This gets imported from `_ast`, so the definition was
redundant. This causes problems with the new mypy semantic
analyzer, as it will flag the redefinition as an error.
This class is not defined at runtime but it's used by
mypy internally to support TypedDict methods.
Use NoReturn in argument types for better type safety
when the related mypy plugin hook is not active.
The change introduced in 395ab5abd1
broke the signature of `requests.post`, among others, since
`MutableSequence` is invariant, and plain `Dict[str, str]` values
were no longer valid for the `data` argument.
This changes the signature to have `Any` components as a
compromise. Adding more items to the union seems a bit too much, since
the error messages for invalid argument types are already pretty hard to
read.
Another option might be to use `Mapping` instead of `MutableMapping`
due to covariance, but I assume there's a reason why `MutableMapping`
is used here.
The previous definitions in `mock` caused many false positives in
internal Dropbox repositories.
One source of problems was `List[Mock]` not being compatible with
`List[SomeClass]`, since `list` is invariant.
Without this change, mypy can't infer proper types for cases like
`d.get(k, [])` where it needs type context to infer the type of
`[]`. We add the value type to the second argument to `get` using
union types, and this provides the context. This doesn't affect
the effective signature of `get`, other than providing the type
context for mypy.
Also removed some related redundant method definitions where we can
just inherit the base class definition. This makes it easier to
keep the method signatures consistent.
Note that this requires a few mypy PRs before mypy will be able to
use this effectively:
* https://github.com/python/mypy/pull/2718
* https://github.com/python/mypy/pull/2715
Jukka Lehtosalo