def METHOD_NAME(self):
    arr = np.zeros((20, 20, 4), dtype=np.uint8)
    da = DataArray(arr, dims=['x', 'y', 'band'])
    rs = XarraySource(da, IdentityCRSTransformer())
    chips = list(sliding_chip_stream([rs], chip_sz=10, stride=10))
    self.assertEqual(len(chips), 0)