test_elementtree.py 文件源码

def test_element_indexing_negative(self):
        Element = self.etree.Element
        SubElement = self.etree.SubElement
        a = Element('a')
        b = SubElement(a, 'b')
        c = SubElement(a, 'c')
        d = SubElement(a, 'd')
        self.assertEqual(d, a[-1])
        self.assertEqual(c, a[-2])
        self.assertEqual(b, a[-3])
        self.assertRaises(IndexError, operator.getitem, a, -4)
        a[-1] = e = Element('e')
        self.assertEqual(e, a[-1])
        del a[-1]
        self.assertEqual(2, len(a))