@types/node/events.d.ts

declare module 'events' {
    interface EventEmitterOptions {
        /**
         * Enables automatic capturing of promise rejection.
         */
        captureRejections?: boolean;
    }

    interface NodeEventTarget {
        once(event: string | symbol, listener: (...args: any[]) => void): this;
    }

    interface DOMEventTarget {
        addEventListener(event: string, listener: (...args: any[]) => void, opts?: { once: boolean }): any;
    }

    interface StaticEventEmitterOptions {
        signal?: AbortSignal;
    }

    interface EventEmitter extends NodeJS.EventEmitter {}
    class EventEmitter {
        constructor(options?: EventEmitterOptions);

        static once(emitter: NodeEventTarget, event: string | symbol, options?: StaticEventEmitterOptions): Promise<any[]>;
        static once(emitter: DOMEventTarget, event: string, options?: StaticEventEmitterOptions): Promise<any[]>;
        static on(emitter: NodeJS.EventEmitter, event: string, options?: StaticEventEmitterOptions): AsyncIterableIterator<any>;

        /** @deprecated since v4.0.0 */
        static listenerCount(emitter: NodeJS.EventEmitter, event: string | symbol): number;
        /**
         * Returns a list listener for a specific emitter event name.
         */
        static getEventListener(emitter: DOMEventTarget | NodeJS.EventEmitter, name: string | symbol): Function[];

        /**
         * This symbol shall be used to install a listener for only monitoring `'error'`
         * events. Listeners installed using this symbol are called before the regular
         * `'error'` listeners are called.
         *
         * Installing a listener using this symbol does not change the behavior once an
         * `'error'` event is emitted, therefore the process will still crash if no
         * regular `'error'` listener is installed.
         */
        static readonly errorMonitor: unique symbol;
        static readonly captureRejectionSymbol: unique symbol;

        /**
         * Sets or gets the default captureRejection value for all emitters.
         */
        // TODO: These should be described using static getter/setter pairs:
        static captureRejections: boolean;
        static defaultMaxListeners: number;
    }

    import internal = require('events');
    namespace EventEmitter {
        // Should just be `export { EventEmitter }`, but that doesn't work in TypeScript 3.4
        export { internal as EventEmitter };

        export interface Abortable {
            /**
             * When provided the corresponding `AbortController` can be used to cancel an asynchronous action.
             */
            signal?: AbortSignal;
        }
    }

    global {
        namespace NodeJS {
            interface EventEmitter {
                addListener(event: string | symbol, listener: (...args: any[]) => void): this;
                on(event: string | symbol, listener: (...args: any[]) => void): this;
                once(event: string | symbol, listener: (...args: any[]) => void): this;
                removeListener(event: string | symbol, listener: (...args: any[]) => void): this;
                off(event: string | symbol, listener: (...args: any[]) => void): this;
                removeAllListeners(event?: string | symbol): this;
                setMaxListeners(n: number): this;
                getMaxListeners(): number;
                listeners(event: string | symbol): Function[];
                rawListeners(event: string | symbol): Function[];
                emit(event: string | symbol, ...args: any[]): boolean;
                listenerCount(event: string | symbol): number;
                // Added in Node 6...
                prependListener(event: string | symbol, listener: (...args: any[]) => void): this;
                prependOnceListener(event: string | symbol, listener: (...args: any[]) => void): this;
                eventNames(): Array<string | symbol>;
            }
        }
    }

    export = EventEmitter;
}