fix(editor): auto-save when the app is deactivated while focus is in a frame (#1636)

With focus in a plugin's web view, the window's blur fires when the frame takes focus, before any edit, and not again when the user switches applications, so edits made in the frame weren't auto-saved. The editor now also saves on the application-deactivated event.

src/editor/core/backend.ts

@@ -21,6 +21,7 @@ import {
   type SyntaxHighlights,
   type TextChange,
 } from "@/platform/ipc";
+import { getCurrentWebviewWindow } from "@tauri-apps/api/webviewWindow";
 
 import { EditorState } from "@codemirror/state";
 import { customRegions } from "./cm/regions";
@@ -60,6 +61,11 @@ export interface DocBackend {
   onDirty(handler: (e: { doc: DocId; dirty: boolean }) => void): () => void;
   /** Files changed on disk (used to refresh nothing but closed-file state). */
   onFsChanged?(handler: (e: { removed: string[] }) => void): () => void;
+  /**
+   * Every OpenIDEA window lost focus to another application. Also seen while focus is in a frame
+   * (a plugin's web view), which hides the window's own `blur`.
+   */
+  onApplicationDeactivated?(handler: () => void): () => void;
   /**
    * An open document's language changed (Settings › File Types, Override File
    * Type), or its own mode (`DocumentInfo.uiMode`).
@@ -86,6 +92,11 @@ export const ipcBackend: DocBackend = {
   onPatched: (h) => onIdeEvent("docPatched", (e) => h(e)),
   onDirty: (h) => onIdeEvent("docDirty", (e) => h(e)),
   onFsChanged: (h) => onIdeEvent("fsChanged", (e) => h(e)),
+  onApplicationDeactivated: (h) => {
+    if (!isTauri()) return () => {};
+    const listener = getCurrentWebviewWindow().listen("ide://application-deactivated", () => h());
+    return () => void listener.then((unlisten) => unlisten());
+  },
   onLanguage: (h) => onIdeEvent("docLanguage", (e) => h(e)),
 };
 

src/editor/core/controller.ts

@@ -353,6 +353,8 @@ export class EditorController implements SlotHost {
         void this.saveCustomDocuments(true).catch((e) => this.documentError(e));
       }
     };
+    if (this.manager.backend.onApplicationDeactivated)
+      this.disposers.push(this.manager.backend.onApplicationDeactivated(onWindowBlur));
     const onPageHide = () => this.saveSession();
     if (typeof window !== "undefined") {
       if (this.manager.backend.syncFromDisk)

src/editor/core/customDocuments.test.ts

@@ -481,6 +481,24 @@ describe("custom editor document lifetime", () => {
     expect(findTab(useTabs.getState(), input().key)).toBeNull();
   });
 
+  it("autosaves when the application is deactivated while focus is in a frame", async () => {
+    ctrl.stop();
+    let deactivated = () => {};
+    ctrl = new EditorController({
+      ...createMemoryBackend(),
+      onApplicationDeactivated: (handler) => {
+        deactivated = handler;
+        return () => {};
+      },
+    });
+    ctrl.start();
+    const doc = await open();
+    useProject.setState({ settings: { files: { autoSave: true } } as never });
+    // Focus inside a plugin's frame: the window's own blur has already fired, before the edit.
+    deactivated();
+    await vi.waitFor(() => expect(doc.saved).toBe("edited"));
+  });
+
   it("does not prompt or blur-autosave a document until execution has drained", async () => {
     const doc = await open();
     useProject.setState({ settings: { files: { autoSave: true } } as never });