'From #2995, test that hstack\'ing references to the same table has the
expected output.'

def test_stack_same_table(self, operation_table_type):

    self._setup(operation_table_type)
    out = table.hstack([self.t1, self.t1])
    assert (out.pformat() == ['a_1    b_1    a_2    b_2', '---    ---    ---    ---', '0.0    foo    0.0    foo', '1.0    bar    1.0    bar'])
