你也没有 hash 在控制台中。这是有错误的行:

            newBlock.hash = newBlock.calculateHash

calculateHash 是一个函数

            newBlock.hash = newBlock.calculateHash()

现在它开始工作了:

{
    "chain": [
        null,
        {
            "index": 1,
            "timestamp": "10/07/2017",
            "data": {
                "amount": 4
            },
            "hash": "8f84adcf036e9aa052a4d7e689c7b8b06070b851eff535870f5cb8f7d53ab05a"
        },
        {
            "index": 2,
            "timestamp": "12/07/2017",
            "data": {
                "amount": 10
            },
            "previousHash": "8f84adcf036e9aa052a4d7e689c7b8b06070b851eff535870f5cb8f7d53ab05a",
            "hash": "a2479e7df8f2a61f97f3ae4830aff93c0d43041b4a7cbb8079c2309a915d8945"
        }
    ]
}