Fix python 3.7 -> 3.7-dev and add flake8 testing

Also fixed flake8 errors.

.travis.yml

@@ -1,13 +1,27 @@
 language: python
+cache: pip
 python:
  - '3.5'
  - '3.6'
- - '3.7'
+ - '3.7-dev'
+
+matrix:
+    fast_finish: true
+    include:
+      - python: "3.5"
+        env: TOXENV=flake8
+
+    allow_failures:
+      - env: TOXENV=flake8
+
 install:
  - pip install -r requirements_dev.txt
+
 before_script:
  - coverage erase
+
 script:
  - tox
+
 after_success:
- - coveralls
+ - coveralls

src/drf_swagger/codecs.py

@@ -55,7 +55,7 @@ class _OpenAPICodec(BaseCodec):
     def validators(self):
         return self._validators
 
-    def encode(self, document, **options):
+    def encode(self, document, **_):
         if not isinstance(document, openapi.Swagger):
             raise TypeError('Expected a `openapi.Swagger` instance')
 

src/drf_swagger/views.py

@@ -5,7 +5,7 @@ from django.utils.cache import add_never_cache_headers
 from django.utils.decorators import available_attrs
 from django.views.decorators.cache import cache_page
 from django.views.decorators.vary import vary_on_headers
-from rest_framework import exceptions, renderers
+from rest_framework import exceptions
 from rest_framework.response import Response
 from rest_framework.settings import api_settings
 from rest_framework.views import APIView
@@ -14,7 +14,6 @@ from .generators import OpenAPISchemaGenerator
 from .renderers import (
     SwaggerJSONRenderer, SwaggerYAMLRenderer, SwaggerUIRenderer, ReDocRenderer, OpenAPIRenderer,
 )
-from .openapi import Info
 
 SPEC_RENDERERS = (SwaggerYAMLRenderer, SwaggerJSONRenderer, OpenAPIRenderer)
 UI_RENDERERS = {
@@ -53,7 +52,7 @@ def get_schema_view(info, url=None, patterns=None, urlconf=None, *, public=False
     """
     Create a SchemaView class with default renderers and generators.
 
-    :param Info info: Required. Swagger API Info object
+    :param drf_swagger.openapi.Info info: Required. Swagger API Info object
     :param str url: API base url; if left blank will be deduced from the location the view is served at
     :param str patterns: passed to SchemaGenerator
     :param str urlconf: passed to SchemaGenerator

testproj/manage.py

@@ -11,7 +11,7 @@ if __name__ == "__main__":
         # issue is really that Django is missing to avoid masking other
         # exceptions on Python 2.
         try:
-            import django
+            import django  # noqa: F401
         except ImportError:
             raise ImportError(
                 "Couldn't import Django. Are you sure it's installed and "

testproj/snippets/admin.py

@@ -1,3 +1 @@
-from django.contrib import admin
-
 # Register your models here.

testproj/snippets/serializers.py

@@ -1,6 +1,5 @@
-from rest_framework.status import HTTP_400_BAD_REQUEST
-
 from rest_framework import serializers
+
 from snippets.models import Snippet, LANGUAGE_CHOICES, STYLE_CHOICES
 
 

testproj/testproj/runner.py

@@ -1,9 +1,10 @@
 import os
 
+
 class PytestTestRunner(object):
     """Runs pytest to discover and run tests."""
 
-    def __init__(self, verbosity=1, failfast=False, keepdb=False, **kwargs):
+    def __init__(self, verbosity=1, failfast=False, keepdb=False, **_):
         self.verbosity = verbosity
         self.failfast = failfast
         self.keepdb = keepdb

testproj/testproj/settings.py

@@ -1,7 +1,5 @@
 import os
 
-import sys
-
 # Build paths inside the project like this: os.path.join(BASE_DIR, ...)
 BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 

testproj/testproj/urls.py

@@ -25,5 +25,5 @@ urlpatterns = [
     url(r'^redoc/$', schema_view.with_ui('redoc', cache_timeout=None), name='schema-redoc'),
 
     url(r'^admin/', admin.site.urls),
-    url(f'^snippets/', include('snippets.urls')),
+    url(r'^snippets/', include('snippets.urls')),
 ]

tests/conftest.py

@@ -1,8 +1,7 @@
 import pytest
-from ruamel import yaml
-
 from drf_swagger import openapi, codecs
 from drf_swagger.generators import OpenAPISchemaGenerator
+from ruamel import yaml
 
 
 @pytest.fixture

tests/test_schema_generator.py

@@ -1,11 +1,9 @@
 import json
 
-from ruamel import yaml
+import pytest
-
 from drf_swagger import openapi, codecs
 from drf_swagger.generators import OpenAPISchemaGenerator
-
+from ruamel import yaml
-import pytest
 
 
 def validate_schema(swagger):
@@ -14,8 +12,8 @@ def validate_schema(swagger):
 
     validate_flex(swagger)
     validate_ssv(swagger)
-    
+
-    
+
 def test_schema_generates_without_errors(generator):
     generator.get_schema(None, True)
 

tox.ini

@@ -1,5 +1,6 @@
 [tox]
-envlist = py35,py36,py37
+envlist = py35,py36,py37,flake8
+
 [testenv]
 deps=
     -rrequirements.txt
@@ -7,3 +8,14 @@ deps=
     -rrequirements_test.txt
 commands=
     pytest --cov-append --cov=drf_swagger
+
+[testenv:flake8]
+skip_install = true
+deps=
+    flake8
+commands=
+    flake8 drf_swagger testproj
+
+[flake8]
+max-line-length = 120
+exclude = **/migrations/*