New type inference: add support for upper bounds and values by ilevkivskyi · Pull Request #15813 · python/mypy (original) (raw)

This is a third PR in series following #15287 and #15754. This one is quite simple: I just add basic support for polymorphic inference involving type variables with upper bounds and values. A complete support would be quite complicated, and it will be a corner case to already rare situation. Finally, it is written in a way that is easy to tune in the future.

I also use this PR to add some unit tests for all three PRs so far, other two PRs only added integration tests (and I clean up existing unit tests as well).