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## Summary Fixes https://github.com/astral-sh/ruff/issues/15989 Red Knot failed to resolve relative imports if the importing module is located at a search path root. The issue was that the module resolver returned an `Err(TooManyDots)` as soon as the parent of the current module is `None` (which is the case for a module at the search path root). However, this is incorrect if a `tail` (a module name) exists.
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.