Add type hint checking with mypy

[dstansby]

This is a starting point to work towards #443. It:

• Adds configuration to run mypy
• pre-commit-config.yaml to run the type checking using pre-commit.
• Fixes type checking errors so that running mypy at least passes on the current code base.

TODO:

• Unit tests and/or doctests in docstrings
• Tests pass locally
• Docstrings and API docs for any new/modified user-facing classes and functions
• Changes documented in docs/release.rst
• Docs build locally
• GitHub Actions CI passes
• Test coverage to 100% (Codecov passes)

[pep8speaks]

Hello @dstansby! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file numcodecs/compat.py:

Line 109:33: E261 at least two spaces before inline comment

• In the file numcodecs/lzma.py:

Line 9:44: E261 at least two spaces before inline comment

• In the file numcodecs/ndarray_like.py:

Line 4:47: E261 at least two spaces before inline comment

• In the file numcodecs/zfpy.py:

Line 8:25: E261 at least two spaces before inline comment

Comment last updated at 2024-05-07 11:58:59 UTC