public void TwoIntegerTokensWitDifferentValueAreNotEqual()
        {
            var token = new NumberToken(654);
            var token2 = new NumberToken(123);

            Assert.AreNotEqual(token, token2);
        }
        public void TwoIntegerTokensWithSameValueAreEqual()
        {
            var token = new NumberToken(654);
            var token2 = new NumberToken(654);

            Assert.AreEqual(token, token2);
        }
 public void StringRepresentationIsCorrect()
 {
     var token = new NumberToken(654);
     Assert.AreEqual("<number - '654'>", token.ToString());
 }