Merge "Use mypy to do static type checking" into feature/zuulv3

test-requirements.txt

@@ -14,3 +14,4 @@ sphinxcontrib-programoutput
 oslosphinx
 mock
 PyMySQL
+mypy

tox.ini

@@ -27,8 +27,12 @@ deps = bindep
 commands = bindep test
 
 [testenv:pep8]
-# streamer is python3 only, so we need to run flake8 in python3
-commands = flake8 {posargs}
+# --ignore-missing-imports tells mypy to not try to follow imported modules
+# out of the current tree. As you might expect, we don't want to run static
+# type checking on the world - just on ourselves.
+commands =
+  flake8 {posargs}
+  mypy --ignore-missing-imports zuul
 
 [testenv:cover]
 commands =

zuul/driver/__init__.py

@@ -33,7 +33,7 @@ class Driver(object, metaclass=abc.ABCMeta):
     The class or instance attribute **name** must be provided as a string.
 
     """
-    name = None
+    name = None  # type: str
 
     def reconfigure(self, tenant):
         """Called when a tenant is reconfigured.

zuul/driver/bubblewrap/__init__.py

@@ -23,6 +23,8 @@ import shlex
 import subprocess
 import sys
 
+from typing import Dict, List  # flake8: noqa
+
 from zuul.driver import (Driver, WrapperInterface)
 
 
@@ -70,7 +72,7 @@ class BubblewrapDriver(Driver, WrapperInterface):
     name = 'bubblewrap'
     log = logging.getLogger("zuul.BubblewrapDriver")
 
-    mounts_map = {'rw': [], 'ro': []}
+    mounts_map = {'rw': [], 'ro': []}  # type: Dict[str, List]
 
     def __init__(self):
         self.bwrap_command = self._bwrap_command()

zuul/lib/yamlutil.py

@@ -13,7 +13,8 @@ import yaml
 from yaml import YAMLObject, YAMLError  # noqa: F401
 
 try:
-    from yaml import cyaml
+    # Explicit type ignore to deal with provisional import failure
+    from yaml import cyaml  # type: ignore
     import _yaml
     SafeLoader = cyaml.CSafeLoader
     SafeDumper = cyaml.CSafeDumper