Version 0.15.0 aka python3.9

Features

• Adds python3.9 support
• Forbids to use new-style decorators on python3.9
• Changes how we treat own/foreign attributes,
  since now we only check assigned attribute names for self/cls/mcs,
  but not any other ones.
  So, now writting point.x = 1 will not trigger any violations.
  Previously, it would raise "too short name".
• Forbids using non-trivial expressions as an argument to except
• Forbids using too many variables in a tuple unpacking
• Forbids using float("NaN").
• Forbids assigning to a slice
• Allow __call__ method to be asynchronous
• Allows common strings not to be counted against string constant overuse limit
• Forbids to unpack iterable objects to lists #1259
• Forbids to use single return None
• Add __await__ to the list of priority magic methods
• Forbids to use float zeros (0.0)
• Forbids raise Exception and raise BaseException
• Forbids to use % with zero as the divisor
• WPS531: Forbids testing conditions to just return booleans when it is possible to simply return the condition itself
• Forbids to use unsafe infinite loops
• Forbids to use raw strings r'' when not necessary
• Forbids to use too complex f-strings
• Forbids to use too many raise statements inside a single function
• Forbids to compare with float and complex values
• Forbids single element destruct
• Forbids to ignore some violations (configurable) on a line level
• Forbids single element unpacking
• Forbids to unpack lists with side-effects
• Forbids to use miltiline strings except for assignments and docstrings
• Forbids not returning anything in functions and methods starting with get_
• Forbids to use empty comment
• Forbids using bitwise operation with boolean operation
• Forbids inconsistent structuring of multiline comprehensions
• Forbids to use unpythonic getters and setters such as get_attribute or set_attribute
• Now credits, license, and copyright builtins are free to shadow

Bugfixes

• Fixes fails of annotation complexity on Literal[""]
• Fixes how wrong variable names were checked case sensitive with WPS110
• Fixes false positives DirectMagicAttributeAccessViolation with __mro__, __subclasses__ and __version__
• Make WPS326 work when there is comment between string literals
• Allowed yield statements in call method
• Allow to use ^ with 1
• Fixes false positives in WPS513 and WPS323
• Fixes false positive WPS426 if lambda in loop uses only its arguments
• Fixes false negative WPS421 with pprint.pprint
• Fixes WPS441 triggering when reusing variable names in multiple loops
• Fixes false positive ImplicitEnumerateViolation on range with step #1742
• Allows to use _ to declare several unused variables,
  like: x, _, _ = coordinates()
• Fixes variable reassignment in class context
• Fixes that *'abc' was not counted as pointless star expression
• Fixes that -some was counted as overused expression
• Fixes several bugs with attribute names

Misc

• Updates lots of dependenices
• Fixed documentation for TooManyPublicAttributesViolation
• Updated isort config
• Introduce helper script to check for missing calls to self.generic_visit(node) in AST visitors
• Updates poetry version to 1.1
• Updates reviewdog version to 0.11.0 and adds action-depup