applies to the comparison operators too (PD006). Any fix for PD005 should also be made for PD006 too.

[wanaryytel]

This is also true for PD011 with .values(), e.g. Flask request object has an attribute values, too.

[deppen8]

Indeed. I should create a new Issue detailing this, but the problem is that many of our checks rely on the type of the object being a pandas object. This is a fundamental issue with static linting in Python because the AST doesn't know what type a thing is.

I am open to suggestions on how to get around this, but it will likely be a big job. For now, the undesirable workaround is to turn off checks that are particularly bothersome.

[wanaryytel]

A quick hack (that could be optional for example) would be to check if pandas is imported in the file. Sure, it won't work for a lot of cases, but for a lot of cases it also will work.

[deppen8]

A quick hack (that could be optional for example) would be to check if pandas is imported in the file. Sure, it won't work for a lot of cases, but for a lot of cases it also will work.

I have considered this. If you'd like to put in a PR that adds this, I'd be happy to take a look at it.

[gahjelle]

Regarding the case for PD011 - .values, one check could be for the parentheses. I get a lot of false positives because I'm using both pandas and dictionaries. Looping through the values of the dictionary with .values() triggers PD011.

I'm not really familiar with the AST, so I don't know if this is an easy check or not.

[daviddavo]

What about type hinting?

Mypy uses the typed-ast package, but this has been included on the ast on Python 3.8+

So, in python < 3.8 you can use typed-ast, and on python 3.8+ you can just use the ast

Using type hinting, this shouldn't be a false positive:

import pandas as pd

bl: UnixDateBuilder = UnixDateBuilder()
bl.sub(month=3).change(day=1, hour=0, minute=0, second=0)

You can get the type of something using typing.get_type_hints()

Example from towardsdatascience: https://towardsdatascience.com/python-type-hints-docstrings-7ec7f6d3416b

[simchuck]

Is it possible to collect any `pandas` DataFrame objects to an internal `dict` variable, then confirm the suspect object is in this `dict` before throwing the error code? I'm not familiar with the details of `flake8`, but I suspect it might require a hook from that end to make this work.

…

On Mon, Mar 21, 2022 at 1:37 AM David Davó ***@***.***> wrote: What about type hinting? Mypy uses the typed-ast <https://pypi.org/project/typed-ast/> package, but this has been included on the ast on Python 3.8+ So, in python < 3.8 you can use typed-ast, and on python 3.8+ you can just use the ast Using type hinting, this shouldn't be a false positive: import pandas as pd bl: UnixDateBuilder = UnixDateBuilder() bl.sub(month=3).change(day=1, hour=0, minute=0, second=0) You can get the type of something using typing.get_type_hints() Example from towardsdatascience: https://towardsdatascience.com/python-type-hints-docstrings-7ec7f6d3416b — Reply to this email directly, view it on GitHub <#74 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAO2YGSKVIKYFSSBXUXCKA3VBAYMRANCNFSM4IXGILGQ> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>