Repository navigation
bpo-46553: allow bare typing.ClassVar annotations - #30983
Merged
gvanrossum merged 3 commits intoJan 28, 2022
Merged
gvanrossum merged 3 commits into
gvanrossum merged 3 commits into
Conversation
Copy link
Copy Markdown
Contributor
Sorry, something went wrong.
These are used in the wild and covered by dataclasses unit tests. Several static type checkers support this pattern. Note we adjust one test from ClassVar[ClassVar] to ClassVar[ClassVar[int]] so that it still fails. This is surprising, but not a result of weirdness we're doing in this patch. This is a limitation of the current way runtime type checking works that this case is allowed when bare special forms are allowed. For example, before this patch `ClassVar[Final]` is a valid annotation despite nesting these forms being generally disallowed. Addressing this limitation could be future work.
GBeauregard
requested review from
Fidget-Spinner and
gvanrossum
as code owners
January 28, 2022 08:44
gvanrossum
approved these changes
Jan 28, 2022
Copy link
Copy Markdown
|
@gvanrossum: Please replace # with GH- in the commit message next time. Thanks! |
Sorry, something went wrong.
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Reviewers
4 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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
This is a simple matter of just adding ClassVar to the list of types allowed to be bare before the later call that raises for bare types.
These are used in the wild and covered by dataclasses unit tests.
Several static type checkers support this pattern.
Note we adjust one test from ClassVar[ClassVar] to
ClassVar[ClassVar[int]] so that it still fails. This is surprising, but
not a result of weirdness we're doing in this patch. This is a
limitation of the current way runtime type checking works that this case
is allowed when bare special forms are allowed. For example, before this
patch ClassVar[Final] is a valid runtime annotation despite nesting these
forms being generally disallowed, so it's expected allowing bare ClassVar
makes ClassVar[ClassVar] valid as well.
https://bugs.python.org/issue46553