The functionnumpy.testing.assert_array_compare has no docstring, and does not appear in the online documentation. My guess is that the authors intended the function to be private. If that is the case, the function should be renamed to _assert_array_compare, or removed from the numpy.testing namespace. Given the lack of any documentation, we could probably do that without a deprecation.

If, on the other hand, assert_array_compare is intended to be a public function, then it needs a docstring.