Micha Reiser a467e7c8d3 [red-knot] Case sensitive module resolver (#16521) ... ## Summary This PR implements the first part of https://github.com/astral-sh/ruff/discussions/16440. It ensures that Red Knot's module resolver is case sensitive on all systems. This PR combines a few approaches: 1. It uses `canonicalize` on non-case-sensitive systems to get the real casing of a path. This works for as long as no symlinks or mapped network drives (the windows `E:\` is mapped to `\\server\share` thingy). This is the same as what Pyright does 2. If 1. fails, fall back to recursively list the parent directory and test if the path's file name matches the casing exactly as listed in by list dir. This is the same approach as CPython takes in its module resolver. The main downside is that it requires more syscalls because, unlike CPython, we Red Knot needs to invalidate its caches if a file name gets renamed (CPython assumes that the folders are immutable). It's worth noting that the file watching test that I added that renames `lib.py` to `Lib.py` currently doesn't pass on case-insensitive systems. Making it pass requires some more involved changes to `Files`. I plan to work on this next. There's the argument that landing this PR on its own isn't worth it without this issue being addressed. I think it's still a good step in the right direction even when some of the details on how and where the path case sensitive comparison is implemented. ## Test plan I added multiple integration tests (including a failing one). I tested that the `case-sensitivity` detection works as expected on Windows, MacOS and Linux and that the fast-paths are taken accordingly.		2025-03-14 19:16:44 +00:00
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src	[red-knot] Case sensitive module resolver (#16521)	2025-03-14 19:16:44 +00:00
Cargo.toml	ruff_db: add a vector for configuring diagnostic output (#16118)	2025-02-12 14:38:05 +00:00