'L{util.InsensitiveDict} does not preserves the case of keys if
constructed with C{preserve=False}.'

def test_noPreserve(self):

    dct = util.InsensitiveDict({'Foo': 'bar', 1: 2, 'fnz': {1: 2}}, preserve=0)
    keys = ['foo', 'fnz', 1]
    for x in keys:
        self.assertIn(x, dct.keys())
        self.assertIn((x, dct[x]), dct.items())
    self.assertEqual(len(keys), len(dct))
    del dct[1]
    del dct['foo']
    self.assertEqual(dct.keys(), ['fnz'])
