Return instance instead of list for ImagePropertiesAnnotation.

system_tests/vision.py

@@ -497,9 +497,7 @@ def test_detect_properties_content(self):
         with open(FACE_FILE, 'rb') as image_file:
             image = client.image(content=image_file.read())
         properties = image.detect_properties()
-        self.assertEqual(len(properties), 1)
-        image_property = properties[0]
-        self._assert_properties(image_property)
+        self._assert_properties(properties[0])
 
     def test_detect_properties_gcs(self):
         client = Config.CLIENT
@@ -514,14 +512,10 @@ def test_detect_properties_gcs(self):
 
         image = client.image(source_uri=source_uri)
         properties = image.detect_properties()
-        self.assertEqual(len(properties), 1)
-        image_property = properties[0]
-        self._assert_properties(image_property)
+        self._assert_properties(properties[0])
 
     def test_detect_properties_filename(self):
         client = Config.CLIENT
         image = client.image(filename=FACE_FILE)
         properties = image.detect_properties()
-        self.assertEqual(len(properties), 1)
-        image_property = properties[0]
-        self._assert_properties(image_property)
+        self._assert_properties(properties[0])

vision/google/cloud/vision/annotations.py

@@ -166,7 +166,7 @@ def _make_image_properties_from_pb(image_properties):
     :rtype: list
     :returns: List of ``ImageProperties``.
     """
-    return ImagePropertiesAnnotation.from_pb(image_properties)
+    return [ImagePropertiesAnnotation.from_pb(image_properties)]
 
 
 def _entity_from_response_type(feature_type, results):

vision/google/cloud/vision/color.py

@@ -56,7 +56,7 @@ def from_pb(cls, image_properties):
         """
         colors = getattr(image_properties.dominant_colors, 'colors', ())
         if len(colors) > 0:
-            return [cls([ColorInformation.from_pb(color) for color in colors])]
+            return cls([ColorInformation.from_pb(color) for color in colors])
 
     @property
     def colors(self):

vision/unit_tests/test_color.py

@@ -96,10 +96,8 @@ def test_color_annotation_from_pb(self):
             dominant_colors=dominant_colors)
 
         color_info = self._get_target_class()
-        image_properties_result = color_info.from_pb(image_properties_pb)
+        image_properties = color_info.from_pb(image_properties_pb)
 
-        self.assertEqual(len(image_properties_result), 1)
-        image_properties = image_properties_result[0]
         self.assertEqual(image_properties.colors[0].pixel_fraction, 1.0)
         self.assertEqual(image_properties.colors[0].score, 1.0)
         self.assertEqual(image_properties.colors[0].color.red, 1.0)