From be98baa36c632fc4bff506ab92807166106a7d6e Mon Sep 17 00:00:00 2001
From: chris-wozniak <k8wozniak@gmail.com>
Date: Fri, 11 Sep 2026 23:34:37 -0400
Subject: [PATCH] Add once support to IStream

---
 typescript/src/types/client.ts                |  1 +
 .../tests/unit/stream/stream/events.test.ts   | 21 ++++++++++++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/typescript/src/types/client.ts b/typescript/src/types/client.ts
index 6836d14..d0ec323 100644
--- a/typescript/src/types/client.ts
+++ b/typescript/src/types/client.ts
@@ -10,6 +10,7 @@ export interface StreamOptions {
 
 export interface IStream {
   on(event: "report", listener: (report: Report) => void): this;
+  once(event: "report", listener: (report: Report) => void): this;
   on(event: "error", listener: (error: Error) => void): this;
   on(event: "disconnected", listener: () => void): this;
   on(
diff --git a/typescript/tests/unit/stream/stream/events.test.ts b/typescript/tests/unit/stream/stream/events.test.ts
index 0e82d75..4f60153 100644
--- a/typescript/tests/unit/stream/stream/events.test.ts
+++ b/typescript/tests/unit/stream/stream/events.test.ts
@@ -1,6 +1,6 @@
 import { describe, it, expect, beforeEach, jest } from "@jest/globals";
 import { Stream } from "../../../../src/stream";
-import { Config } from "../../../../src/types/client";
+import { Config, IStream } from "../../../../src/types/client";
 import { LogLevel } from "../../../../src/types/logger";
 import * as originDiscovery from "../../../../src/utils/origin-discovery";
 
@@ -93,6 +93,25 @@ describe("Stream - Event Re-emission", () => {
     expect(reconnectingSpy).toHaveBeenCalledWith(reconnectingInfo);
   });
 
+  it("supports one-time report listeners through IStream", () => {
+    const typedStream: IStream = stream;
+    const reportListener = jest.fn();
+    const report = {
+      feedID: "0x0003" + "1".repeat(60),
+      fullReport: "0x1234",
+      validFromTimestamp: 1,
+      observationsTimestamp: 2,
+    };
+
+    expect(typedStream.once("report", reportListener)).toBe(typedStream);
+
+    stream.emit("report", report);
+    stream.emit("report", report);
+
+    expect(reportListener).toHaveBeenCalledTimes(1);
+    expect(reportListener).toHaveBeenCalledWith(report);
+  });
+
   it("re-emits 'connection-lost' event exactly once per transition", async () => {
     const connectionLostSpy = jest.fn();
     stream.on("connection-lost", connectionLostSpy);