def test_sparsity_null_maps(self, backend):
        s = op2.Set(5)
        with pytest.raises(MapValueError):
            m = op2.Map(s, s, 1)
            op2.Sparsity((s, s), (m, m))
Building sparsity from a pair of non-initialized maps should fail.
dataset/ETHPy150Open OP2/PyOP2/test/unit/test_matrices.py/TestSparsity.test_sparsity_null_maps