disallow untyped defs

setup.cfg

@@ -42,7 +42,7 @@ deps =
 commands =
     black --check --diff src tests
     flake8 src tests
-    mypy src tests
+    mypy --disallow-untyped-defs src tests
     pytest tests
 
 [flake8]

src/basicpy/__init__.py

@@ -1,2 +1,2 @@
-def main():
+def main() -> None:
     print("Hello World")

tests/test_basicpy.py

@@ -1,2 +1,2 @@
-def test_basicpy():
+def test_basicpy() -> None:
     pass