## Summary
Two stable property tests are currently failing on `main`, following
f054b8a55e
(of course, I only thought to run the property tests again around 30
minutes _after_ landing that PR...). The issue is quite subtle, and took
me an annoying amount of time to pin down: we're matching over `(self,
other)` in `Type::is_disjoint_from_impl`, but `other` here is shadowed
by the binding in the `match` branch, which means that the wrong key is
inserted into the cache of the `IsDisjointFrom` cycle detector:
f054b8a55e/crates/ty_python_semantic/src/types.rs (L2408-L2435)
This PR fixes that issue, and also adds a few `Debug` implementations to
our cycle detectors, so that issues like this are easier to debug in the
future.
I'm adding the `internal` label, as this fixes a bug that hasn't yet
appeared in any released version of ty, so it doesn't deserve its own
changelog entry.
## Test Plan
`QUICKCHECK_TESTS=1000000 cargo test --release -p ty_python_semantic --
--ignored types::property_tests::stable` now once again passes on `main`
I considered adding new mdtests as well, but the examples that the
property tests were throwing at me all seemed _quite_ obscure and
somewhat unlikely to occur in the real world. I don't think it's worth
it.
b0c6217e0b