@antv/event-emitter

--- package.json (entry) ---
{
  "name": "@antv/event-emitter",
  "version": "0.1.3",
  "description": "event emitter for antvis.",
  "license": "MIT",
  "main": "lib/index.js",
  "module": "esm/index.js",
  "types": "lib/index.d.ts",
  "files": [
    "src",
    "lib",
    "esm",
    "README.md",
    "LICENSE"
  ],
  "publishConfig": {
    "access": "public"
  },
  "repository": {
    "type": "git",
    "url": "git@github.com:antvis/event-emitter.git"
  },
  "scripts": {
    "build": "run-s clean lib",
    "clean": "rimraf lib esm",
    "lib": "run-p lib:*",
    "lib:cjs": "tsc -p tsconfig.json --target ES5 --module commonjs --outDir lib",
    "lib:esm": "tsc -p tsconfig.json --target ES5 --module ESNext --outDir esm",
    "test": "jest"
  },
  "devDependencies": {
    "@types/jest": "^24.0.18",
    "jest": "^24.9.0",
    "jest-electron": "^0.1.7",
    "npm-run-all": "^4.1.5",
    "prettier": "^2.0.2",
    "rimraf": "^2.6.2",
    "ts-jest": "^24.1.0",
    "typescript": "^3.6.4"
  },
  "jest": {
    "preset": "ts-jest",
    "runner": "jest-electron/runner",
    "testEnvironment": "jest-electron/environment",
    "collectCoverage": true,
    "collectCoverageFrom": [
      "src/**/*.ts",
      "!**/node_modules/*

--- index.js (entry) ---
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
var WILDCARD = '*';
/* event-emitter */
var EventEmitter = /** @class */ (function () {
    function EventEmitter() {
        this._events = {};
    }
    /**
     * 监听一个事件
     * @param evt
     * @param callback
     * @param once
     */
    EventEmitter.prototype.on = function (evt, callback, once) {
        if (!this._events[evt]) {
            this._events[evt] = [];
        }
        this._events[evt].push({
            callback: callback,
            once: !!once,
        });
        return this;
    };
    /**
     * 监听一个事件一次
     * @param evt
     * @param callback
     */
    EventEmitter.prototype.once = function (evt, callback) {
        return this.on(evt, callback, true);
    };
    /**
     * 触发一个事件
     * @param evt
     * @param args
     */
    EventEmitter.prototype.emit = function (evt) {
        var _this = this;
        var args = [];
        for (var _i = 1; _i < arguments.length; _i++) {
            args[_i - 1] = arguments[_i];
        }
        var events = this._events[evt] || [];
        var wildcardEvents = this._events[WILDCARD] || [];
        // 实际的处理 emit 方法
        var doE