Update reviewboard.codesafety and reviewboard.registries for type hints.
Review Request #12782 — Created Jan. 11, 2023 and submitted
This enables type hints throughout
reviewboard.codesafety, and in
reviewboard.registriesto support typed registries. This ensures that
callers and implementations agree on types, which is important given
that dictionaries are often passed around.The change is a precursor to some upcoming work on code safety checkers
for custom Unicode confusable settings.
Unit tests pass on Python 3.7-3.11.