Bug Report

When usingmatch on a tuple of optionals, Mypy doesn't seem to:

1. Narrow the type fromOptional[T] toT in non-optional cases, even if all theNone cases have been handled.
2. Recognize that the match is exhaustive.

This feels similar to#12267 (comment), or maybe#12364 or#13989, but the example is a little different; apologies if it's a dupe / already known—and thanks for taking a look!

To Reproduce

https://mypy-play.net/?mypy=latest&python=3.11&gist=b6c10a27006d7b5ad55729467c2c5de8

Expected Behavior

No errors. 😊

I've used this match-on-a-tuple pattern inRust andSwift a few times, which is why I was a little surprised that Mypy didn't like it.

Actual Behavior

main.py:4: error: Missing return statement  [return]main.py:9: error: Item "None" of "Optional[str]" has no attribute "encode"  [union-attr]

Your Environment

• Mypy version used: 1.0.0
• Python version used: 3.11