test_buffer.py 文件源码

def test_memoryview_compare_special_cases(self):

        a = array.array('L', [1, 2, 3])
        b = array.array('L', [1, 2, 7])

        # Ordering comparisons raise:
        v = memoryview(a)
        w = memoryview(b)
        for attr in ('__lt__', '__le__', '__gt__', '__ge__'):
            self.assertIs(getattr(v, attr)(w), NotImplemented)
            self.assertIs(getattr(a, attr)(v), NotImplemented)

        # Released views compare equal to themselves:
        v = memoryview(a)
        v.release()
        self.assertEqual(v, v)
        self.assertNotEqual(v, a)
        self.assertNotEqual(a, v)

        v = memoryview(a)
        w = memoryview(a)
        w.release()
        self.assertNotEqual(v, w)
        self.assertNotEqual(w, v)

        # Operand does not implement the buffer protocol:
        v = memoryview(a)
        self.assertNotEqual(v, [1, 2, 3])

        # NaNs
        nd = ndarray([(0, 0)], shape=[1], format='l x d x', flags=ND_WRITABLE)
        nd[0] = (-1, float('nan'))
        self.assertNotEqual(memoryview(nd), nd)

        # Depends on issue #15625: the struct module does not understand 'u'.
        a = array.array('u', 'xyz')
        v = memoryview(a)
        self.assertNotEqual(a, v)
        self.assertNotEqual(v, a)

        # Some ctypes format strings are unknown to the struct module.
        if ctypes:
            # format: "T{>l:x:>l:y:}"
            class BEPoint(ctypes.BigEndianStructure):
                _fields_ = [("x", ctypes.c_long), ("y", ctypes.c_long)]
            point = BEPoint(100, 200)
            a = memoryview(point)
            b = memoryview(point)
            self.assertNotEqual(a, b)
            self.assertNotEqual(a, point)
            self.assertNotEqual(point, a)
            self.assertRaises(NotImplementedError, a.tolist)