emrg: switching sessions never refuses on a running turn

Agent.md

@@ -54,8 +54,8 @@ What EMRG does today — capability statements, not a changelog.
 One line per command: what it answers. Run the daemon in the foreground with `python -m emrg`.
 
 - Python: `uv run pytest tests/ -v` — the number is **measured, never stored**: `uv run --no-sync python3 scripts/check-doc-count.py --measure`. Import check: `uv run python -c "from emrg.client.app import run_client"`
-GUI: `cd emrg/gui && npm test` (168: 100 daemon_client + 20 conn-manager + 7 integration + 7 nav-policy + 7 gui-state + 9 build-config + 11 boot-contract + 3 preload-api + 2 theme-guard + 2 image-hash) — syntax: `node --check main.js preload.js daemon_client.js`
-Renderer: `cd emrg/gui/renderer && npm run typecheck && npm test` (752: 5 snapshot-store + 13 utils + 3 ErrorBoundary + 2 App smoke + 11 commands + 4 copywriting + 11 i18n + 21 markdown + 29 transcript + 28 TranscriptView + 22 history + 25 historyReplay + 40 composer + 75 Composer + 6 LinkDialog + 16 sidebar + 18 Sidebar + 9 fileTree + 9 FileTree + 17 resultPanel + 8 ResultPanel + 27 workspaceView + 13 WorkspaceView + 10 dialog + 6 Dialog + 9 ConfirmDialog + 9 RenameDialog + 12 dialogLists + 3 HelpDialog + 9 MemoryDialog + 8 SkillsDialog + 8 openSession + 6 WelcomeDialog + 9 OpenSessionDialog + 7 NewSessionDialog + 7 rewind + 8 RewindDialog + 7 GithubDeviceDialog + 59 daemonBridge + 9 DaemonBridgeProvider + 50 Shell + 25 DialogHost + 26 SettingsPanel + 18 TaskFormDialog + 5 RantDialog + 8 vendorMarkdown + 6 ApprovalDialog + 16 SandboxRootsDialog)
+GUI: `cd emrg/gui && npm test` (172: 100 daemon_client + 20 conn-manager + 7 integration + 7 nav-policy + 7 gui-state + 9 build-config + 11 boot-contract + 3 preload-api + 2 theme-guard + 2 image-hash + 4 switch-session) — syntax: `node --check main.js preload.js daemon_client.js`
+Renderer: `cd emrg/gui/renderer && npm run typecheck && npm test` (754: 5 snapshot-store + 13 utils + 3 ErrorBoundary + 2 App smoke + 11 commands + 4 copywriting + 11 i18n + 21 markdown + 29 transcript + 28 TranscriptView + 22 history + 25 historyReplay + 40 composer + 75 Composer + 6 LinkDialog + 16 sidebar + 18 Sidebar + 9 fileTree + 9 FileTree + 17 resultPanel + 8 ResultPanel + 27 workspaceView + 13 WorkspaceView + 10 dialog + 6 Dialog + 9 ConfirmDialog + 9 RenameDialog + 12 dialogLists + 3 HelpDialog + 9 MemoryDialog + 8 SkillsDialog + 8 openSession + 6 WelcomeDialog + 9 OpenSessionDialog + 7 NewSessionDialog + 7 rewind + 8 RewindDialog + 7 GithubDeviceDialog + 59 daemonBridge + 9 DaemonBridgeProvider + 52 Shell + 25 DialogHost + 26 SettingsPanel + 18 TaskFormDialog + 5 RantDialog + 8 vendorMarkdown + 6 ApprovalDialog + 16 SandboxRootsDialog)
 - CI: pytest on ubuntu **and windows-2025**, the GUI suites, and an actionlint gate over `.github/workflows/`; re-trigger a dropped push with `scripts/re-trigger-ci.sh <branch>`, never an empty commit
 - Merge gates, run before merging — each asks what no other gate asks: `uv run --no-sync python3 scripts/check-vote-count.py` (approvals still valid) · `scripts/check-pr-base.py` (base reaches master) · `scripts/check-merge-freshness.py` (that green CI is about the landing tree) · `scripts/check-merge-order.py` (dirt and what it lands) · `scripts/check-merge-landing-diff.py` (what the landing changes) · `scripts/check-merge-pairs.py` / `scripts/check-merge-sequence.py` (a pair, or a whole order) · `scripts/check-merge-tree-health.py` (the merged tree passes one guard) · `scripts/check-merge-plan-suite.py` (the plan's final tree passes the suite) — all under `uv run --no-sync python3`
 - Post-merge audit: `uv run --no-sync python3 scripts/check-merge-landed.py <N>` (did the merge land a tree its reviews named)
@@ -73,7 +73,7 @@ Every guard that reads a working tree names it before its verdict; a question it
 
 ## Packaging
 
-Only `icon.svg` is committed; the generated icon products are gitignored and CI builds them. A local build runs `bash packaging/gen-assets.sh` first — idempotent, and `.icns` needs macOS `iconutil`.
+Only `icon.svg` is committed; generated icon products are gitignored and CI builds them (`bash packaging/gen-assets.sh` locally first; `.icns` needs macOS `iconutil`).
 
 ## Configuration
 

emrg/gui/main.js

@@ -584,11 +584,10 @@ vision = false
         logger.warn(`[gui:switch] REJECT too many open sessions (${openSessions.size}/${DEFAULT_CAP}) sid=${sessionId}`);
         throw new Error(`too many open sessions (${DEFAULT_CAP}) — close some first`);
       }
-      // G65：自有流运行中禁止切会话（每连接独立锁，查当前激活连接）
-      if (connManager?.get(currentSessionId)?.ownStream) {
-        logger.warn(`[gui:switch] REJECT own stream in progress (sid=${currentSessionId})`);
-        throw new Error("stream in progress — cannot switch");
-      }
+      // 切会话不再因「当前会话仍在流式」而拒绝（issue #2637）：切走只打开/复用**目标**
+      // 会话的连接，旧连接原样保留（见下方 openSession 之后的 P4 注释），所以一个正在
+      // 生成的回合不受切换影响。真正会切断回合的是主动关闭——`ConnManager.close()`
+      // 先发 cancel 再断 ws，那条路径不变。
       const prevSid = currentSessionId;
       logger.info(`[gui:switch] prevSid=${prevSid} → target=${sessionId}, openSessions.size=${openSessions.size}`);
       // G110：切会话清空旧连接分组缓存（含 timer），防广播"幽灵"残留

emrg/gui/renderer/src/components/Shell.test.tsx

@@ -685,6 +685,37 @@ describe("Shell (Batch 5 slice 3 chat wiring)", () => {
     expect(screen.queryByTestId("panel-tasks")).not.toBeInTheDocument();
   });
 
+  it("切换被拒（issue #2637）：任务面板原地不动，拒绝出现在人操作的面板上，不写进没人看的转录", async () => {
+    const m = mockEmrg();
+    m.switchSession.mockRejectedValueOnce(new Error("boom-guard"));
+    render(wrapper(<Shell />));
+    await waitFor(() => expect(screen.getByTestId("composer")).toBeInTheDocument());
+    fireEvent.click(screen.getByTestId("nav-tasks"));
+    await waitFor(() => expect(screen.getByTestId("task-row")).toBeInTheDocument());
+    fireEvent.click(screen.getByTitle("Open session"));
+    // 拒绝可见：横幅就在任务面板上方
+    const banner = await screen.findByTestId("switch-error");
+    expect(banner).toHaveTextContent("boom-guard");
+    // 人没有被搬走：仍在任务面板，会话视图没有被切换过去
+    expect(screen.getByTestId("panel-tasks")).toBeInTheDocument();
+    expect(screen.queryByTestId("composer")).not.toBeInTheDocument();
+  });
+
+  it("切换被拒后再次成功 → 横幅退场并进入会话视图（issue #2637）", async () => {
+    const m = mockEmrg();
+    m.switchSession.mockRejectedValueOnce(new Error("boom-guard"));
+    render(wrapper(<Shell />));
+    await waitFor(() => expect(screen.getByTestId("composer")).toBeInTheDocument());
+    fireEvent.click(screen.getByTestId("nav-tasks"));
+    await waitFor(() => expect(screen.getByTestId("task-row")).toBeInTheDocument());
+    fireEvent.click(screen.getByTitle("Open session"));
+    await screen.findByTestId("switch-error");
+    // 第二次点击：mock 已回落到默认 resolve
+    fireEvent.click(screen.getByTitle("Open session"));
+    await waitFor(() => expect(screen.getByTestId("composer")).toBeInTheDocument());
+    expect(screen.queryByTestId("switch-error")).not.toBeInTheDocument();
+  });
+
   it("进入 Rant 面板 → 加载 listRants 并渲染 rant 行", async () => {
     const m = mockEmrg();
     render(wrapper(<Shell />));

emrg/gui/renderer/src/components/Shell.tsx

@@ -130,6 +130,9 @@ export function Shell() {
   const [rants, setRants] = useState<RantRec[]>([]);
   const [projectSessions, setAgentSessions] = useState<SessionRow[] | null>(null);
   const [projectSessionsError, setAgentSessionsError] = useState<string | null>(null);
+  // 切会话被拒时的可见提示（issue #2637）：拒绝必须落在人操作的那个面板上，
+  // 而不是一个不在屏幕上的转录或一个未处理的 Promise。
+  const [switchError, setSwitchError] = useState<string | null>(null);
   const [dialogState, dispatch] = useReducer(dialogReducer, initialDialogState);
   // Batch 5 slice 8：任务表单 + Rant 对话框（vanilla openTaskForm/openRantForm 语义）
   const [taskForm, setTaskForm] = useState<{ task: TaskRec | null } | null>(null);
@@ -322,7 +325,16 @@ export function Shell() {
 
   async function selectProjectSession(p: AgentRec, sid: string) {
     const b = wsBridge();
-    if (b?.switchSession) await b.switchSession({ sessionId: sid });
+    if (!b?.switchSession) return;
+    try {
+      await b.switchSession({ sessionId: sid });
+    } catch (e) {
+      // 切换失败：人没有离开当前视图，所以拒绝要出现在**这里**（issue #2637）——
+      // 以前这一行没有 try，拒绝变成未处理的 Promise rejection，点一下像没反应。
+      setSwitchError((e as Error)?.message ?? String(e));
+      return;
+    }
+    setSwitchError(null);
     setActiveSid(sid);
     setActiveView("sessions");
     void loadHistory(sid);
@@ -335,14 +347,14 @@ export function Shell() {
     if (!b?.switchSession) return;
     try {
       await b.switchSession({ sessionId: task.session_id, projectPath: task.agent_path });
+      setSwitchError(null);
       setActiveSid(task.session_id);
       setActiveView("sessions");
       void loadHistory(task.session_id);
     } catch (e) {
-      transcript.addSystemMessage(
-        t("openSession.loadFailed", { msg: (e as Error)?.message ?? String(e) }),
-        activeSid,
-      );
+      // 以前这条拒绝被写进 `activeSid` 的会话记录，而人正看着任务面板 —— 消息落在
+      // 一个不在屏幕上的转录里。面板视图上方的横幅才是人操作的地方（issue #2637）。
+      setSwitchError((e as Error)?.message ?? String(e));
     }
   }
 
@@ -452,6 +464,8 @@ export function Shell() {
   /** 工作区视图切换（vanilla app.js switchView 语义）：
    *  点当前面板 → toggle 回会话视图；点其他面板 → 切换；点 sessions → 回会话视图 */
   function switchView(view: SidebarViewId): void {
+    // 换视图即离开那次失败的操作现场，提示随之退场（issue #2637）
+    setSwitchError(null);
     if (view === "sessions") {
       setActiveView("sessions");
       return;
@@ -795,28 +809,35 @@ export function Shell() {
         </aside>
         <main className="react-shell-main" data-testid="react-shell-main">
           {isPanelView ? (
-            <WorkspaceView
-              activeView={activeView}
-              onSwitch={switchView}
-              agents={agents}
-              tasks={tasks}
-              rants={rants}
-              projectSessions={projectSessions}
-              projectSessionsError={projectSessionsError}
-              currentSid={activeSid}
-              version={appState.currentVersion}
-              evolutionCount={appState.evolutionCount}
-              onViewAgentSessions={(p) => void loadProjectSessions(p)}
-              onSelectAgentSession={(p, sid) => void selectProjectSession(p, sid)}
-              onAddAgent={() => void addProject()}
-              onDeleteAgent={deleteAgent}
-              onTriggerTask={(task) => void triggerTask(task)}
-              onOpenSessionTask={(task) => void openTaskSession(task)}
-              onEditTask={(task) => void openTaskForm(task)}
-              onDeleteTask={(task) => deleteTask(task)}
-              onNewRant={() => void newRant()}
-              renderer={mdRenderer}
-            />
+            <>
+              {switchError ? (
+                <div className="switch-banner" role="alert" data-testid="switch-error">
+                  {t("app.switchFailed", { msg: switchError })}
+                </div>
+              ) : null}
+              <WorkspaceView
+                activeView={activeView}
+                onSwitch={switchView}
+                agents={agents}
+                tasks={tasks}
+                rants={rants}
+                projectSessions={projectSessions}
+                projectSessionsError={projectSessionsError}
+                currentSid={activeSid}
+                version={appState.currentVersion}
+                evolutionCount={appState.evolutionCount}
+                onViewAgentSessions={(p) => void loadProjectSessions(p)}
+                onSelectAgentSession={(p, sid) => void selectProjectSession(p, sid)}
+                onAddAgent={() => void addProject()}
+                onDeleteAgent={deleteAgent}
+                onTriggerTask={(task) => void triggerTask(task)}
+                onOpenSessionTask={(task) => void openTaskSession(task)}
+                onEditTask={(task) => void openTaskForm(task)}
+                onDeleteTask={(task) => deleteTask(task)}
+                onNewRant={() => void newRant()}
+                renderer={mdRenderer}
+              />
+            </>
           ) : (
             <>
               {disconnected ? (

emrg/gui/renderer/src/shell.css

@@ -168,7 +168,8 @@
   color: var(--text-1);
 }
 
-.react-shell-main .conn-banner {
+.react-shell-main .conn-banner,
+.react-shell-main .switch-banner {
   padding: 8px 16px;
   background: var(--amber-soft);
   color: var(--amber);

emrg/gui/test/switch-session.test.js

@@ -0,0 +1,81 @@
+"use strict";
+/**
+ * switch-session.test.js — 切会话永不因「当前会话仍在流式」被拒（issue #2637）。
+ *
+ * 守卫的对象是 `main.js` 里 `emrg:switchSession` 的处理块：它以前在打开任何连接之前，
+ * 用 `connManager.get(currentSessionId).ownStream` 拒绝切换。那条拒绝来自「切会话会关掉
+ * 旧连接」的年代；切走早已不再关闭旧连接（打开目标会话的连接，旧连接原样保留），所以它
+ * 只拒绝、不保护 —— 一个在会话 A 上生成的回合，与把窗口移到 B 无关。
+ *
+ * 断言两块，一正一反：
+ * - 该处理块**不再**读 `ownStream`；
+ * - 该处理块**仍然**带另外三条拒绝（非法 session_id / 非法 agent path / 20 条上限），
+ *   所以「区域取空 ⇒ 断言通过」这种空过法在这里读作失败。
+ *
+ * 另一半（`ConnManager.close()` 对在忙连接先 cancel 再 close）不在这里断言：它是行为，
+ * 不是源码形状，`conn-manager.test.js` 的「P6 close: 在忙连接（ownStream）先 cancel 再
+ * close」用真实帧把它测住了。一处规则一处断言。
+ */
+const { test } = require("node:test");
+const assert = require("node:assert");
+const fs = require("node:fs");
+const path = require("node:path");
+
+const MAIN_JS = path.join(__dirname, "..", "main.js");
+const source = fs.readFileSync(MAIN_JS, "utf8");
+
+/**
+ * 从 `ipcMain.handle("emrg:<name>"` 起，到**下一个** `ipcMain.handle(` 为止的处理块。
+ *
+ * 上界用下一个处理块而不是「文件末尾」：`split(marker)[0]` 会一路铺到 EOF，于是区域外的
+ * 任何一处命中都被读成区域内命中，反之区域内的改动也可能被更大的区域掩盖。
+ */
+function handlerRegion(src, name) {
+  const marker = `ipcMain.handle("emrg:${name}"`;
+  const start = src.indexOf(marker);
+  assert.notStrictEqual(start, -1, `main.js must register ${marker}`);
+  const rest = src.slice(start + marker.length);
+  const next = rest.indexOf("ipcMain.handle(");
+  return next === -1 ? rest : rest.slice(0, next);
+}
+
+test("emrg:switchSession 的处理块不再读 ownStream（issue #2637）", () => {
+  const region = handlerRegion(source, "switchSession");
+  assert.ok(region.length > 500, `the switch region must be the real handler, got ${region.length} chars`);
+  assert.ok(
+    !region.includes("ownStream"),
+    "the switch handler must not refuse on ownStream any more: switching leaves the previous " +
+      "connection open, so a running turn is unaffected by moving the window to another session",
+  );
+});
+
+test("switchSession 的其余三条拒绝仍在（区域是真的处理块，不是空片）", () => {
+  const region = handlerRegion(source, "switchSession");
+  assert.ok(region.includes('throw new Error("invalid session_id")'), "the session_id refusal must stay");
+  assert.ok(region.includes('throw new Error("invalid agent path")'), "the agent-path refusal must stay");
+  assert.ok(region.includes("too many open sessions"), "the open-session cap refusal must stay");
+});
+
+test("switchSession 不关闭它离开的那个连接（去掉拒绝的那一步所依赖的事实）", () => {
+  // 上一条断言（不再因 ownStream 拒绝）只有在「切走不关闭旧连接」成立时才是安全的：
+  // 旧连接若被关，`ConnManager.close()` 会先给在忙的连接发 cancel（见 conn-manager.test.js），
+  // 那个正在生成的回合就真的被切换掐断了。所以这里把那条事实也钉住。
+  // 允许的 close 只有一处：会话不存在时关掉**目标**那条失败连接（catch 里的防御），
+  // 所以断言的对象是「离开的那个 sid」——`close(prevSid` 一律不许出现。
+  const region = handlerRegion(source, "switchSession");
+  assert.ok(!/close\(\s*prevSid/.test(region), "switching must not close the connection it leaves");
+  assert.ok(
+    region.includes("clearGroups()"),
+    "the previous session's group cache is cleared (a cache, not the connection) — if this call " +
+      "moved, re-read which of the two the switch path still does",
+  );
+});
+
+test("区域取法本身会切分（换一个处理块取到的是另一块）", () => {
+  // 仪器的控制：同一份源码取两个不同处理块，必须得到不同文本，且各自带自己的标记。
+  const switchRegion = handlerRegion(source, "switchSession");
+  const closeRegion = handlerRegion(source, "closeSession");
+  assert.notStrictEqual(switchRegion, closeRegion);
+  assert.ok(closeRegion.includes("closeSession("), "the closeSession region must carry its own body");
+  assert.ok(!switchRegion.includes("closeSession("), "the switch region must not run into the next handler");
+});