feat: add emitted helper

README.md

@@ -72,6 +72,15 @@ Unregister an event listener. Returns true on success and false when the event l
 off(eventName, listener) => boolean
 ```
 
+### `Houk.awaitEvent`
+
+Returns a promise that will resolve, once the given event was triggered.
+
+```ts
+await houk.awaitEvent('myEvent');
+console.log('myEvent was emitted');
+```
+
 ### `Houk.emit`
 
 Only available to deriving classes. Trigger all listeners of a particular event. `...args` will be passed along to the listeners.

src/__tests__/emitted.test.ts

@@ -0,0 +1,27 @@
+import Houk from '..';
+
+describe('HoukClass', () => {
+	it('emits to listeners', async () => {
+		expect.assertions(2);
+
+		class Test extends Houk<{
+			event1: [something: number];
+		}> {
+			public fire(): void {
+				void this.emit('event1', 4);
+			}
+		}
+
+		let called = false;
+		const t = new Test();
+
+		const promise = t.awaitEvent('event1').then(() => {
+			called = true;
+		});
+		expect(called).toBe(false);
+		t.fire();
+
+		await promise;
+		expect(called).toBe(true);
+	});
+});

src/index.ts

@@ -40,6 +40,18 @@ export default abstract class Houk<Events extends EventTypes> {
 		return this.getListeners(event).delete(fn);
 	}
 
+	/**
+	 * Returns a promise that will resolve once the given event has been triggered.
+	 * @param event The event name
+	 */
+	public async awaitEvent<EventName extends keyof Events>(
+		event: EventName
+	): Promise<void> {
+		return new Promise((resolve: () => void) => {
+			this.on(event, resolve, true);
+		});
+	}
+
 	/**
 	 Emit an event to all listeners. Listeners will be called in the order of registration. All listeners run at once.abs
 	* @returns The promise will be resolved once all listener functions have returned a resolved promise.