A numpy failing test for ResourceWarning on Python 3

Tests/test_image.py

@@ -514,6 +514,16 @@ class TestImage(PillowTestCase):
         with Image.open(test_file) as im:
             self.assert_warning(None, lambda: im.save('test_img.jpg'))
 
+    def test_no_resource_warning_for_numpy_array(self):
+        # https://github.com/python-pillow/Pillow/issues/835
+        # Arrange
+        from numpy import array
+        test_file = 'Tests/images/hopper.png'
+        im = Image.open(test_file)
+
+        # Act/Assert
+        self.assert_warning(None, lambda: array(im))
+
 
 class MockEncoder(object):
     pass