Add missing type hints for retry.py

[max-muoto]

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Description of change

Add missing type hints for the retry.py module.

[gerzse]

Should AbstractBackoff be quoted here, when using if TYPE_CHECKING?

Tbh, it feels cleaner to just import AbstractBackoff always, it should not be a performance penalty.

[max-muoto]

You're right, went ahead and quoted it: 1660336

It would be nicer to quote, just to avoid an unnecessary import which would slow down module init time.

[gerzse]

We support Python 3.8, where this is not yet available. You can use Tuple[Type[Exception], ...] and import them from typing.

[max-muoto]

Ah yes, good catch!

[gerzse]

Same about supporting Python 3.8.

[max-muoto]

8df463b

[max-muoto]

@gerzse Comments should be addressed.

[gerzse]

@gerzse Comments should be addressed.

Thanks @max-muoto !

Getting picky now, but I run

mypy --python-version=3.8 redis/retry.py tests/test_retry.py tests/test_asyncio/test_retry.py

and it complains about BackoffMock class in the sync tests not being compatible with AbstractBackoff. Inheriting from AbstractBackoff, like in the async test should fix this.