feat(py): introduce mypy

template/py/{{cookiecutter.project_slug}}/Makefile

@@ -13,7 +13,7 @@ sync:
 
 # Build wheel
 build:
-	@uvx hatch build
+	@uv build
 
 # Test
 test:
@@ -28,6 +28,10 @@ ruff:
 	@uvx ruff format .
 	@uvx ruff check . --fix
 
+# Type check
+type:
+	@uvx mypy .
+
 # Build image
 image:
 	@docker image build -t $(APP_NAME) .

template/py/{{cookiecutter.project_slug}}/pyproject.toml

@@ -75,5 +75,26 @@ exclude_lines = [
 show_missing = true  # Show missing lines in the report
 precision = 2  # Number of decimal places to use when rounding
 
-# [tool.uv.pip]
-# index-url = "https://mirrors.cernet.edu.cn/pypi/web/simple"
+[tool.mypy]
+# Enable strict mode for comprehensive type checking
+strict = true
+python_version = "{{cookiecutter.python_version}}"
+
+# Error reporting settings
+pretty = true              # Beautify output for better readability
+show_error_codes = true    # Display error codes for easier troubleshooting
+show_error_context = true  # Show context for errors to aid debugging
+
+# Ignore missing type hints for third-party libraries
+ignore_missing_imports = true
+
+# Exclude specific paths or files from type checking
+exclude = [
+    "tests/",
+    "setup.py",
+]
+
+# Relax type-checking rules for test files (e.g., allow functions without type annotations)
+[[tool.mypy.overrides]]
+module = "tests.*"
+disallow_untyped_defs = false

template/py/{{cookiecutter.project_slug}}/src/{{cookiecutter.package_name}}/app.py

@@ -1,7 +1,7 @@
 from http.server import HTTPServer, SimpleHTTPRequestHandler
 
 
-def run_server(port=8000):
+def run_server(port: int = 8000) -> None:
     handler = SimpleHTTPRequestHandler
     with HTTPServer(("", port), handler) as httpd:
         print(f"Serving at port {port}")

template/py/{{cookiecutter.project_slug}}/src/{{cookiecutter.package_name}}/example.py

@@ -1,16 +1,16 @@
-def add(a, b):
+def add(a: int | float, b: int | float) -> int | float:
     return a + b
 
 
-def subtract(a, b):
+def subtract(a: int | float, b: int | float) -> int | float:
     return a - b
 
 
-def multiply(a, b):
+def multiply(a: int | float, b: int | float) -> int | float:
     return a * b
 
 
-def divide(a, b):
+def divide(a: int | float, b: int | float) -> int | float:
     if b == 0:
         raise ValueError("Division by zero is not allowed.")
     return a / b