object-map.ts

export const equals = (a: any, b: any): boolean => {
  if (a === b) {
    return true;
  }
  if (a instanceof Date && b instanceof Date) {
    return a.getTime() === b.getTime();
  }
  if (!a || !b || (typeof a !== "object" && typeof b !== "object")) {
    return a === b;
  }
  if (a.prototype !== b.prototype) {
    return false;
  }
  const keys = Object.keys(a);
  if (keys.length !== Object.keys(b).length) {
    return false;
  }
  return keys.every((k) => equals(a[k], b[k]));
};

export default class ObjectMap<K extends object, V> extends WeakMap<K, V> {
  private map: Map<K, V>;
  public [Symbol.toStringTag]: string;

  public constructor() {
    super();
    this.map = new Map<K, V>();
  }

  public delete(key: K): boolean {
    const k = this.key(key);
    return this.map.delete(k);
  }

  private key(key: K): K {
    return [...this.map.keys()].find((x) => equals(x, key)) as any;
  }

  public get(key: K): V | undefined {
    const k = this.key(key);
    if (!!k) {
      return this.map.get(k);
    }
  }

  public set(key: K, val: V) {
    this.map.set(key, val);
    return this;
  }

  public has(key: K): boolean {
    const k = this.key(key);
    return this.map.has(k);
  }
}