Externalize flake8 linting, introduce additional checks

.travis.yml

@@ -5,7 +5,8 @@ python:
   - "3.4"
   # Specifically request 3.5.1 because we need to be compatible with that.
   - "3.5.1"
-  - "3.6-dev"
+  - "3.6"
+  - "3.7-dev"
   # Pypy build is disabled because it doubles the travis build time, and it rarely fails
   # unless one one of the other builds fails.
   # - "pypy3"
@@ -15,4 +16,5 @@ install:
   - python setup.py install
 
 script:
-  - python runtests.py
+  - python runtests.py -x lint
+  - if [[ $TRAVIS_PYTHON_VERSION == '3.6' ]]; then flake8; fi

extensions/mypy_extensions.py

@@ -22,9 +22,11 @@ def _check_fails(cls, other):
         pass
     return False
 
+
 def _dict_new(cls, *args, **kwargs):
     return dict(*args, **kwargs)
 
+
 def _typeddict_new(cls, _typename, _fields=None, **kwargs):
     if _fields is None:
         _fields = kwargs
@@ -33,6 +35,7 @@ def _typeddict_new(cls, _typename, _fields=None, **kwargs):
                         " but not both")
     return _TypedDictMeta(_typename, (), {'__annotations__': dict(_fields)})
 
+
 class _TypedDictMeta(type):
     def __new__(cls, name, bases, ns):
         # Create new typed dict class object.

runtests.py

@@ -151,11 +151,11 @@ def add_python2(self, name: str, *args: str, cwd: Optional[str] = None) -> None:
         env = self.env
         self.waiter.add(LazySubprocess(name, largs, cwd=cwd, env=env))
 
-    def add_flake8(self, name: str, file: str, cwd: Optional[str] = None) -> None:
-        name = 'lint %s' % name
+    def add_flake8(self, cwd: Optional[str] = None) -> None:
+        name = 'lint'
         if not self.allow(name):
             return
-        largs = ['flake8', file]
+        largs = ['flake8', '-j{}'.format(self.waiter.limit)]
         env = self.env
         self.waiter.add(LazySubprocess(name, largs, cwd=cwd, env=env))
 
@@ -167,13 +167,9 @@ def list_tasks(self) -> None:
 def add_basic(driver: Driver) -> None:
     if False:
         driver.add_mypy('file setup.py', 'setup.py')
-    driver.add_flake8('file setup.py', 'setup.py')
     driver.add_mypy('file runtests.py', 'runtests.py')
-    driver.add_flake8('file runtests.py', 'runtests.py')
     driver.add_mypy('legacy entry script', 'scripts/mypy')
-    driver.add_flake8('legacy entry script', 'scripts/mypy')
     driver.add_mypy('legacy myunit script', 'scripts/myunit')
-    driver.add_flake8('legacy myunit script', 'scripts/myunit')
     # needs typed_ast installed:
     driver.add_mypy('fast-parse', '--fast-parse', 'test-data/samples/hello.py')
 
@@ -206,7 +202,6 @@ def add_imports(driver: Driver) -> None:
         mod = file_to_module(f)
         if not mod.endswith('.__main__'):
             driver.add_python_string('import %s' % mod, 'import %s' % mod)
-        driver.add_flake8('module %s' % mod, f)
 
 
 PYTEST_FILES = ['mypy/test/{}.py'.format(name) for name in [
@@ -411,6 +406,7 @@ def main() -> None:
     add_stubs(driver)
     add_stdlibsamples(driver)
     add_samples(driver)
+    driver.add_flake8()
 
     if list_only:
         driver.list_tasks()

setup.cfg

@@ -1,7 +1,24 @@
 [flake8]
 max-line-length = 99
-exclude = mypy/codec/*
-# Thing to ignore:
+# typeshed and unit test fixtures have .pyi-specific flake8 configuration
+exclude =
+  # Sphinx configuration is irrelevant
+  docs/source/conf.py,
+  # external library with incompatible style
+  lib-typing/*,
+  # conflicting styles
+  misc/*,
+  # external library with incompatible style
+  pinfer/*,
+  # conflicting styles
+  scripts/*,
+  # tests have more relaxed styling requirements
+  # fixtures have their own .pyi-specific configuration
+  test-data/*,
+  # typeshed has its own .pyi-specific configuration
+  typeshed/*
+
+# Things to ignore:
 #   E251: spaces around default arg value (against our style)
 #   E128: continuation line under-indented (too noisy)
 #   F401: unused identifiers (useless, as it doesn't see inside # type: comments)
@@ -10,8 +27,10 @@ exclude = mypy/codec/*
 #   W503: line break before binary operator
 #   E704: multiple statements on one line (def)
 #   E402: module level import not at top of file
-#   B???: flake8-bugbear errors
-ignore = E251,E128,F401,W601,E701,W503,E704,E402,B
+#   B3??: Python 3 compatibility warnings
+#   B006: use of mutable defaults in function signatures
+#   B007: Loop control variable not used within the loop body.
+ignore = E251,E128,F401,W601,E701,W503,E704,E402,B3,B006,B007
 
 [coverage:run]
 branch = true

test-data/.flake8

@@ -0,0 +1 @@
+../typeshed/.flake8

test-requirements.txt

@@ -1,4 +1,6 @@
 flake8
+flake8-bugbear; python_version >= '3.5'
+flake8-pyi; python_version >= '3.5'
 lxml
 typed-ast>=0.6.1; sys_platform != 'win32'
 pytest>=2.8