Enable type checking

.pre-commit-config.yaml

@@ -58,6 +58,13 @@ repos:
       - id: check-useless-excludes
   - repo: local
     hooks:
+      - id: mypy
+        name: mypy
+        entry: tox -e mypy --
+        language: system
+        require_serial: true
+        exclude: (/conftest.py$|/test_.*\.py$)
+        types: [python]
       - id: pylint
         name: pylint
         entry: tox -e pylint --

pyproject.toml

@@ -26,6 +26,11 @@ exclude_lines = [
 known_first_party = "grizzly"
 profile = "black"
 
+[tool.mypy]
+ignore_missing_imports = true
+strict = true
+show_error_codes = true
+
 [tool.pylint.format]
 max-line-length = 88
 

tox.ini

@@ -37,6 +37,13 @@ deps =
     pre-commit
 skip_install = true
 
+[testenv:mypy]
+commands =
+    mypy --install-types --non-interactive {posargs}
+deps =
+    mypy==v1.10.0
+usedevelop = true
+
 [testenv:pylint]
 commands =
     pylint -j 0 {posargs}