Repository navigation
Relax union math logic to allow signatures with different arg kinds - #5222
Merged
Merged
Conversation
Resolves python#5204. This commit relaxes the union math logic so that it allows signatures with arg kinds that are nearly identical except that one arg is positional and the other is optional. This commit also removes the "names must be the same" restriction mostly so that the original example given in python#4576 will pass. (In retrospect, I think this check didn't really buy us much -- even if the alternatives share the same arg names, there's no guarantee the actual implementation signature will also share the same.)
ilevkivskyi
approved these changes
Jun 15, 2018
ilevkivskyi
left a comment
ilevkivskyi
left a comment
Member
There was a problem hiding this comment.
Thanks! Looks good. Feel free to merge after addressing the comments.
| reveal_type(f(A())) # E: Revealed type is '__main__.B' | ||
| reveal_type(f(B())) # E: Revealed type is '__main__.C' | ||
| f(x) # E: Argument 1 to "f" has incompatible type "Union[A, B]"; expected "A" | ||
| reveal_type(f(x)) # E: Revealed type is 'Union[__main__.B, __main__.C]' |
Member
There was a problem hiding this comment.
The test case name should be updated (remove "Skip").
|
|
||
| x: Union[A, B] | ||
| f(x) # E: Argument 1 to "f" has incompatible type "Union[A, B]"; expected "A" | ||
| f(x, B()) # E: Argument 1 to "f" has incompatible type "Union[A, B]"; expected "B" |
Member
There was a problem hiding this comment.
I think ideally we could support something like this. Could you please add a TODO here? (I see you have a TODO in code, but I would prefer to have them both).
Collaborator
Author
|
Thanks! Merging now. |
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
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.
Resolves #5204.
This commit relaxes the union math logic so that it allows signatures with arg kinds that are nearly identical except that one arg is positional and the other is optional.
This commit also removes the "names must be the same" restriction mostly so that the original example given in #4576 will pass. (In retrospect, I think this check didn't really buy us much -- even if the alternatives share the same arg names, there's no guarantee the actual implementation signature will also share the same.)