2a478ce1b2
## Summary If two types are gradually-equivalent, that means they share the same set of possible materializations. There's no need to keep two such types in the same union or intersection; we should simplify them. Fixes https://github.com/astral-sh/ruff/issues/17465 The one downside here is that now we will simplify e.g. `Unknown | Todo(...)` to just `Unknown`, if `Unknown` was added to the union first. This is correct from a type perspective (they are equivalent types), but it can mean we lose visibility into part of the cause for the type inferring as unknown. I think this is OK, but if we think it's important to avoid this, I can add a special case to try to preserve `Todo` over `Unknown`, if we see them both in the same union or intersection. ## Test Plan Added and updated mdtests.
Markdown files within the mdtest/ subdirectory are tests of type inference and type checking;
executed by the tests/mdtest.rs integration test.
See crates/red_knot_test/README.md for documentation of this test format.