[ty] Support stringified annotations in value-position Annotated instances#21447
Merged
[ty] Support stringified annotations in value-position Annotated instances#21447
Annotated instances#21447Conversation
Diagnostic diff on typing conformance testsNo changes detected when running ty on typing conformance tests ✅ |
|
sharkdp
force-pushed
the
david/annotated-stringified
branch
from
8dcd2c8 to
37aaaca
Compare
sharkdp
requested review from
AlexWaygood,
carljm and
dcreager
as code owners
AlexWaygood
approved these changes
Nov 14, 2025
Comment on lines
+186
to
+195
| KnownInstanceType::Annotated(ty) => { | ||
| // Unions are not supported in this position, so we only need to support | ||
| // something like `class C(Annotated[Base, "metadata"]): ...`, which we | ||
| // can do by turning the instance type (`Base` in this example) back into | ||
| // a class. | ||
| let annotated_ty = ty.inner(db); | ||
| let instance_ty = annotated_ty.as_nominal_instance()?; | ||
|
|
||
| Some(Self::Class(instance_ty.class(db))) | ||
| } |
Member
There was a problem hiding this comment.
hmmmm I feel like there's probably going to be some edge case someone will come up with at some point where this lossy conversion will come back to bite us... but I'm not sure what they are, and this seems fine for now 😆
dcreager
added a commit
that referenced
this pull request
Nov 14, 2025
* origin/main: (59 commits) [ty] Improve diagnostic range for `non-subscriptable` diagnostics (#21461) [ty] Improve literal promotion heuristics (#21439) [ty] Further improve details around which expressions should be deferred in stub files (#21456) [ty] Improve generic class constructor inference (#21442) [ty] Propagate type context through conditional expressions (#21443) [ty] Suppress completions when introducing names with `as` [ty] Add panic-by-default await methods to `TestServer` (#21451) [ty] name is parameter and global is a syntax error (#21312) [ty] Fixup a few details around version-specific dataclass features (#21453) [ty] Support attribute-expression `TYPE_CHECKING` conditionals (#21449) [ty] Support stringified annotations in value-position `Annotated` instances (#21447) [ty] Type inference for genererator expressions (#21437) [ty] Make `__getattr__` available for `ModuleType` instances (#21450) [ty] Increase default receive timeout in tests to 10s (#21448) [ty] Add synthetic members to completions on dataclasses (#21446) [ty] Support legacy `typing` special forms in implicit type aliases (#21433) Bump 0.14.5 (#21435) [ty] Support `type[…]` and `Type[…]` in implicit type aliases (#21421) [ty] Respect notebook cell boundaries when adding an auto import (#21322) Update PyCharm setup instructions (#21409) ...
dcreager
added a commit
that referenced
this pull request
Nov 14, 2025
* dcreager/deep-comparison: (64 commits) assuming SubtypingAssuming implies_subtype_of name tweak Apply suggestions from code review [ty] Improve diagnostic range for `non-subscriptable` diagnostics (#21461) [ty] Improve literal promotion heuristics (#21439) [ty] Further improve details around which expressions should be deferred in stub files (#21456) [ty] Improve generic class constructor inference (#21442) [ty] Propagate type context through conditional expressions (#21443) [ty] Suppress completions when introducing names with `as` [ty] Add panic-by-default await methods to `TestServer` (#21451) [ty] name is parameter and global is a syntax error (#21312) [ty] Fixup a few details around version-specific dataclass features (#21453) [ty] Support attribute-expression `TYPE_CHECKING` conditionals (#21449) [ty] Support stringified annotations in value-position `Annotated` instances (#21447) [ty] Type inference for genererator expressions (#21437) [ty] Make `__getattr__` available for `ModuleType` instances (#21450) [ty] Increase default receive timeout in tests to 10s (#21448) [ty] Add synthetic members to completions on dataclasses (#21446) ...
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.
Summary
Infer the first argument
typeinsideAnnotated[type, …]as a type expression. This allows us to support stringified annotations insideAnnotated.Ecosystem
prefectshows that we now understand theState.datatype annotation insrc/prefect/client/schemas/objects.py:230, which uses a stringified annotation inAnnoated. The other diagnostics are downstream changes that result from this, it seems to be a commonly used data type.artigraphdoes something likeAnnotated[cast(Any, field_info.annotation), *field_info.metadata]which I'm not sure we need to allow? It's unfortunate since this is probably supported at runtime, but it seems reasonable that they need to add a# type: ignorefor that.pydanticuses something likeAnnotated[(self.annotation, *self.metadata)]but adds a# type: ignoreTest Plan
New Markdown test