如何实现一个 plugin 插件

webpack-plugin

• 基于 tapable 扩展出的，事件广播
• 插件 time-webpack-plugin

class TimePlugin {
  constructor() {
    console.time("time");
  }
  apply(compiler) {
    compiler.hooks.afterEmit.tapAsync("TimePlugin", (compilation, callback) => {
      console.timeEnd("time");
      callback();
    });
  }
}

module.exports = TimePlugin;

• 配置文件

const TimePlugin = require("./time.webpack");
// ....
config.plugins.push(new TimePlugin());

let compiler = new Compiler({});
// 加载插件
if (options.plugins && Array.isArray(options.plugins)) {
  for (const plugin of options.plugins) {
    plugin.apply(compiler);
  }
}