列印Proxy物件和ref物件的包實現詳解

// 記錄使用者new Proxy操作的所有物件
// WeakSet，WeakMap，都是弱參照，不干預其他模組的垃圾回收機制
export const proxyMap = new WeakMap()
let OriginalProxy = null
export function listenProxy() {
    if (OriginalProxy) { // 防止使用者多次呼叫監聽
        return
    }
    OriginalProxy = window.Proxy
    window.Proxy = new Proxy(Proxy, {
        construct(target, args) {
            const newProxy = new OriginalProxy(...args)
            proxyInstances.set(newProxy, target)
            return newProxy
        },
        get(obj, prop) {
            // https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Symbol/hasInstance
            if (prop === Symbol.hasInstance) { // 監控 `instanceof` 關鍵字
                return instance => proxyMap.has(instance)
            }
            // https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Reflect/get
            return Reflect.get(...arguments)
        }
    })
}
export function unListenProxy() {
    window.Proxy = OriginalProxy || window.Proxy
}

export function getOrg(obj) {
    return proxyMap.get(obj)
}
// 深克隆
export function clone(obj, _refs = new WeakSet()) {
    if (obj === null || obj === undefined) return null
    if (typeof obj !== 'object') return obj
    if (obj.constructor === Date) return new Date(obj)
    if (obj.constructor === RegExp) return new RegExp(obj)
    const newObj = new obj.constructor() //保持繼承的原型
    for (const key in obj) {
        if (obj.hasOwnProperty(key)) {
            const val = obj[key]
            if (typeof val === 'object' && !_refs.has(val)) {
                newObj[key] = clone(val)
            } else {
                newObj[key] = val
            }
        }
    }
    return newObj
}

import { listenProxy, unListenProxy, clone, getOrg } from "./until";
let config = {
    key: 'log', // any String
    type: 'trace', // 'trace' | 'error' | 'any String'
    cloneProxy: getOrg
}
let Vue = {}
export default function (obj = {}, vue) {
    Vue = vue || {}
    config = { ...config, ...obj }
    if (obj.copy === 'clone') {
        config.cloneProxy = clone
    }
    listenLog(config)
}
// ----------------------------------------
const { groupCollapsed, groupEnd, trace, log } = console
// const type = 'trace' | 'error' | ''
function listenLog() {
    const isRef = Vue.isRef || (obj => {
        return typeof obj === 'object' && !!obj.constructor && obj.constructor.name === 'RefImpl'
    })
    const unref = Vue.unref || (obj => obj.value)
    const { key, type, cloneProxy } = config
    if (!key) {
        console.error('Missing required parameter: key')
    }
    listenProxy() // 為 new Proxy 物件新增 `instanceof` 支援
    console[key] = function (...arr) {
        const newArr = arr.map(i => {
            if (isRef(i)) {
                return unref(i)
            } else if (i instanceof Proxy) {
                return cloneProxy(i)
            } else {
                return i
            }
        })
        groupCollapsed(...newArr)
        // 以 trace
        if (type === 'trace') {
            // trace(...newArr)
            console.log('第二行即為呼叫者所在的檔案位置')
            trace('The second line is the file location of the caller')
            groupEnd()
            return
        }
        let stack = new Error().stack || ''
        // stack = stack.replace('Error', 'Log')
        if (type === 'error') {
            log('%c這不是一個錯誤，請點選第二行的"at"，跳轉到對應的檔案', 'color: #008000')
            log('%cThis is not an error. Please click "at" in the second line to jump to the corresponding file', 'color: #008000')
            log(stack)
            groupEnd()
            return;
        }
        // 簡單輸入模式，控制檯看起來是簡單了，卻失去了點選連結直接跳轉到對應檔案的功能
        const stackArr = stack.match(/at.*s/g) || []
        log(stackArr[1])
        groupEnd()
    }
}