From ca583ba98aaa6c6e19c353d0be085ab0ae0e6115 Mon Sep 17 00:00:00 2001
From: Codex <codex@noreply.local>
Date: Fri, 26 Jun 2026 13:38:22 +0000
Subject: [PATCH] fix: recover workbench session switchback hydration

---
 .../hwlab-node-web-observe-runner-source.ts   | 57 +++++++++++++++++--
 1 file changed, 51 insertions(+), 6 deletions(-)

diff --git a/scripts/src/hwlab-node-web-observe-runner-source.ts b/scripts/src/hwlab-node-web-observe-runner-source.ts
index c2a746ff..18e7bd92 100644
--- a/scripts/src/hwlab-node-web-observe-runner-source.ts
+++ b/scripts/src/hwlab-node-web-observe-runner-source.ts
@@ -1748,11 +1748,22 @@ async function switchAwayAndBack(command) {
   const switchAway = await clickSession(alternateSessionId);
   const awaySettle = await waitForWorkbenchSessionHydrated(page, alternateSessionId, { timeoutMs: 15000 });
   const away = awaySettle.snapshot ?? await workbenchSessionSnapshot();
-  const switchBack = await gotoTarget("/workbench/sessions/" + encodeURIComponent(canarySessionId));
-  const backSettle = await waitForWorkbenchSessionHydrated(page, canarySessionId, { timeoutMs: 15000 });
-  const after = backSettle.snapshot ?? await workbenchSessionSnapshot();
-  const routeOk = after?.routeSessionId === canarySessionId;
-  const activeOk = after?.activeSessionId === canarySessionId;
+  let switchBack = await gotoTarget("/workbench/sessions/" + encodeURIComponent(canarySessionId));
+  let backSettle = await waitForWorkbenchSessionHydrated(page, canarySessionId, { timeoutMs: 15000 });
+  let after = backSettle.snapshot ?? await workbenchSessionSnapshot();
+  let switchBackRecovery = null;
+  let routeOk = after?.routeSessionId === canarySessionId;
+  let activeOk = after?.activeSessionId === canarySessionId;
+  if (!routeOk || !activeOk) {
+    switchBackRecovery = await recoverControlPageSessionHydration(canarySessionId, backSettle);
+    if (switchBackRecovery?.ok === true) {
+      switchBack = { ...switchBack, recoveryApplied: true, recoveryNavigation: switchBackRecovery.navigation, valuesRedacted: true };
+      backSettle = switchBackRecovery.settle;
+      after = switchBackRecovery.snapshot ?? after;
+      routeOk = after?.routeSessionId === canarySessionId;
+      activeOk = after?.activeSessionId === canarySessionId;
+    }
+  }
   if (awaySettle.ok !== true) {
     const error = new Error("switchAwayAndBack did not settle on the alternate session");
     error.details = { canarySessionId, alternateSessionId, routeSessionId: away?.routeSessionId ?? null, activeSessionId: away?.activeSessionId ?? null, settle: awaySettle, pageId, valuesRedacted: true };
@@ -1760,7 +1771,7 @@ async function switchAwayAndBack(command) {
   }
   if (!routeOk || !activeOk) {
     const error = new Error("switchAwayAndBack did not return to the canary session");
-    error.details = { canarySessionId, alternateSessionId, routeSessionId: after?.routeSessionId ?? null, activeSessionId: after?.activeSessionId ?? null, settle: backSettle, pageId, valuesRedacted: true };
+    error.details = { canarySessionId, alternateSessionId, routeSessionId: after?.routeSessionId ?? null, activeSessionId: after?.activeSessionId ?? null, settle: backSettle, recovery: switchBackRecovery, pageId, valuesRedacted: true };
     throw error;
   }
   return {
@@ -1784,6 +1795,7 @@ async function switchAwayAndBack(command) {
     },
     switchBack,
     backSettle,
+    switchBackRecovery,
     routeSessionId: after?.routeSessionId ?? null,
     activeSessionId: after?.activeSessionId ?? null,
     routeOk,
@@ -1794,6 +1806,39 @@ async function switchAwayAndBack(command) {
   };
 }
 
+async function recoverControlPageSessionHydration(sessionId, previousSettle) {
+  const observerHydration = observerPage && !observerPage.isClosed()
+    ? await waitForWorkbenchSessionHydrated(observerPage, sessionId, { timeoutMs: 5000 })
+    : { ok: false, reason: "observer-page-unavailable", valuesRedacted: true };
+  if (observerHydration.ok !== true) {
+    return { ok: false, attempted: false, reason: "observer-session-not-hydrated", previousSettle, observerHydration, valuesRedacted: true };
+  }
+  await recreateControlPageForNavigation("switch-back-hydration-retry", 1);
+  const navigation = await gotoTarget("/workbench/sessions/" + encodeURIComponent(sessionId));
+  const settle = await waitForWorkbenchSessionHydrated(page, sessionId, { timeoutMs: 15000 });
+  const snapshot = settle.snapshot ?? await workbenchSessionSnapshot();
+  const routeOk = snapshot?.routeSessionId === sessionId;
+  const activeOk = snapshot?.activeSessionId === sessionId;
+  return {
+    ok: settle.ok === true && routeOk && activeOk,
+    attempted: true,
+    reason: settle.ok === true ? "control-page-recreated" : settle.reason || "control-session-hydration-retry-failed",
+    previousSettle,
+    observerHydration,
+    navigation,
+    settle,
+    snapshot: {
+      routeSessionId: snapshot?.routeSessionId ?? null,
+      activeSessionId: snapshot?.activeSessionId ?? null,
+      composerReady: snapshot?.composerReady === true,
+      messageCount: snapshot?.messageCount ?? null,
+      valuesRedacted: true,
+    },
+    pageId,
+    valuesRedacted: true,
+  };
+}
+
 async function assertSessionInvariant(command) {
   const beforeUrl = currentPageUrl();
   const snapshot = await workbenchSessionSnapshot();