TypeScript创造的联合类型(Mixin)中，如何支持 prototype链判断？如何让 isInherit(C, A) 和 isInherit(C, B) 判定同时成立？-灵析社区

type Constructor> = new (...args: any[]) => T; type UnionToIntersection = (U extends any ? (k: U) => void : never) extends (k: infer I) => void ? I : never; function Mixin(...mixins: T): Constructor>> & UnionToIntersection { class Mix { static mixinClasses = mixins; } const mergeDesc: any = {}; function copyProperties(target: any, source: any) { for (let key of Reflect.ownKeys(source)) { if (key !== 'constructor' && key !== 'prototype' && key !== 'name') { let desc = Object.getOwnPropertyDescriptor(source, key); if (desc) { mergeDesc[key] = mergeDesc[key] || []; mergeDesc[key].push(desc.value); Object.defineProperty(target, key, desc); } } } } for (let mixin of mixins) { copyProperties(Mix, mixin); // 拷贝静态属性 copyProperties(Mix.prototype, mixin.prototype); // 拷贝原型属性 // 添加标识属性 Mix.prototype[`__is${mixin.name}`] = true; } for (const key in mergeDesc) { const fns = mergeDesc[key]; Object.defineProperty(Mix.prototype, key, { configurable: true, enumerable: true, writable: true, value(...args: any[]) { const context = this; fns.forEach(function (fn: Function) { fn.call(context, ...args); }); }, }); } return Mix as Constructor>> & UnionToIntersection; } class A { printA() { console.log("A"); } } class B { printB(sss: string) { console.log("B"); } } class C extends Mixin(A, B) { constructor() { super(); } printC() { this.printA(); this.printB(''); } } function isInherit(childClass: any, parentClass: any): boolean { const parentName = parentClass.name; return childClass.prototype[`__is${parentName}`] === true; } if (isInherit(C, A)) { // 判定成立 console.log('C inherit A'); } else { console.log('C not inherit A'); } if (isInherit(C, B)) { // 判定成立 console.log('C inherit B'); } else { console.log('C not inherit B'); }