False positive for WPS345 Found meaningless number operation

[sobolevn]

Bug report

What's wrong

False positive for 1 / some:

  13:12    WPS345 Found meaningless number operation
  return 1 / number

How is that should be

1 / ANY should be allowed.

[serhii73]

Hello, @sobolevn. I can do it.
Can you tell me more about this task?
Because I do not fully understand when False-positive happen.
Thank you =)

[sobolevn]

@serhii73 here's the full explanation:

1. This code: https://github.com/wemake-services/wemake-python-styleguide/blob/master/wemake_python_styleguide/visitors/ast/operators.py#L98-L111 produces incorrect result. It treats 1 / some as useless math operation. But it is not. You can and should be able to use it.
2. These tests do not check it: https://github.com/wemake-services/wemake-python-styleguide/blob/master/tests/test_visitors/test_ast/test_operators/test_useless_math.py

Things we need to do:

1. Allow N / operations, they should be allowed for N != 0
2. Test these cases explicitly in a regression test

Thanks for your help! I appreciate that! 👍

[serhii73]

Thank you very much!
plz, assign this issue to me on the GitHub UI. Thank you =)

[serhii73]

Sorry @sobolevn can you help me?

@pytest.mark.parametrize('expression', [
........
])

I don't understand how to right write a list of expressions.

@pytest.mark.parametrize('expression', [
    '1 / other',
])

or

@pytest.mark.parametrize('expression', [
    '1 / 11',
])

it is not right.

[sobolevn]

@pytest.mark.parametrize('expression', [
    '1 / other',
    '1 / 11',
])

Are both correct according to this rule. But:

@pytest.mark.parametrize('expression', [
    'other / 1',
    '11 / 1',
])

Are not correct.