Slightly simplify our conditionals

Test warnings by default

flake8/engine.py

@@ -9,7 +9,7 @@ from flake8 import __version__
 from flake8 import callbacks
 from flake8.reporter import (multiprocessing, BaseQReport, FileQReport,
                              QueueReport)
-from flake8.util import OrderedSet, is_windows, is_using_stdin
+from flake8 import util
 
 _flake8_noqa = re.compile(r'\s*# flake8[:=]\s*noqa', re.I).search
 
@@ -18,7 +18,7 @@ EXTRA_EXCLUDE = ['.tox', '.eggs', '*.egg']
 
 def _register_extensions():
     """Register all the extensions."""
-    extensions = OrderedSet()
+    extensions = util.OrderedSet()
     extensions.add(('pep8', pep8.__version__))
     parser_hooks = []
     options_hooks = []
@@ -124,17 +124,14 @@ def get_style_guide(**kwargs):
     for options_hook in options_hooks:
         options_hook(options)
 
-    if (options.verbose
+    if util.warn_when_using_jobs(options):
-            and options.jobs
-            and options.jobs.isdigit()
-            and int(options.jobs) > 1):
         if not multiprocessing:
             warnings.warn("The multiprocessing module is not available. "
                           "Ignoring --jobs arguments.")
-        if is_windows():
+        if util.is_windows():
             warnings.warn("The --jobs option is not available on Windows. "
                           "Ignoring --jobs arguments.")
-        if is_using_stdin(styleguide.paths):
+        if util.is_using_stdin(styleguide.paths):
             warnings.warn("The --jobs option is not compatible with supplying "
                           "input using - . Ignoring --jobs arguments.")
         if options.diff:
@@ -145,7 +142,7 @@ def get_style_guide(**kwargs):
     if options.diff:
         options.jobs = None
 
-    force_disable_jobs = is_windows() or is_using_stdin(styleguide.paths)
+    force_disable_jobs = util.force_disable_jobs(styleguide)
 
     if multiprocessing and options.jobs and not force_disable_jobs:
         if options.jobs.isdigit():

flake8/tests/test_engine.py

@@ -39,6 +39,7 @@ class TestEngine(unittest.TestCase):
             with mock.patch('flake8.engine.get_parser') as get_parser:
                 m.ignored_extensions = []
                 StyleGuide.return_value.options.jobs = '42'
+                StyleGuide.return_value.options.diff = False
                 get_parser.return_value = (m, [])
                 engine.get_style_guide(foo='bar')
                 get_parser.assert_called_once_with()
@@ -85,13 +86,13 @@ class TestEngine(unittest.TestCase):
         # ourselves) what system we may be testing on.
 
     def test_windows_disables_jobs(self):
-        with mock.patch('flake8.engine.is_windows') as is_windows:
+        with mock.patch('flake8.util.is_windows') as is_windows:
             is_windows.return_value = True
             guide = engine.get_style_guide()
             assert isinstance(guide, reporter.BaseQReport) is False
 
     def test_stdin_disables_jobs(self):
-        with mock.patch('flake8.engine.is_using_stdin') as is_using_stdin:
+        with mock.patch('flake8.util.is_using_stdin') as is_using_stdin:
             is_using_stdin.return_value = True
             guide = engine.get_style_guide()
             assert isinstance(guide, reporter.BaseQReport) is False

flake8/util.py

@@ -54,6 +54,15 @@ def is_using_stdin(paths):
     return '-' in paths
 
 
+def warn_when_using_jobs(options):
+    return (options.verbose and options.jobs and options.jobs.isdigit() and
+            int(options.jobs) > 1)
+
+
+def force_disable_jobs(styleguide):
+    return is_windows() or is_using_stdin(styleguide.paths)
+
+
 def flag_on(val):
     """Return true if flag is on"""
     return str(val).upper() in ('1', 'T', 'TRUE', 'ON')

tox.ini

@@ -6,12 +6,10 @@ envlist =
 [testenv]
 usedevelop = True
 deps =
-    nose
     mock
 commands =
     python setup.py test -q
     python setup.py flake8
-    nosetests flake8.tests._test_warnings
 
 [testenv:py27-flake8]
 basepython = python2.7