Fix skipping of engine testcases

CONTRIBUTING.rst

@@ -23,7 +23,7 @@ engine.
 
 .. code-block:: python
 
-    @unittest.skipIf(not has_pillow(), 'Pillow not installed')
+    @unittest.skipIf(not has_installed('pillow'), 'Pillow not installed')
     class PillowEngineTestCase(EngineTestMixin, unittest.TestCase):
         ENGINE = PillowEngine
 

tests/test_cache_backends.py

@@ -6,7 +6,7 @@
 from thumbnails.images import Thumbnail
 
 from .compat import mock
-from .utils import has_django, has_redis
+from .utils import has_installed
 
 
 class CacheBackendTestMixin(object):
@@ -48,12 +48,12 @@ class SimpleCacheBackendTestCase(CacheBackendTestMixin, unittest.TestCase):
     BACKEND = SimpleCacheBackend
 
 
-@unittest.skipIf(not has_django(), 'Django is not installed')
+@unittest.skipIf(not has_installed('django'), 'Django is not installed')
 class DjangoCacheBackendTestCase(CacheBackendTestMixin, unittest.TestCase):
     BACKEND = DjangoCacheBackend
 
 
-@unittest.skipIf(not has_redis(), 'Redis not installed')
+@unittest.skipIf(not has_installed('redis'), 'Redis not installed')
 class RedisCacheBackendTestCase(CacheBackendTestMixin, unittest.TestCase):
     BACKEND = RedisCacheBackend
 

tests/test_conf.py

@@ -6,7 +6,7 @@
 from thumbnails.conf.wrapper import SettingsWrapper
 
 from .compat import mock
-from .utils import has_django
+from .utils import has_installed
 
 
 class SettingsWrapperTestCase(unittest.TestCase):
@@ -26,7 +26,7 @@ def test_override_by_thumbnail_settings_module(self):
         settings = SettingsWrapper()
         self.assertEqual(settings.THUMBNAIL_ENGINE, 'thumbnails.engines.PillowEngine')
 
-    @unittest.skipIf(not has_django(), 'Django not installed')
+    @unittest.skipIf(not has_installed('django'), 'Django not installed')
     def test_django_defaults(self):
         settings = SettingsWrapper()
         self.assertEqual(

tests/test_engines.py

@@ -11,7 +11,7 @@
 from thumbnails.images import SourceFile, Thumbnail
 
 from .compat import mock
-from .utils import has_installed
+from .utils import is_tox_env
 
 
 class EngineTestMixin(object):
@@ -193,7 +193,7 @@ def test_create_from_url(self):
         self.assertEqual(thumbnail.url, 'http://puppies.lkng.me/200x300')
 
 
-@unittest.skipIf(not has_installed('PIL'), 'Pillow not installed')
+@unittest.skipIf(not is_tox_env('pillow'), 'not pillow environment')
 class PillowEngineTestCase(EngineTestMixin, unittest.TestCase):
     ENGINE = PillowEngine
     RAW_DATA_HASH = 'cd63a4ccd85070c76db822ca5ccb11ba59966256'
@@ -211,13 +211,13 @@ def test_load_with_os_error(self, mock_image_load):
         mock_image_load.assert_called_once()
 
 
-@unittest.skipIf(not has_installed('wand.image'), 'Wand not installed')
+@unittest.skipIf(not is_tox_env('wand'), 'not wand environment')
 class WandEngineTestCase(EngineTestMixin, unittest.TestCase):
     ENGINE = WandEngine
     RAW_DATA_HASH = '8eb021308a7fb04cb0e87ce9026828f42e8a4a81'
 
 
-@unittest.skipIf(not has_installed('pgmagick'), 'pgmagick not installed')
+@unittest.skipIf(not is_tox_env('pgmagick'), 'not pgmagick environment')
 class PgmagickEngineTestCase(EngineTestMixin, unittest.TestCase):
     ENGINE = PgmagickEngine
     RAW_DATA_HASH = '47be661ff0e19f6e78eaa38b68db74d10f3f4c96'

tests/test_storage_backends.py

@@ -3,7 +3,7 @@
 import shutil
 import unittest
 
-from tests.utils import has_django
+from tests.utils import has_installed
 from thumbnails.storage_backends import (BaseStorageBackend, DjangoStorageBackend,
                                          FilesystemStorageBackend)
 
@@ -43,6 +43,6 @@ def test_create_location_in_init(self):
         os.path.exists(instance.location)
 
 
-@unittest.skipIf(not has_django(), 'Django not installed')
+@unittest.skipIf(not has_installed('django'), 'Django not installed')
 class DjangoStorageBackendTestCase(StorageBackendTestMixin, unittest.TestCase):
     BACKEND = DjangoStorageBackend

tests/utils.py

@@ -12,6 +12,11 @@ def has_installed(dependency):
         return False
 
 
+def is_tox_env(env):
+    if 'VIRTUAL_ENV' in os.environ:
+        return env in os.environ['VIRTUAL_ENV']
+
+
 def has_django():
     return has_installed('django')
 

thumbnails/__init__.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
-from thumbnails import helpers
 from thumbnails.conf import settings
 from thumbnails.engines import DummyEngine
+from thumbnails.helpers import get_engine, generate_filename, get_cache_backend
 from thumbnails.images import SourceFile, Thumbnail
 
 
@@ -29,11 +29,11 @@ def get_thumbnail(original, size, **options):
                    detected file type as well as the one specified in ``THUMBNAIL_FALLBACK_FORMAT``.
     :return: A Thumbnail object
     """
-    engine = helpers.get_engine()
-    cache = helpers.get_cache_backend()
+    engine = get_engine()
+    cache = get_cache_backend()
     original = SourceFile(original)
     crop = options.get('crop', None)
-    thumbnail_name = helpers.generate_filename(original, size, crop, options)
+    thumbnail_name = generate_filename(original, size, crop, options)
 
     if settings.THUMBNAIL_DUMMY:
         engine = DummyEngine()

thumbnails/conf/__init__.py

@@ -1,4 +1,2 @@
 # -*- coding: utf-8 -*-
-from . import wrapper
-
-settings = wrapper.SettingsWrapper()
+from thumbnails.conf.wrapper import settings  # noqa

thumbnails/conf/wrapper.py

@@ -53,3 +53,5 @@ def _load_from_module(self, _module, target):
         for setting in dir(_module):
             if not setting.startswith('_'):
                 target[setting] = getattr(_module, setting)
+
+settings = SettingsWrapper()

thumbnails/engines/__init__.py

@@ -1,15 +1,21 @@
 # -*- coding: utf-8 -*-
 from thumbnails.engines.base import BaseThumbnailEngine  # noqa
-from thumbnails.engines.pillow import PillowEngine  # noqa
 from thumbnails.engines.dummy import DummyEngine  # noqa
 
+
+try:
+    from thumbnails.engines.pillow_engine import PillowEngine  # noqa
+except ImportError:
+    PillowEngine = None
+
+
 try:
-    from thumbnails.engines.wand import WandEngine  # noqa
+    from thumbnails.engines.wand_engine import WandEngine  # noqa
 except ImportError:
     WandEngine = None
 
 
 try:
-    from thumbnails.engines.pgmagick import PgmagickEngine  # noqa
+    from thumbnails.engines.pgmagick_engine import PgmagickEngine  # noqa
 except ImportError:
     PgmagickEngine = None

thumbnails/engines/pgmagick.py → thumbnails/engines/pgmagick_engine.py

@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import
-
 from base64 import b64decode
 
 from pgmagick import Blob, Geometry, Image, ImageType
@@ -10,7 +8,7 @@
 
 class PgmagickEngine(BaseThumbnailEngine):
     """
-    Image backend for pgmagick, requires the pgpmagick package.
+    Image backend for pgmagick, requires the pgmagick package.
     """
 
     def engine_load_image(self, original):
@@ -61,4 +59,3 @@ def engine_get_format(self, image):
         if _format == 'CompuServe graphics interchange format':
             return 'GIF'
         return _format
-

thumbnails/engines/wand.py → thumbnails/engines/wand_engine.py

@@ -1,6 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import
-
 from wand.image import Image
 
 from .base import BaseThumbnailEngine