Method test_setdefault

Lib/test/test_dict.py:475–500

(self)

        self.assertRaises(TypeError, d.get, None, None, None)

    def test_setdefault(self):
        # dict.setdefault()
        d = {}
        self.assertIs(d.setdefault('key0'), None)
        d.setdefault('key0', [])
        self.assertIs(d.setdefault('key0'), None)
        d.setdefault('key', []).append(3)
        self.assertEqual(d['key'][0], 3)
        d.setdefault('key', []).append(4)
        self.assertEqual(len(d['key']), 2)
        self.assertRaises(TypeError, d.setdefault)

        class Exc(Exception): pass

        class BadHash(object):
            fail = False
            def __hash__(self):
                if self.fail:
                    raise Exc()
                else:
                    return 42

        x = BadHash()
        d[x] = 42
        x.fail = True
        self.assertRaises(Exc, d.setdefault, x, [])

    def test_setdefault_atomic(self):
        # Issue #13521: setdefault() calls __hash__ and __eq__ only once.