Wemake-python-styleguide: Forbid too long call chains

[sobolevn]

Rule request

Thesis

In case you work with a really strange API that uses a lot of nested decorator functions (or with lots of partial application and curing) you can end up with something like this in your code base:

some(a)(b)(c)(d)

Well, that's not pythonic. This is a complexity rule to limit this kind of situations.

What do we need?

1. Option to regulate the complexity threshold, let's name it max_call_level
2. Default value should be 2, where 3 calls will result in a violation
3. A new complexity violation and a visitor

Related: https://github.com/wemake-services/wemake-python-styleguide/blob/8e759c1e80370234ac7bb30cf5f97fc953841688/wemake_python_styleguide/violations/complexity.py#L576
Related: #737 (where almost the same feature is implemented)

[lucaionescu]

Hi, can I be assigned to this issue?

[sobolevn]

@lucaionescu sure! Thanks a lot for your help!

[sobolevn]

Hi, @lucaionescu! How's it going? Do you need any help?

[lucaionescu]

Hey, thanks for checking in, it's all good for now! I was diving into the documentation and the contribution guide for the past days, just wanted to make sure I understand everything before I start to code.