From 1e87f6bf703dd3571bb719900e29a160d2e911a7 Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Fri, 1 May 2026 00:44:11 +0100
Subject: [PATCH] fix(qa-lab): preserve gateway log offset order

---
 extensions/qa-lab/src/gateway-child.test.ts | 17 +++++++++++++++++
 extensions/qa-lab/src/gateway-child.ts      | 21 +++++++++++++++++++--
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/extensions/qa-lab/src/gateway-child.test.ts b/extensions/qa-lab/src/gateway-child.test.ts
index 2036bb064ef..f05082c54ba 100644
--- a/extensions/qa-lab/src/gateway-child.test.ts
+++ b/extensions/qa-lab/src/gateway-child.test.ts
@@ -344,6 +344,23 @@ describe("buildQaRuntimeEnv", () => {
     await expect(wait).resolves.toBeUndefined();
   });
 
+  it("keeps restart offsets stable after stderr output", async () => {
+    const output = __testing.createQaGatewayChildLogCollector();
+    output.push(Buffer.from("gateway ready\n"));
+    output.push(Buffer.from("stderr warning\n"));
+    const offset = output.text().length;
+    const wait = __testing.waitForQaGatewayRestartBoundary({
+      logs: () => output.text(),
+      offset,
+      pollMs: 1,
+      timeoutMs: 100,
+    });
+
+    output.push(Buffer.from("signal SIGUSR1 received\nrestart mode: in-process restart\n"));
+
+    await expect(wait).resolves.toBeUndefined();
+  });
+
   it("times out when a SIGUSR1 restart never reaches the boundary", async () => {
     await expect(
       __testing.waitForQaGatewayRestartBoundary({
diff --git a/extensions/qa-lab/src/gateway-child.ts b/extensions/qa-lab/src/gateway-child.ts
index a62e0f2ef16..238250504ac 100644
--- a/extensions/qa-lab/src/gateway-child.ts
+++ b/extensions/qa-lab/src/gateway-child.ts
@@ -247,6 +247,18 @@ function isRetryableGatewayCallError(details: string): boolean {
   );
 }
 
+function createQaGatewayChildLogCollector() {
+  const chunks: Buffer[] = [];
+  return {
+    push(chunk: Buffer) {
+      chunks.push(Buffer.from(chunk));
+    },
+    text() {
+      return Buffer.concat(chunks).toString("utf8").trim();
+    },
+  };
+}
+
 async function fetchLocalGatewayHealth(params: {
   baseUrl: string;
   healthPath: "/readyz" | "/healthz";
@@ -307,6 +319,7 @@ export const __testing = {
   resolveQaOwnerPluginIdsForProviderIds,
   resolveQaBundledPluginSourceDir,
   resolveQaRuntimeHostVersion,
+  createQaGatewayChildLogCollector,
   createQaBundledPluginsDir,
   stopQaGatewayChildProcessTree,
 };
@@ -574,13 +587,13 @@ export async function startQaGatewayChild(params: {
   };
   const stdout: Buffer[] = [];
   const stderr: Buffer[] = [];
+  const output = createQaGatewayChildLogCollector();
   const stdoutLogPath = path.join(tempRoot, "gateway.stdout.log");
   const stderrLogPath = path.join(tempRoot, "gateway.stderr.log");
   const stdoutLog = createWriteStream(stdoutLogPath, { flags: "a" });
   const stderrLog = createWriteStream(stderrLogPath, { flags: "a" });
 
-  const logs = () =>
-    `${Buffer.concat(stdout).toString("utf8")}\n${Buffer.concat(stderr).toString("utf8")}`.trim();
+  const logs = () => output.text();
   const keepTemp = process.env.OPENCLAW_QA_KEEP_TEMP === "1";
   let gatewayPort = 0;
   let baseUrl = "";
@@ -667,11 +680,13 @@ export async function startQaGatewayChild(params: {
       attemptChild.stdout.on("data", (chunk) => {
         const buffer = Buffer.from(chunk);
         stdout.push(buffer);
+        output.push(buffer);
         stdoutLog.write(buffer);
       });
       attemptChild.stderr.on("data", (chunk) => {
         const buffer = Buffer.from(chunk);
         stderr.push(buffer);
+        output.push(buffer);
         stderrLog.write(buffer);
       });
       child = attemptChild;
@@ -760,11 +775,13 @@ export async function startQaGatewayChild(params: {
       nextChild.stdout.on("data", (chunk) => {
         const buffer = Buffer.from(chunk);
         stdout.push(buffer);
+        output.push(buffer);
         stdoutLog.write(buffer);
       });
       nextChild.stderr.on("data", (chunk) => {
         const buffer = Buffer.from(chunk);
         stderr.push(buffer);
+        output.push(buffer);
         stderrLog.write(buffer);
       });