5ea3a52c8a
This makes one very simple change: we report all call binding errors from each union variant. This does result in duplicate-seeming diagnostics. For example, when two union variants are invalid for the same reason.
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.