ruff/crates/ty_python_semantic/resources
David Peter 0761ea42d9
[ty] Eagerly evaluate `types.UnionType` elements as type expressions (#21531)
## Summary

Eagerly evaluate the elements of a PEP 604 union in value position (e.g.
`IntOrStr = int | str`) as type expressions and store the result (the
corresponding `Type::Union` if all elements are valid type expressions,
or the first encountered `InvalidTypeExpressionError`) on the
`UnionTypeInstance`, such that the `Type::Union(…)` does not need to be
recomputed every time the implicit type alias is used in a type
annotation.

This might lead to performance improvements for large unions, but is
also necessary for correctness, because the elements of the union might
refer to type variables that need to be looked up in the scope of the
type alias, not at the usage site.

## Test Plan

New Markdown tests
2025-11-20 17:28:48 +01:00
..
corpus [ty] fix global symbol lookup from eager scopes (#21317) 2025-11-12 10:15:51 -08:00
mdtest [ty] Eagerly evaluate `types.UnionType` elements as type expressions (#21531) 2025-11-20 17:28:48 +01:00
primer [ty] Add cycle handling to `lazy_default` (#20967) 2025-10-23 10:05:08 +02:00
README.md Rename Red Knot (#17820) 2025-05-03 19:49:15 +02:00

README.md

Markdown files within the mdtest/ subdirectory are tests of type inference and type checking; executed by the tests/mdtest.rs integration test.

See crates/ty_test/README.md for documentation of this test format.