Ignore errors thrown by listeners

source/event-emitter.ts

@@ -158,7 +158,11 @@ export class EventEmitter<T extends EventMap> {
 
         // Emit the event to all listeners.
         listeners.forEach((entry) => {
+            try {
                 entry.wrappedListener(readonlyPayload);
+            } catch (error) {
+                console.error(error);
+            }
         });
 
         // Return true if there are listeners for the event, false otherwise.

test/event-emitter.test.ts

@@ -89,6 +89,24 @@ const testEventEmitterEmitReturnsTrueWithListeners = (): void => {
     expect(hasListeners).toBe(true);
 };
 
+/**
+ * Tests that EventEmitter.emit continues after a listener throws an error.
+ */
+const testEventEmitterEmitContinuesAfterListenerThrows = (): void => {
+    const emitter = new EventEmitter<TestEvents>();
+    const secondListener = vi.fn();
+
+    emitter.on('message', (): void => {
+        throw new Error('listener failure');
+    });
+    emitter.on('message', secondListener);
+
+    emitter.emit('message', 'hello');
+
+    expect(secondListener).toHaveBeenCalledOnce();
+    expect(secondListener).toHaveBeenCalledWith('hello');
+};
+
 /**
  * Tests that emitted events cannot be mutated.
  */
@@ -666,6 +684,7 @@ const runTests = async (): Promise<void> => {
     test('EventEmitter: only calls listeners for the emitted event type', testEventEmitterCallsOnlyMatchingListeners);
     test('EventEmitter: returns false when emitting with no listeners', testEventEmitterEmitReturnsFalseWithNoListeners);
     test('EventEmitter: returns true when emitting with listeners', testEventEmitterEmitReturnsTrueWithListeners);
+    test('EventEmitter: continues after a listener throws an error', testEventEmitterEmitContinuesAfterListenerThrows);
     test('EventEmitter: emitted events cannot be mutated', testEventEmitterEmittedEventsCannotBeMutated);
     test('EventEmitter: stops calling a listener after its off callback is invoked', testEventEmitterOffCallbackRemovesListener);
     test('EventEmitter: removes a listener when off is called with the same reference', testEventEmitterOffRemovesListenerByReference);