[v2.3.0]

Added

• #87 Add --mypy-init-return to allow omission of a return type hint for __init__ if at least one argument is annotated.

Additional Details

To help provide compatibility with Mypy for maintainers that wish to do so, the --mypy-init-return flag has been introduced to mimic Mypy's allowance for the omission of return type hints for __init__ methods that are not dynamically typed (at least one argument is annotated). With this flag set, ANN200 level errors will be suppressed for __init__ methods if at least one argument is explicitly annotated.

For example, from Mypy's documentation:

class C1:  # Return annotated
    def __init__(self) -> None:
        self.var = 42

class C2:  # Return annotated
    def __init__(self, arg: int):
        self.var = arg

class C3:
    def __init__(self):  # Return not annotated
        # This body is not type checked
        self.var = 42 + 'abc'

NOTE: By default, Mypy does not enforce annotations for self in class methods, so to completely mimic Mypy's behavior with flake8-annotations ANN101 will need to be added to the repository's ignored linting codes.

See Mypy's documentation for additional details: https://mypy.readthedocs.io/en/stable/class_basics.html?#annotating-init-methods