add native event emitter test

1 files changed, 17 insertions, 0 deletions

diff --git a/test/js/node/events/native-event-emitter.test.ts b/test/js/node/events/native-event-emitter.test.ts
new file mode 100644
index 000000000..b82e484b8
--- /dev/null
+++ b/test/js/node/events/native-event-emitter.test.ts
@@ -0,0 +1,17 @@
+import { describe, test, expect } from "bun:test";
+import stream from "stream";
+
+describe("Native EventEmitter", () => {
+  test("newListener fires before the listener is actually added", () => {
+    const emitter = new stream.Stream(); // stream extends native EventEmitters
+    let called = false;
+    emitter.on("newListener", (event: any, listener: any) => {
+      expect(event).toBe("foo");
+      expect(emitter.listeners("foo")).toEqual([]);
+      expect(emitter.listenerCount("foo")).toEqual(0);
+      called = true;
+    });
+    emitter.on("foo", () => {});
+    expect(called).toBe(true);
+  });
+});