test for deprecation warning

scrapy/pipelines/images.py

@@ -141,7 +141,7 @@ class ImagesPipeline(FilesPipeline):
             from scrapy.exceptions import ScrapyDeprecationWarning
             import warnings
             warnings.warn('ImagesPipeline.convert_image() method overriden in a incompatible way, '
-                          'overriden method does not accept response_body attribute.',
+                          'overriden method does not accept response_body argument.',
                           category=ScrapyDeprecationWarning, stacklevel=1)
 
         convert_image_overriden = _is_convert_image_overriden()
@@ -162,6 +162,13 @@ class ImagesPipeline(FilesPipeline):
             yield thumb_path, thumb_image, thumb_buf
 
     def convert_image(self, image, size=None, response_body=None):
+        if not response_body:
+            from scrapy.exceptions import ScrapyDeprecationWarning
+            import warnings
+            warnings.warn('ImagesPipeline.convert_image() method called in a incompatible way, '
+                          'method called without response_body argument.',
+                          category=ScrapyDeprecationWarning, stacklevel=1)
+
         if image.format == 'PNG' and image.mode == 'RGBA':
             background = Image.new('RGBA', image.size, (255, 255, 255))
             background.paste(image, image)
@@ -177,15 +184,8 @@ class ImagesPipeline(FilesPipeline):
         if size:
             image = image.copy()
             image.thumbnail(size, Image.ANTIALIAS)
-        else: 
-            if not response_body:
-                from scrapy.exceptions import ScrapyDeprecationWarning
-                import warnings
-                warnings.warn('ImagesPipeline.convert_image() method called in a incompatible way, '
-                              'method called without response_body attribute.',
-                              category=ScrapyDeprecationWarning, stacklevel=1)
-            elif image.format == 'JPEG':
-                return image, response_body
+        elif response_body and image.format == 'JPEG':
+            return image, response_body
                 
         buf = BytesIO()
         image.save(buf, 'JPEG')

tests/test_pipeline_images.py

@@ -76,37 +76,48 @@ class ImagesPipelineTestCase(unittest.TestCase):
                          'thumbs/50/850233df65a5b83361798f532f1fc549cd13cbe9.jpg')
 
     def test_convert_image(self):
-        SIZE = (100, 100)
-        # straigh forward case: RGB and JPEG
+        # tests for old API
+        with warnings.catch_warnings(record=True) as w:
+            warnings.simplefilter('always')
+            
+            SIZE = (100, 100)
+            # straigh forward case: RGB and JPEG
+            COLOUR = (0, 127, 255)
+            im, buf = _create_image('JPEG', 'RGB', SIZE, COLOUR)
+            converted, converted_buf = self.pipeline.convert_image(im)
+            self.assertEqual(converted.mode, 'RGB')
+            self.assertEqual(converted.getcolors(), [(10000, COLOUR)])
+
+            # check that thumbnail keep image ratio
+            thumbnail, _ = self.pipeline.convert_image(converted, size=(10, 25))
+            self.assertEqual(thumbnail.mode, 'RGB')
+            self.assertEqual(thumbnail.size, (10, 10))
+
+            # transparency case: RGBA and PNG
+            COLOUR = (0, 127, 255, 50)
+            im, buf = _create_image('PNG', 'RGBA', SIZE, COLOUR)
+            converted, _ = self.pipeline.convert_image(im)
+            self.assertEqual(converted.mode, 'RGB')
+            self.assertEqual(converted.getcolors(), [(10000, (205, 230, 255))])
+
+            # transparency case with palette: P and PNG
+            COLOUR = (0, 127, 255, 50)
+            im, buf = _create_image('PNG', 'RGBA', SIZE, COLOUR)
+            im = im.convert('P')
+            converted, _ = self.pipeline.convert_image(im)
+            self.assertEqual(converted.mode, 'RGB')
+            self.assertEqual(converted.getcolors(), [(10000, (205, 230, 255))])
+
+            # ensure that we recieved deprecation warnings
+            self.assertTrue(len(w) >= 4)
+
+        # tests for new API
+        # check that we don't convert JPEGs again
         COLOUR = (0, 127, 255)
         im, buf = _create_image('JPEG', 'RGB', SIZE, COLOUR)
         converted, converted_buf = self.pipeline.convert_image(im, response_body=buf)
-        self.assertEqual(converted.mode, 'RGB')
-        self.assertEqual(converted.getcolors(), [(10000, COLOUR)])
-        # check that we don't convert JPEGs again
         self.assertEqual(converted_buf, buf)
 
-        # check that thumbnail keep image ratio
-        thumbnail, _ = self.pipeline.convert_image(converted, size=(10, 25), response_body=converted_buf)
-        self.assertEqual(thumbnail.mode, 'RGB')
-        self.assertEqual(thumbnail.size, (10, 10))
-
-        # transparency case: RGBA and PNG
-        COLOUR = (0, 127, 255, 50)
-        im, buf = _create_image('PNG', 'RGBA', SIZE, COLOUR)
-        converted, _ = self.pipeline.convert_image(im, response_body=buf)
-        self.assertEqual(converted.mode, 'RGB')
-        self.assertEqual(converted.getcolors(), [(10000, (205, 230, 255))])
-
-        # transparency case with palette: P and PNG
-        COLOUR = (0, 127, 255, 50)
-        im, buf = _create_image('PNG', 'RGBA', SIZE, COLOUR)
-        im = im.convert('P')
-        converted, _ = self.pipeline.convert_image(im, response_body=buf)
-        self.assertEqual(converted.mode, 'RGB')
-        self.assertEqual(converted.getcolors(), [(10000, (205, 230, 255))])
-
-
 class DeprecatedImagesPipeline(ImagesPipeline):
     def file_key(self, url):
         return self.image_key(url)