Prevent unintentional trashing of non-empty untitled drafts on editor unmount (#12418)

* Initial plan

* Fix draft auto-delete check for non-empty untitled docs

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

app/scenes/Document/hooks/useDocumentSave.test.ts

@@ -0,0 +1,31 @@
+import { shouldAutoDeleteDraftOnUnmount } from "./useDocumentSave";
+
+describe("shouldAutoDeleteDraftOnUnmount", () => {
+  const baseOptions = {
+    title: "",
+    createdById: "user-1",
+    currentUserId: "user-1",
+    isDraft: true,
+    isActive: true,
+    hasEmptyTitle: true,
+    isPersistedOnce: true,
+  };
+
+  it("does not auto delete drafts with non-empty editor content", () => {
+    expect(
+      shouldAutoDeleteDraftOnUnmount({
+        ...baseOptions,
+        isEditorEmpty: false,
+      })
+    ).toBe(false);
+  });
+
+  it("auto deletes drafts that are still empty and untitled", () => {
+    expect(
+      shouldAutoDeleteDraftOnUnmount({
+        ...baseOptions,
+        isEditorEmpty: true,
+      })
+    ).toBe(true);
+  });
+});

app/scenes/Document/hooks/useDocumentSave.ts

@@ -50,6 +50,36 @@ interface UseDocumentSaveResult {
   onFileUploadStop: () => void;
 }
 
+export function shouldAutoDeleteDraftOnUnmount({
+  isEditorEmpty,
+  title,
+  createdById,
+  currentUserId,
+  isDraft,
+  isActive,
+  hasEmptyTitle,
+  isPersistedOnce,
+}: {
+  isEditorEmpty: boolean;
+  title: string;
+  createdById?: string;
+  currentUserId?: string;
+  isDraft: boolean;
+  isActive: boolean;
+  hasEmptyTitle: boolean;
+  isPersistedOnce: boolean;
+}) {
+  return (
+    isEditorEmpty &&
+    title.trim() === "" &&
+    createdById === currentUserId &&
+    isDraft &&
+    isActive &&
+    hasEmptyTitle &&
+    isPersistedOnce
+  );
+}
+
 /**
  * Hook that encapsulates save, autosave, dirty-tracking, and template
  * insertion logic for the document editor scene.
@@ -77,8 +107,6 @@ export function useDocumentSave({
   // Companion refs for stale closure avoidance
   const isEditorDirtyRef = useRef(isEditorDirty);
   isEditorDirtyRef.current = isEditorDirty;
-  const isEmptyRef = useRef(isEmpty);
-  isEmptyRef.current = isEmpty;
   const titleRef = useRef(title);
   titleRef.current = title;
 
@@ -89,7 +117,6 @@ export function useDocumentSave({
     isEditorDirtyRef.current = dirty;
     const empty = (!doc || ProsemirrorHelper.isEmpty(doc)) && !titleRef.current;
     setIsEmpty(empty);
-    isEmptyRef.current = empty;
   }, [document, editorRef]);
 
   const updateIsDirtyRef = useRef(updateIsDirty);
@@ -313,14 +340,20 @@ export function useDocumentSave({
   useEffect(
     () => () => {
       autosave.cancel();
+      const currentDoc = editorRef.current?.view.state.doc;
+      const isEditorEmpty = !currentDoc || ProsemirrorHelper.isEmpty(currentDoc);
 
       if (
-        isEmptyRef.current &&
-        document.createdBy?.id === auth.user?.id &&
-        document.isDraft &&
-        document.isActive &&
-        document.hasEmptyTitle &&
-        document.isPersistedOnce
+        shouldAutoDeleteDraftOnUnmount({
+          isEditorEmpty,
+          title: titleRef.current,
+          createdById: document.createdBy?.id,
+          currentUserId: auth.user?.id,
+          isDraft: document.isDraft,
+          isActive: document.isActive,
+          hasEmptyTitle: document.hasEmptyTitle,
+          isPersistedOnce: document.isPersistedOnce,
+        })
       ) {
         void document.delete();
       } else if (document.isDirty()) {