import EventEmitter from 'events'; export class SaferEmitter extends EventEmitter { emit(type: string, ...args: unknown[]) { let doError = type === 'error'; let events = (this as any)._events; if (events !== undefined) doError = doError && events.error === undefined; else if (!doError) return false; // If there is no 'error' event listener then throw. if (doError) { let er; if (args.length > 0) er = args[0]; if (er instanceof Error) { // Note: The comments on the `throw` lines are intentional, they show // up in Node's output if this results in an unhandled exception. throw er; // Unhandled 'error' event } // At least give some kind of context to the user let err = new Error('Unhandled error.' + (er ? ' (' + (er as any).message + ')' : '')); (err as any).context = er; throw err; // Unhandled 'error' event } let handler = events[type]; if (handler === undefined) return false; if (typeof handler === 'function') { try { Reflect.apply(handler, this, args); } catch (error) { events[type] = undefined; } } else { let listeners = [...handler]; listeners .filter((e) => { try { e.call; } catch (error) { return false; } return true; }) .forEach((listener) => { try { Reflect.apply(listener, this, args); } catch (error) { console.error(error); debugger; } }); } return true; } }