emrg: the switch path in both directions

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` (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` (764: 5 snapshot-store + 13 utils + 3 ErrorBoundary + 2 App smoke + 11 commands + 4 copywriting + 11 i18n + 21 markdown + 34 transcript + 32 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 + 60 daemonBridge + 9 DaemonBridgeProvider + 52 Shell + 25 DialogHost + 26 SettingsPanel + 18 TaskFormDialog + 5 RantDialog + 8 vendorMarkdown + 6 ApprovalDialog + 16 SandboxRootsDialog)
+GUI: `cd emrg/gui && npm test` (175: 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 + 7 switch-session) — syntax: `node --check main.js preload.js daemon_client.js`
+Renderer: `cd emrg/gui/renderer && npm run typecheck && npm test` (765: 5 snapshot-store + 13 utils + 3 ErrorBoundary + 2 App smoke + 11 commands + 4 copywriting + 11 i18n + 21 markdown + 34 transcript + 32 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 + 60 daemonBridge + 9 DaemonBridgeProvider + 53 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)

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

@@ -762,6 +762,32 @@ describe("Shell (Batch 5 slice 3 chat wiring)", () => {
     expect(screen.getByTestId("agent-session-row")).toHaveTextContent("会话一");
   });
 
+  it("项目会话切换被拒（issue #2771）：拒绝出现在人操作的项目面板上，人没有被搬走", async () => {
+    // 侧栏之外的第二条切换路径：项目面板的会话子视图（agent-session-row → onSelectAgentSession
+    // → selectProjectSession）。此前那条 catch 没有任何测试走过 —— 删掉它整套仍然 52 passed，
+    // 而「切换被拒时把拒绝显示给点的人」这句话就只剩另一半被证明。
+    const m = mockEmrg();
+    m.listAgents.mockResolvedValue([{ name: "p1", path: "/p/p1" }]);
+    (window as unknown as { emrg: { listAgentSessions?: unknown } }).emrg.listAgentSessions =
+      vi.fn().mockResolvedValue({ sessions: [{ session_id: "s1", title: "会话一" }] });
+    m.switchSession.mockRejectedValueOnce(new Error("boom-project"));
+    render(wrapper(<Shell />));
+    await waitFor(() => expect(screen.getByTestId("composer")).toBeInTheDocument());
+    fireEvent.click(screen.getByTestId("nav-agents"));
+    await waitFor(() => expect(screen.getByTestId("agent-row")).toBeInTheDocument());
+    const row = screen.getByTestId("agent-row");
+    fireEvent.click(row.querySelector('button[title="Sessions"]') as HTMLButtonElement);
+    await waitFor(() => expect(screen.getByTestId("agent-session-row")).toBeInTheDocument());
+    // 点那一行 —— 这一击此前在整套测试里从未发生
+    fireEvent.click(screen.getByTestId("agent-session-row"));
+    // 拒绝可见：横幅带 daemon 交来的消息
+    const banner = await screen.findByTestId("switch-error");
+    expect(banner).toHaveTextContent("boom-project");
+    // 人没有被搬走：仍在项目面板，会话视图没有被切过去
+    expect(screen.getByTestId("panel-agents")).toBeInTheDocument();
+    expect(screen.queryByTestId("composer")).not.toBeInTheDocument();
+  });
+
   // ── Batch 5 slice 8：任务表单 + Rant 对话框接线 ──
 
   it("任务面板激活时每 5s 轮询 listTasks（vanilla startTaskPoll 语义）", async () => {

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

@@ -39,11 +39,48 @@ function handlerRegion(src, name) {
   return next === -1 ? rest : rest.slice(0, next);
 }
 
+/**
+ * 把 `//` 与块注释从一段源码里剥掉（issue #2771）。
+ *
+ * 守卫问的是「这段处理块里还有没有**代码**读这个名字」，而子串匹配回答的是「这一段正文里还
+ * 有没有这串字符」。两者差在注释上：只点名这个名字、一行代码都没读它的注释会被读成代码
+ * ⇒ 「写一句解释为什么删掉那条拒绝」这种正当改动变红，而红字指向的代码没坏。注释不是代码，
+ * 所以先剥再匹配。
+ *
+ * 两处细节是被测出来的，不是挑好看的：
+ * - **先剥块注释**：块注释里的 `//` 不是行注释的开头。
+ * - **行注释的 `//` 不能紧跟在 `:` 后面**：`"http://…"` 里的 `//` 是字符串的一部分，从这里
+ *   一直剥到行尾会把**同一行后面的代码**一起吃掉 —— 那会让真读字段的代码读成没读。假绿比
+ *   假红贵，所以这一步有自己的判别臂（见文件末尾那条测）。
+ */
+function stripComments(src) {
+  const withoutBlocks = src.replace(/\/\*[\s\S]*?\*\//g, "");
+  return withoutBlocks.replace(/(^|[^:])\/\/[^\n]*/g, "$1");
+}
+
+/**
+ * 这个字段名本身，按**整词**匹配。
+ *
+ * 子串匹配分不清 `ownStream` 与以它开头的更长的名字：`ownStreamRequestId` 是一次请求的 id，
+ * 读它与读流标记是两件事（issue #2771）。整词匹配把这两件事分开，而一条真拒绝不可能存在
+ * 却不出现这个名字的整词 —— 匹配变窄的代价因此为零。
+ */
+const OWN_STREAM_FIELD = /\bownStream\b/;
+
+/**
+ * 一条源码是否**在代码里**读了那个字段：先剥注释，再按整词匹配。
+ *
+ * 谓词有名字是有理由的：数测试的仪器按行首形状认「这一行是不是在定义一条测试」，
+ * `OWN_STREAM_FIELD.test(...)` 单独起一行会被它读成一条定义（issue #2771 实测）。
+ * 一个名字把「读一个字段」写成一句话，顺带让它不再长得像一条测试。
+ */
+const readsOwnStream = (text) => OWN_STREAM_FIELD.test(stripComments(text));
+
 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"),
+    !readsOwnStream(region),
     "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",
   );
@@ -79,3 +116,72 @@ test("区域取法本身会切分（换一个处理块取到的是另一块）",
   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");
 });
+
+// ── issue #2771：上面那条断言问的对象是「代码」，所以它得在注释与更长的名字上都读对 ──
+
+test("只点名 ownStream 的注释读作「没有代码读它」，真读它的一行仍然红", () => {
+  // 两向各一句，都在**字符串**上，不动 main.js：改真文件只能证明这一次，改不得下一次。
+  const commented = [
+    "async (_e, { sessionId } = {}) => {",
+    "  // the refusal removed in issue #2637 read connManager.get(prevSid).ownStream before",
+    "  // opening any connection: these lines name that field and read nothing from it.",
+    "  const prevSid = currentSessionId;",
+    "  return {};",
+    "}",
+  ].join("\n");
+  assert.ok(
+    !readsOwnStream(commented),
+    "a comment explaining why the refusal was removed must not be read as the refusal itself",
+  );
+
+  const refused = [
+    "async (_e, { sessionId } = {}) => {",
+    "  if (connManager.get(currentSessionId).ownStream) {",
+    '    throw new Error("session busy");',
+    "  }",
+    "}",
+  ].join("\n");
+  assert.ok(
+    readsOwnStream(refused),
+    "a handler that really refuses on the field must still be caught — this is the arm the guard exists for",
+  );
+
+  // 块注释同样是注释：`/* … */` 里的点名不算读。
+  const blockCommented = "  /* this used to read conn.ownStream — issue #2637 */\n  return {};";
+  assert.ok(!readsOwnStream(blockCommented), "a block comment is not code either");
+});
+
+test("以 ownStream 开头的更长的名字不是读这个字段", () => {
+  // `ownStreamRequestId` 是一次请求的 id，`_releaseOwnStream()` 是释放锁；两者都与「本处理块
+  // 是否因流标记拒绝」无关，而子串匹配会把前者读成后者（issue #2771 实测 `includes` 为 true）。
+  const longer = [
+    "  conn._releaseOwnStream();",
+    "  this.ownStreamRequestId = rid;",
+    "  if (frame.request_id === this.ownStreamRequestId) this._releaseOwnStream();",
+  ].join("\n");
+  assert.ok(
+    !readsOwnStream(longer),
+    "names that merely begin with the field are a different subject, and the guard must not redden them",
+  );
+  // 对照：这一类名字确实存在于本程序里，所以上一条不是在与一个假想的形状搏斗。
+  assert.ok(
+    source.includes("_releaseOwnStream"),
+    "control: the release helper this test excludes does exist in main.js",
+  );
+});
+
+test("字符串里的 // 不是注释起点（剥除不能吃掉同一行后面的代码）", () => {
+  // 这一条是剥除本身的判别臂，方向是**假绿**：若行注释的 `//` 不排除前面是 `:` 的那种，
+  // 一次 URL 字面量之后的所有代码都会被剥掉，于是同行的真拒绝读成「没读」。
+  const withUrl = '  const u = "http://example.test/x"; if (conn.ownStream) throw new Error("busy");';
+  assert.ok(
+    readsOwnStream(withUrl),
+    "a `//` inside a string literal must not swallow the code that follows it on the same line",
+  );
+  // 对照：同一行里真的是注释时，行尾的 `//` 之后不再算代码。
+  const withComment = '  const u = "http://example.test/x"; return {}; // ownStream lives elsewhere';
+  assert.ok(
+    !readsOwnStream(withComment),
+    "a trailing line comment is still a comment",
+  );
+});