More robust assertion checks in test_to_tensor_video (#4258)

Author: NicolasHug

test/test_transforms_video.py

@@ -133,12 +133,16 @@ def test_to_tensor_video(self):
         with pytest.raises(TypeError):
             np_rng = np.random.RandomState(0)
             trans(np_rng.rand(numFrames, height, width, 1).tolist())
+        with pytest.raises(TypeError):
             trans(torch.rand((numFrames, height, width, 1), dtype=torch.float))
 
         with pytest.raises(ValueError):
             trans(torch.ones((3, numFrames, height, width, 3), dtype=torch.uint8))
+        with pytest.raises(ValueError):
             trans(torch.ones((height, width, 3), dtype=torch.uint8))
+        with pytest.raises(ValueError):
             trans(torch.ones((width, 3), dtype=torch.uint8))
+        with pytest.raises(ValueError):
             trans(torch.ones((3), dtype=torch.uint8))
 
         trans.__repr__()