fix: improve auto save stability

src/extension/panelSession.ts

@@ -328,25 +328,56 @@ export function createPanelSessionController(params: PanelSessionControllerParam
     return applyQueue;
   };
 
-  const applyPendingDraftIfNeeded = async (): Promise<void> => {
+  const reportBackgroundError = (contextLabel: string, error: unknown): void => {
+    if (disposed) {
+      return;
+    }
+    console.error(`[MEO panelSession] ${contextLabel}`, error);
+  };
+
+  const runBackground = (promise: Promise<unknown>, contextLabel: string): void => {
+    void promise.catch((error) => {
+      reportBackgroundError(contextLabel, error);
+    });
+  };
+
+  const postToWebview = async (message: Record<string, unknown>): Promise<boolean> => {
+    if (disposed) {
+      return false;
+    }
+    try {
+      return await panel.webview.postMessage(message);
+    } catch {
+      return false;
+    }
+  };
+
+  const saveDocumentIfAutoSaveEnabled = async (): Promise<void> => {
+    if (!getAutoSaveEnabled(context) || !document.isDirty) {
+      return;
+    }
+    await document.save();
+  };
+
+  const applyPendingDraftIfNeeded = async (): Promise<boolean> => {
     const draftText = pendingDraftText;
     pendingDraftText = null;
     if (draftText === null) {
-      return;
+      return false;
     }
 
     const currentText = document.getText();
     const normalizedCurrent = currentText.replace(/\r\n/g, '\n');
     const normalizedDraft = draftText.replace(/\r\n/g, '\n');
     if (normalizedCurrent === normalizedDraft) {
-      return;
+      return false;
     }
 
     const edit = new vscode.WorkspaceEdit();
     const fullRange = new vscode.Range(document.positionAt(0), document.positionAt(currentText.length));
     agentReviewHandoff.noteRecentMEOOwnedFileChangeForUri(document.uri);
     edit.replace(document.uri, fullRange, draftText);
-    await vscode.workspace.applyEdit(edit);
+    return vscode.workspace.applyEdit(edit);
   };
 
   const sendInit = async (): Promise<boolean> => {
@@ -365,7 +396,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
       outlineVisible: getOutlineVisible(context),
       theme: getThemeSettings()
     };
-    return panel.webview.postMessage(message);
+    return postToWebview(message);
   };
 
   const sendDocChanged = async (): Promise<boolean> => {
@@ -374,7 +405,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
       text: document.getText(),
       version: document.version
     };
-    return panel.webview.postMessage(message);
+    return postToWebview(message);
   };
 
   const sendApplied = async (version: number): Promise<boolean> => {
@@ -382,7 +413,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
       type: 'applied',
       version
     };
-    return panel.webview.postMessage(message);
+    return postToWebview(message);
   };
 
   const sendGitBaselineChanged = async (options: RefreshGitBaselineOptions = {}): Promise<boolean> => {
@@ -405,7 +436,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
       version: document.version,
       payload
     };
-    const posted = await panel.webview.postMessage(message);
+    const posted = await postToWebview(message);
     if (posted) {
       gitDocumentState.setLastSentBaselineHash(payloadHash);
     }
@@ -437,7 +468,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
   };
 
   const ensureInitDelivered = async (): Promise<void> => {
-    if (initDelivered) {
+    if (disposed || initDelivered) {
       return;
     }
     const posted = await sendInit();
@@ -448,6 +479,9 @@ export function createPanelSessionController(params: PanelSessionControllerParam
 
   const requestExportSnapshot = async (): Promise<{ text: string; environment?: ExportStyleEnvironment }> => {
     await ensureInitDelivered();
+    if (disposed) {
+      throw new Error('The editor was closed before export completed.');
+    }
     const requestId = `export-${Date.now()}-${Math.random().toString(36).slice(2, 10)}`;
 
     const response = new Promise<{ text: string; environment?: ExportStyleEnvironment }>((resolve, reject) => {
@@ -463,7 +497,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
       type: 'requestExportSnapshot',
       requestId
     };
-    const posted = await panel.webview.postMessage(message);
+    const posted = await postToWebview(message);
     if (!posted) {
       rejectPendingExportSnapshot(requestId, new Error('The editor webview is not ready to export.'));
     }
@@ -524,7 +558,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
     } finally {
       gitRefreshRunning = false;
       if (gitRefreshPending) {
-        void runPendingGitRefreshes();
+        runBackground(runPendingGitRefreshes(), 'runPendingGitRefreshes.retry');
       }
     }
   };
@@ -536,7 +570,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
     gitRefreshPending = true;
     gitRefreshPendingForcePost = gitRefreshPendingForcePost || options.forcePost === true;
     gitRefreshPendingForceReload = gitRefreshPendingForceReload || options.forceReload === true;
-    void runPendingGitRefreshes();
+    runBackground(runPendingGitRefreshes(), 'runPendingGitRefreshes');
   };
 
   const isTextEditorForDocument = (textEditor: vscode.TextEditor | undefined): textEditor is vscode.TextEditor => {
@@ -563,7 +597,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
       anchor: selection.anchor,
       head: selection.head
     };
-    const posted = await panel.webview.postMessage(message);
+    const posted = await postToWebview(message);
     if (posted) {
       lastSentRevealSelectionKey = getRevealSelectionKey(selection);
       pendingRevealSelection = null;
@@ -582,7 +616,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
   const postFocusEditor = async (): Promise<void> => {
     await ensureInitDelivered();
     const message: FocusEditorMessage = { type: 'focusEditor' };
-    await panel.webview.postMessage(message);
+    await postToWebview(message);
   };
 
   const sendRevealSelectionForEditor = async (textEditor: vscode.TextEditor | undefined): Promise<void> => {
@@ -627,6 +661,9 @@ export function createPanelSessionController(params: PanelSessionControllerParam
   };
 
   const handleMessage = async (raw: WebviewMessage): Promise<void> => {
+    if (disposed) {
+      return;
+    }
     switch (raw.type) {
       case 'ready':
         await ensureInitDelivered();
@@ -685,7 +722,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
           requestId: raw.requestId,
           resolvedUrl: resolveWebviewImageSrc(raw.url, documentUri, panel.webview)
         };
-        await panel.webview.postMessage(response);
+        await postToWebview(response);
         return;
       }
       case 'resolveWikiLinks': {
@@ -694,7 +731,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
           requestId: raw.requestId,
           results: await resolveWikiLinkTargets(raw.targets, documentUri)
         };
-        await panel.webview.postMessage(response);
+        await postToWebview(response);
         return;
       }
       case 'exportSnapshot':
@@ -715,7 +752,7 @@ export function createPanelSessionController(params: PanelSessionControllerParam
           localEditGeneration: raw.localEditGeneration,
           result: resolved.result
         };
-        await panel.webview.postMessage(response);
+        await postToWebview(response);
         return;
       }
       case 'openGitRevisionForLine':
@@ -728,7 +765,10 @@ export function createPanelSessionController(params: PanelSessionControllerParam
         agentReviewHandoff.noteRecentMEOOwnedFileChangeForUri(document.uri);
         isApplyingOwnChange = true;
         try {
-          await enqueue(() => applyDocumentChanges(document, raw, sendDocChanged, sendApplied));
+          await enqueue(async () => {
+            await applyDocumentChanges(document, raw, sendDocChanged, sendApplied);
+            await saveDocumentIfAutoSaveEnabled();
+          });
         } finally {
           isApplyingOwnChange = false;
         }
@@ -748,14 +788,14 @@ export function createPanelSessionController(params: PanelSessionControllerParam
         return;
       case 'saveImageFromClipboard': {
         const response = await handleSaveImageFromClipboard(raw, documentUri);
-        await panel.webview.postMessage(response);
+        await postToWebview(response);
         return;
       }
     }
   };
 
   const messageSubscription = panel.webview.onDidReceiveMessage((raw: WebviewMessage) => {
-    void handleMessage(raw);
+    runBackground(handleMessage(raw), 'handleMessage');
   });
 
   const documentChangeSubscription = vscode.workspace.onDidChangeTextDocument((event) => {
@@ -772,9 +812,9 @@ export function createPanelSessionController(params: PanelSessionControllerParam
       return;
     }
 
-    void enqueue(async () => {
+    runBackground(enqueue(async () => {
       await sendDocChanged();
-    });
+    }), 'sendDocChanged');
   });
 
   const documentSaveSubscription = vscode.workspace.onDidSaveTextDocument((savedDocument) => {
@@ -788,27 +828,27 @@ export function createPanelSessionController(params: PanelSessionControllerParam
     if (!isTextEditorForDocument(event.textEditor)) {
       return;
     }
-    void sendRevealSelectionForEditor(event.textEditor);
+    runBackground(sendRevealSelectionForEditor(event.textEditor), 'sendRevealSelectionForEditor.selection');
   });
 
   const activeTextEditorSubscription = vscode.window.onDidChangeActiveTextEditor((textEditor) => {
     if (!isTextEditorForDocument(textEditor)) {
       return;
     }
-    void sendRevealSelectionForEditor(textEditor);
+    runBackground(sendRevealSelectionForEditor(textEditor), 'sendRevealSelectionForEditor.activeEditor');
   });
 
   const visibleTextEditorsSubscription = vscode.window.onDidChangeVisibleTextEditors(() => {
-    void sendRevealSelectionForEditor(findEditorForDocumentReveal());
+    runBackground(sendRevealSelectionForEditor(findEditorForDocumentReveal()), 'sendRevealSelectionForEditor.visibleEditors');
   });
 
   const viewStateSubscription = panel.onDidChangeViewState((event) => {
     if (event.webviewPanel.active) {
       onPanelActivated(event.webviewPanel);
       refreshGitBaseline({ forcePost: true });
-      void flushPendingRevealSelection();
-      void sendRevealSelectionForEditor(findEditorForDocumentReveal());
-      void postFocusEditor();
+      runBackground(flushPendingRevealSelection(), 'flushPendingRevealSelection');
+      runBackground(sendRevealSelectionForEditor(findEditorForDocumentReveal()), 'sendRevealSelectionForEditor.viewState');
+      runBackground(postFocusEditor(), 'postFocusEditor');
     }
     onPanelViewStateChanged();
   });
@@ -817,9 +857,9 @@ export function createPanelSessionController(params: PanelSessionControllerParam
     dispose();
   });
 
-  void ensureInitDelivered();
+  runBackground(ensureInitDelivered(), 'ensureInitDelivered.startup');
   refreshGitBaseline({ forcePost: true });
-  void sendRevealSelectionForEditor(findEditorForDocumentReveal());
+  runBackground(sendRevealSelectionForEditor(findEditorForDocumentReveal()), 'sendRevealSelectionForEditor.startup');
 
   const dispose = (): void => {
     if (disposed) {
@@ -827,14 +867,17 @@ export function createPanelSessionController(params: PanelSessionControllerParam
     }
     disposed = true;
 
-    void enqueue(async () => {
+    runBackground(enqueue(async () => {
       try {
         // Best-effort recovery for edits that never made it through the debounce/apply round-trip.
-        await applyPendingDraftIfNeeded();
+        const recovered = await applyPendingDraftIfNeeded();
+        if (recovered) {
+          await saveDocumentIfAutoSaveEnabled();
+        }
       } catch {
         // Ignore dispose-time recovery failures to avoid surfacing noisy teardown errors.
       }
-    });
+    }), 'disposeDraftRecovery');
 
     rejectPendingExportSnapshots(new Error('The editor was closed before export completed.'));
     messageSubscription.dispose();

webview/src/index.ts

@@ -417,7 +417,13 @@ const findPanelController = createFindPanelController(findPanelElements, () => e
 const selectionMenuElements = createSelectionMenu();
 const selectionMenuController = createSelectionMenuController(selectionMenuElements, () => editor);
 
-toolbar.replaceChildren(formatGroup, rightGroup, modeGroup, findPanelElements.panel);
+const editorNoticeBanner = document.createElement('div');
+editorNoticeBanner.className = 'editor-notice';
+editorNoticeBanner.setAttribute('role', 'status');
+editorNoticeBanner.setAttribute('aria-live', 'polite');
+editorNoticeBanner.hidden = true;
+
+toolbar.replaceChildren(formatGroup, rightGroup, modeGroup, findPanelElements.panel, editorNoticeBanner);
 
 const existingEditorWrapper = root.querySelector('.editor-wrapper');
 const editorWrapper = existingEditorWrapper instanceof HTMLElement ? existingEditorWrapper : document.createElement('div');
@@ -461,9 +467,28 @@ let hasSentDraftText = false;
 let initialEditorMountInFlight = false;
 let createEditorFactoryPromise: Promise<CreateEditorFactory> | null = null;
 
+const setEditorNotice = (message: string, kind = 'info') => {
+  const normalizedMessage = `${message ?? ''}`.trim();
+  if (!normalizedMessage) {
+    clearEditorNotice();
+    return;
+  }
+  editorNoticeBanner.textContent = normalizedMessage;
+  editorNoticeBanner.dataset.kind = kind;
+  editorNoticeBanner.hidden = false;
+  editorNoticeBanner.classList.add('is-visible');
+};
+
+const clearEditorNotice = () => {
+  editorNoticeBanner.textContent = '';
+  delete editorNoticeBanner.dataset.kind;
+  editorNoticeBanner.hidden = true;
+  editorNoticeBanner.classList.remove('is-visible');
+};
+
 const editorNotice: EditorNotice = {
-  setEditorNotice: (_message, _kind = 'info') => {},
-  clearEditorNotice: () => {}
+  setEditorNotice,
+  clearEditorNotice
 };
 
 const failureNotice = createFailureNoticeManager(editorNotice);
@@ -1127,9 +1152,6 @@ window.addEventListener('message', (event) => {
     flushChanges();
     maybeSaveAfterSync();
     syncPendingDraftState();
-    if (autoSaveEnabled && !inFlight && pendingText !== null && normalizeEol(pendingText) === syncedText) {
-      vscode.postMessage({ type: 'saveDocument' });
-    }
     return;
   }
 
@@ -1245,25 +1267,7 @@ window.addEventListener('visibilitychange', () => {
 });
 
 const forceFlushChanges = () => {
-  if (!editor || pendingText === null) {
-    return;
-  }
-
-  const nextText = pendingText;
-  const message: WebviewMessage = {
-    type: 'applyChanges',
-    baseVersion: documentVersion,
-    changes: [
-      {
-        from: 0,
-        to: syncedText.length,
-        insert: nextText
-      }
-    ]
-  };
-
-  documentVersion++;
-  vscode.postMessage(message);
+  flushChanges();
 };
 
 window.addEventListener('beforeunload', () => {

webview/src/styles.css

@@ -107,6 +107,42 @@ body {
   background-color: var(--vscode-sideBar-background);
 }
 
+.editor-notice {
+  display: none;
+  position: absolute;
+  top: calc(100% + 4px);
+  left: 14px;
+  right: 14px;
+  padding: 6px 10px;
+  border: 1px solid var(--vscode-inputValidation-infoBorder, var(--vscode-panel-border));
+  border-radius: 6px;
+  color: var(--vscode-inputValidation-infoForeground, var(--vscode-editor-foreground));
+  background: var(
+    --vscode-inputValidation-infoBackground,
+    var(--vscode-editorWidget-background, var(--vscode-sideBar-background))
+  );
+  font-size: 12px;
+  line-height: 1.4;
+  z-index: 275;
+  pointer-events: none;
+}
+
+.editor-notice.is-visible {
+  display: block;
+}
+
+.editor-notice[data-kind='warning'] {
+  border-color: var(--vscode-inputValidation-warningBorder, #b89500);
+  color: var(--vscode-inputValidation-warningForeground, var(--vscode-editor-foreground));
+  background: var(--vscode-inputValidation-warningBackground, rgba(184, 149, 0, 0.18));
+}
+
+.editor-notice[data-kind='error'] {
+  border-color: var(--vscode-inputValidation-errorBorder, #be1100);
+  color: var(--vscode-inputValidation-errorForeground, #ffffff);
+  background: var(--vscode-inputValidation-errorBackground, rgba(190, 17, 0, 0.3));
+}
+
 .find-panel {
   display: none;
   position: absolute;