'L{ListOf.fromBox} correctly reverses the operation performed by
L{ListOf.toBox} for optional arguments.'

def test_omittedOptionalArgumentDeserializesAsNone(self):

    stringList = amp.ListOf(amp.Integer(), optional=True)
    objects = {}
    stringList.fromBox('omitted', {}, objects, None)
    self.assertEqual(objects, {'omitted': None})
