Add context manager stubs to AudioFile class #446
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Problem Type checkers (mypy, pyright) report "invalid-context-manager" errors when using AudioFile as a context manager because the AudioFile class stub doesn't have __enter__ and __exit__ methods defined, even though all subclasses (ReadableAudioFile, WriteableAudioFile) and the runtime implementation do support the context manager protocol. Solution Add __enter__ and __exit__ method stubs to the AudioFile base class. The __enter__ method returns Union[ReadableAudioFile, WriteableAudioFile] to match the existing __new__ overloads, allowing type checkers to understand that AudioFile instances are valid context managers. Result Type checkers will no longer report errors when using AudioFile as a context manager with `with AudioFile(...) as f:` syntax.
This comment was marked as outdated.
This comment was marked as outdated.
Sorry, something went wrong.
psobot
reviewed
Jan 5, 2026
| those classes below for documentation. | ||
| """ | ||
|
|
||
| def __enter__(self) -> typing.Union[ReadableAudioFile, WriteableAudioFile]: |
Member
There was a problem hiding this comment.
It looks like this may be tripping up Pyright, used in tests:
with pedalboard.io.AudioFile(stream, "w", 44100, 2, format=extension) as af: # type: ignore
af.write(cached_rand(1, 2))...this code now seems to make Pyright think that the af could be a ReadableAudioFile, which doesn't have a write method, so we get:
/home/runner/work/pedalboard/pedalboard/tests/test_io.py
/home/runner/work/pedalboard/pedalboard/tests/test_io.py:621:16 - error: Cannot access attribute "write" for class "ReadableAudioFile"
Attribute "write" is unknown (reportAttributeAccessIssue)
Collaborator
Author
There was a problem hiding this comment.
Hmm, yeah. I'm not sure how to make everybody happy.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Type checkers report "invalid-context-manager" errors when using AudioFile as a context manager because the
AudioFileclass stub doesn't have__enter__and__exit__methods defined, even though all subclasses (ReadableAudioFile,WriteableAudioFile) and the runtime implementation do support the context manager protocol.Add
__enter__and__exit__method stubs to the AudioFile base class. The__enter__method returnsUnion[ReadableAudioFile, WriteableAudioFile]to match the existing__new__overloads, allowing type checkers to understand thatAudioFileinstances are valid context managers.