avocado-old/packages/behavior/item/collection.js

import {fromJSON as behaviorItemFromJSON} from './registry';

export function Collection(type) {
  const plural = `${type}s`;
  return class Collection {

    static type() {
      return plural;
    }
  
    constructor() {
      this[plural] = [];
    }

    clone(other) {
      if (0 === other[plural].length) {
        return;
      }
      const Item = other[plural][0].constructor;
      for (let i = 0; i < other[plural].length; ++i) {
        this[plural][i] = new Item();
        this[plural][i].clone(other[plural][i]);
      }
    }

    createClone() {
      const Items = this.constructor;
      const items = new Items();
      items.clone(this);
      return items;
    }

    count() {
      return this[plural].length;
    }

    fromJSON(json) {
      this[plural] = [];
      for (const item of json[plural]) {
        this[plural].push(behaviorItemFromJSON(item));
      }
      return this;
    }

    toJSON() {
      return this[plural].map((item) => item.toJSON());
    }

  };
}