unenv/runtime/node/events/_events.cjs

`unenv` is a framework-agnostic system that allows converting JavaScript code to be platform agnostic and work in any environment including Browsers, Workers, Node.js, or JavaScript runtime.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.EventEmitter = void 0;
exports.once = once;
let defaultMaxListeners = 10;
class EventEmitter {
  __unenv__ = true;
  _events = /* @__PURE__ */Object.create(null);
  _maxListeners;
  static get defaultMaxListeners() {
    return defaultMaxListeners;
  }
  static set defaultMaxListeners(arg) {
    if (typeof arg !== "number" || arg < 0 || Number.isNaN(arg)) {
      throw new RangeError('The value of "defaultMaxListeners" is out of range. It must be a non-negative number. Received ' + arg + ".");
    }
    defaultMaxListeners = arg;
  }
  setMaxListeners(n) {
    if (typeof n !== "number" || n < 0 || Number.isNaN(n)) {
      throw new RangeError('The value of "n" is out of range. It must be a non-negative number. Received ' + n + ".");
    }
    this._maxListeners = n;
    return this;
  }
  getMaxListeners() {
    return _getMaxListeners(this);
  }
  emit(type, ...args) {
    if (!this._events[type] || this._events[type].length === 0) {
      return false;
    }
    if (type === "error") {
      let er;
      if (args.length > 0) {
        er = args[0];
      }
      if (er instanceof Error) {
        throw er;
      }
      const err = new Error("Unhandled error." + (er ? " (" + er.message + ")" : ""));
      err.context = er;
      throw err;
    }
    for (const _listener of this._events[type]) {
      (_listener.listener || _listener).apply(this, args);
    }
    return true;
  }
  addListener(type, listener) {
    return _addListener(this, type, listener, false);
  }
  on(type, listener) {
    return _addListener(this, type, listener, false);
  }
  prependListener(type, listener) {
    return _addListener(this, type, listener, true);
  }
  once(type, listener) {
    return this.on(type, _wrapOnce(this, type, listener));
  }
  prependOnceListener(type, listener) {
    return this.prependListener(type, _wrapOnce(this, type, listener));
  }
  removeListener(type, listener) {
    return _removeListener(this, type, listener);
  }
  off(type, listener) {
    return this.removeListener(type, listener);
  }
  removeAllListeners(type) {
    return _removeAllListeners(this, type);
  }
  listeners(type) {
    return _listeners(this, type, true);
  }
  rawListeners(type) {
    return _listeners(this, type, false);
  }
  listenerCount(type) {
    return this.rawListeners(type).length;
  }
  eventNames() {
    return Object.keys(this._events);
  }
}
exports.EventEmitter = EventEmitter;
function once(emitter, name) {
  return new Promise(function (resolve, reject) {
    function errorListener(err) {
      emitter.removeListener(name, resolver);
      reject(err);
    }
    function resolver() {
      if (typeof emitter.removeListener === "function") {
        emitter.removeListener("error", errorListener);
      }
      resolve(Array.prototype.slice.call(arguments));
    }
    _eventTargetAgnosticAddListener(emitter, name, resolver, {
      once: true
    });
    if (name !== "error") {
      _addErrorHandlerIfEventEmitter(emitter, errorListener, {
        once: true
      });
    }
  });
}
function _addListener(target, type, listener, prepend) {
  _checkListener(listener);
  if (target._events.newListener !== void 0) {
    target.emit("newListener", type, listener.listener || listener);
  }
  if (!target._events[type]) {
    target._events[type] = [];
  }
  if (prepend) {
    target._events[type].unshift(listener);
  } else {
    target._events[type].push(listener);
  }
  const maxListeners = _getMaxListeners(target);
  if (maxListeners > 0 && target._events[type].length > maxListeners && !target._events[type].warned) {
    target._events[type].warned = true;
    const warning = new Error(`[unenv] Possible EventEmitter memory leak detected. ${target._events[type].length} ${type} listeners added. Use emitter.setMaxListeners() to increase limit`);
    warning.name = "MaxListenersExceededWarning";
    warning.emitter = target;
    warning.type = type;
    warning.count = target._events[type]?.length;
    console.warn(warning);
  }
  return target;
}
function _removeListener(target, type, listener) {
  _checkListener(listener);
  if (!target._events[type] || target._events[type].length === 0) {
    return target;
  }
  const lenBeforeFilter = target._events[type].length;
  target._events[type] = target._events[type].filter(fn => fn !== listener);
  if (lenBeforeFilter === target._events[type].length) {
    return target;
  }
  if (target._events.removeListener) {
    target.emit("removeListener", type, listener.listener || listener);
  }
  if (target._events[type].length === 0) {
    delete target._events[type];
  }
  return target;
}
function _removeAllListeners(target, type) {
  if (!target._events[type] || target._events[type].length === 0) {
    return target;
  }
  if (target._events.removeListener) {
    for (const _listener of target._events[type]) {
      target.emit("removeListener", type, _listener.listener || _listener);
    }
  }
  delete target._events[type];
  return target;
}
function _wrapOnce(target, type, listener) {
  let fired = false;
  const wrapper = (...args) => {
    if (fired) {
      return;
    }
    target.removeListener(type, wrapper);
    fired = true;
    return args.length === 0 ? listener.call(target) : listener.apply(target, args);
  };
  wrapper.listener = listener;
  return wrapper;
}
function _getMaxListeners(target) {
  return target._maxListeners ?? EventEmitter.defaultMaxListeners;
}
function _listeners(target, type, unwrap) {
  let listeners = target._events[type];
  if (typeof listeners === "function") {
    listeners = [listeners];
  }
  return unwrap ? listeners.map(l => l.listener || l) : listeners;
}
function _checkListener(listener) {
  if (typeof listener !== "function") {
    throw new TypeError('The "listener" argument must be of type Function. Received type ' + typeof listener);
  }
}
function _addErrorHandlerIfEventEmitter(emitter, handler, flags) {
  if (typeof emitter.on === "function") {
    _eventTargetAgnosticAddListener(emitter, "error", handler, flags);
  }
}
function _eventTargetAgnosticAddListener(emitter, name, listener, flags) {
  if (typeof emitter.on === "function") {
    if (flags.once) {
      emitter.once(name, listener);
    } else {
      emitter.on(name, listener);
    }
  } else if (typeof emitter.addEventListener === "function") {
    emitter.addEventListener(name, listener);
  } else {
    throw new TypeError('The "emitter" argument must be of type EventEmitter. Received type ' + typeof emitter);
  }
}