python类cached_property()的实例源码

def test_cached_property(self):
        foo = []
        class A(object):
            def prop(self):
                foo.append(42)
                return 42
            prop = utils.cached_property(prop)

        a = A()
        p = a.prop
        q = a.prop
        self.assert_true(p == q == 42)
        self.assert_equal(foo, [42])

        foo = []
        class A(object):
            def _prop(self):
                foo.append(42)
                return 42
            prop = utils.cached_property(_prop, name='prop')
            del _prop

        a = A()
        p = a.prop
        q = a.prop
        self.assert_true(p == q == 42)
        self.assert_equal(foo, [42])

def test_cached_property_doc(self):
        @utils.cached_property
        def foo():
            """testing"""
            return 42
        self.assert_equal(foo.__doc__, 'testing')
        self.assert_equal(foo.__name__, 'foo')
        self.assert_equal(foo.__module__, __name__)