'Regression test to fix memory allocation issues (use 3+ inclusive NS spaces)'

def test_c14n_tostring_inclusive_ns_prefixes(self):

    tree = self.parse(_bytes('<a    xmlns:x="http://abc"    xmlns:y="http://bcd"    xmlns:z="http://cde"><z:b/></a>'))
    s = etree.tostring(tree, method='c14n', exclusive=True, inclusive_ns_prefixes=['x', 'y', 'z'])
    self.assertEqual(_bytes('<a    xmlns:x="http://abc"    xmlns:y="http://bcd"    xmlns:z="http://cde"><z:b></z:b></a>'), s)
