Add mypy

dev-requirements.txt

@@ -1,4 +1,5 @@
 black==18.9b0
 flake8==3.6.0
 isort==4.3.4
+mypy==0.641
 nose2==0.8.0

scripts/test.sh

@@ -9,3 +9,4 @@ python setup.py test
 black tests ipc_unix --check
 flake8 ipc_unix tests --ignore=E128,E501
 isort -rc -c ipc_unix tests
+mypy --strict-optional ipc_unix tests

tests/__init__.py

@@ -8,7 +8,7 @@ class EchoServer(server.Server):
         return request
 
 
-def get_random_path():
+def get_random_path() -> str:
     _, temp_file_path = tempfile.mkstemp()
     os.remove(temp_file_path)
     return temp_file_path