mypy insufficiently strict?

[fdmalone]

#1345 fixed a bug with PrepareIdentity being constructed with a tuple of QDTypes when it expects a Tuple of Registers. It's surprising mypy didn't catch this. The issue is to figure out why this was allowed.

[mpharrigan]

some reference docs: https://www.attrs.org/en/stable/types.html

could it be because sometimes the fields use field() and sometimes use type annotations?

[fdmalone]

maybe missing the "type" argument to field?