chore: add mypy type checking

.github/workflows/lint.yml

@@ -5,5 +5,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: chartboost/ruff-action@v1
-      - uses: psf/black@stable
+      - name: Setup Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: 3.11
+      - name: Install tox
+        run: pip install tox
+      - name: Lint with ruff, black and mypy
+        run: tox -e lint

.github/workflows/test.yml

@@ -1,8 +1,10 @@
 name: Python
-on: [push, pull_request]
+on: [pull_request]
 jobs:
   Pytest:
     runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python 3.10

git_hg_sync/__main__.py

@@ -1,5 +1,6 @@
 import argparse
 import sys
+import logging
 from pathlib import Path
 
 import sentry_sdk
@@ -45,7 +46,9 @@ def get_queue(config):
     )
 
 
-def start_app(config, logger, *, one_shot=False):
+def start_app(
+    config: Config, logger: logging.Logger, *, one_shot: bool = False
+) -> None:
     pulse_config = config.pulse
     connection = get_connection(pulse_config)
 

pyproject.toml

@@ -11,3 +11,11 @@ dependencies = ['kombu', 'mozillapulse', 'GitPython', 'mozlog', "pydantic", "sen
 
 [tool.ruff]
 line-length = 100
+
+[[tool.mypy.overrides]]
+module = [
+  'kombu.*',
+  'mozlog'
+]
+
+ignore_missing_imports = true

tests/utils.py

@@ -1,7 +1,8 @@
+from pathlib import Path
 import subprocess
 
 
-def hg_export_tip(repo_path: str):
+def hg_export_tip(repo_path: Path):
     process = subprocess.run(
         ["hg", "export", "tip"],
         cwd=repo_path,

tox.ini

@@ -19,6 +19,10 @@ description = lint source code
 deps =
     ruff
     black
+    mypy
+    pytest # dev dependency
+ignore_errors = true # Run commands even if an earlier command failed
 commands =
     ruff check git_hg_sync/ tests/
     black --check git_hg_sync tests
+    mypy git_hg_sync/ tests/