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JavaScript Classのpropertyとmethodを列挙する

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色々参考にしてclassのメソッドとプロパティを列挙する方法を調べてみました。
作ってみたけど結局使わないような。
まだまだ不備があるかもしれません。

javascript
class First {
  constructor() {
    this.dataFirst = "first";
  }
  funcFirst() {
    console.log("funcFirst");
  }
  static staticFuncFirst() {
  	console.log("static funcFirst")
  }
}

class Second extends First {
  constructor() {
    super();
    this.dataSecond = "second";
  }
  funcSecond() {
    console.log("funcSecond");
  }
  static staticFuncSecond() {
  	console.log("static funcSecond")
  }
}

class Third extends Second {
  constructor() {
    super();
    this.dataThird = "third";
  }
  funcThird() {
    console.log("funcThird");
  }
  static staticFuncThird() {
  	console.log("static funcThird")
  }
}

function getAllMethodNames(object) {
  let methods = new Set();

  //Objectオブジェクトにまでたどるとobj.__proto__はnull。もしくはOwnPropertyNamesに__proto__が出てくる
  for(let obj = Object.getPrototypeOf(object); obj !== null && obj.__proto__ !== null; obj = Object.getPrototypeOf(obj)) {
    let names = Object.getOwnPropertyNames(obj)
  	names.forEach((x) => methods.add(x));
  }
  return methods;
}

function getAllStaticMethodNames(className) {
  let methods = new Set();

  //typeof __proto__ が"function"の間はユーザが定義したclass。"object"になるとObjectオブジェクト
  for(let obj = className; obj !== null && typeof obj.__proto__ === "function"; obj = Object.getPrototypeOf(obj)) {
  	let names = Object.getOwnPropertyNames(obj)
    names = names.filter((prop) => { return typeof obj[prop] === "function"; });
    names.forEach((k) => methods.add(k));
  }
  return methods;
}

function getAllPropertyNames(object) {
  let properties = new Set();

  for(let obj = object; obj !== null && typeof obj.__proto__ !== null; obj = Object.getPrototypeOf(obj)) {
  	let names = Object.keys(obj)
    names.forEach((k) => properties.add(k));
  }
  return properties;
}

let first = new First();
let second = new Second();
let third = new Third();

console.log(getAllPropertyNames(first));
console.log(getAllMethodNames(first));
console.log(getAllStaticMethodNames(First));
console.log(getAllPropertyNames(second));
console.log(getAllMethodNames(second));
console.log(getAllStaticMethodNames(Second));
console.log(getAllPropertyNames(third));
console.log(getAllMethodNames(third));
console.log(getAllStaticMethodNames(Third));
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