HookMap.js 1021 Bytes
/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/
"use strict";

class HookMap {
	constructor(factory) {
		this._map = new Map();
		this._factory = factory;
		this._interceptors = [];
	}

	get(key) {
		return this._map.get(key);
	}

	for(key) {
		const hook = this.get(key);
		if (hook !== undefined) {
			return hook;
		}
		let newHook = this._factory(key);
		const interceptors = this._interceptors;
		for (let i = 0; i < interceptors.length; i++) {
			newHook = interceptors[i].factory(key, newHook);
		}
		this._map.set(key, newHook);
		return newHook;
	}

	intercept(interceptor) {
		this._interceptors.push(
			Object.assign(
				{
					factory: (key, hook) => hook
				},
				interceptor
			)
		);
	}

	tap(key, options, fn) {
		return this.for(key).tap(options, fn);
	}

	tapAsync(key, options, fn) {
		return this.for(key).tapAsync(options, fn);
	}

	tapPromise(key, options, fn) {
		return this.for(key).tapPromise(options, fn);
	}
}

module.exports = HookMap;