fix(editor): clear stale text focus when switching tabs

src/editor/core/controller.test.ts

@@ -1,4 +1,4 @@
-import { afterEach, describe, expect, it } from "vitest";
+import { afterEach, describe, expect, it, vi } from "vitest";
 import { EditorController, openFilePaths, useEditorStatus, useTabs } from "./controller";
 import { createMemoryBackend } from "./backend";
 import { initialTabsState } from "./model/tabs";
@@ -7,6 +7,9 @@ import { resetDistractionFree, setDistractionFree } from "@/workbench/distractio
 import { registerActions } from "@/platform/actions";
 import { useProject } from "@/platform/project";
 import { resolveMenuItems } from "@/ui";
+import { getContext } from "@/platform/context";
+import { installKeyboardDispatcher } from "@/platform/keymap";
+import { TEXT_WHEN } from "./actions";
 
 let ctrl: EditorController | null = null;
 
@@ -18,6 +21,72 @@ afterEach(() => {
 });
 
 describe("EditorController", () => {
+  it("leaves modified Enter to a non-text editor after switching from a focused file", async () => {
+    ctrl = new EditorController(createMemoryBackend({ "/p/a.ts": "one\ntwo\n" }));
+    ctrl.start();
+    await ctrl.openFile("/p/a.ts", { focus: false });
+    const slot = ctrl.activeSlot!;
+    const host = document.createElement("div");
+    document.body.appendChild(host);
+    const view = slot.mount(host);
+    ctrl.onMounted(slot);
+    view.focus();
+    await vi.waitFor(() => expect(getContext().editorTextFocus).toBe(true));
+
+    const splitLine = vi.fn();
+    const dispose = registerActions([
+      {
+        id: "code.splitLine",
+        title: "Split Line",
+        when: TEXT_WHEN,
+        run: splitLine,
+      },
+    ]);
+    const uninstall = installKeyboardDispatcher(window);
+    const message = document.createElement("textarea");
+    const send = vi.fn();
+    message.addEventListener("keydown", send);
+    try {
+      await ctrl.openInput({ kind: "agent-session", key: "task" });
+      slot.unmount();
+      host.appendChild(message);
+      message.focus();
+      message.dispatchEvent(
+        new KeyboardEvent("keydown", {
+          key: "Enter",
+          code: "Enter",
+          metaKey: true,
+          bubbles: true,
+          cancelable: true,
+        }),
+      );
+      expect(splitLine).not.toHaveBeenCalled();
+      expect(send).toHaveBeenCalledOnce();
+      expect(getContext().editorTextFocus).toBe(false);
+
+      await ctrl.openFile("/p/a.ts", { focus: false });
+      const reopened = slot.mount(host);
+      ctrl.onMounted(slot);
+      reopened.focus();
+      await vi.waitFor(() => expect(getContext().editorTextFocus).toBe(true));
+      reopened.contentDOM.dispatchEvent(
+        new KeyboardEvent("keydown", {
+          key: "Enter",
+          code: "Enter",
+          metaKey: true,
+          bubbles: true,
+          cancelable: true,
+        }),
+      );
+      expect(splitLine).toHaveBeenCalledOnce();
+    } finally {
+      uninstall();
+      dispose();
+      slot.unmount();
+      host.remove();
+    }
+  });
+
   it("updates the caret status synchronously on programmatic selection changes", async () => {
     ctrl = new EditorController(createMemoryBackend({ "/p/a.ts": "one\ntwo\nthree\n" }));
     ctrl.start();

src/editor/core/controller.ts

@@ -713,6 +713,7 @@ export class EditorController implements SlotHost {
       Object.values(s.panes).some((p) => p.tabs.length > 0),
     );
     setContext("editorSplit", paneIds(s).length > 1);
+    setContext("editorTextFocus", !!slot?.view?.hasFocus);
     setContext("textEditorActive", !!slot);
   }