Snippet naming: content-derived on publish, frozen on explicit rename

src/app/components/SnippetLibrary.test.tsx

@@ -89,6 +89,66 @@ describe('SnippetLibrary metadata panel (spec §02)', () => {
     expect(useSnippetStore.getState().snippets[0].name).toBe('Renamed');
   });
 
+  test('a publish-derived rename is adopted by the panel, not reverted by its auto-save', () => {
+    // Regression: the panel's local name state lagged a publish rename, so its
+    // debounced auto-save wrote the stale default back — the rename flickered
+    // for ~400ms in the list and then undid itself.
+    vi.useFakeTimers();
+    const s = createSnippet({ id: 'a', now: new Date('2026-01-01T00:00:00Z') }); // auto name
+    useSnippetStore.getState().hydrate([s], 'a');
+
+    act(() => {
+      root.render(<SnippetLibrary />);
+    });
+
+    act(() => {
+      useSnippetStore
+        .getState()
+        .updateDraft(
+          JSON.stringify({
+            mark: 'bar',
+            encoding: { x: { field: 'Region' }, y: { aggregate: 'count' } },
+          }),
+        );
+      useSnippetStore.getState().publish(new Date('2026-02-01T00:00:00Z'));
+    });
+
+    expect(nameInput().value).toBe('Bar chart of count by Region');
+    act(() => {
+      vi.advanceTimersByTime(1000); // any pending auto-save settles
+    });
+    expect(useSnippetStore.getState().snippets[0].name).toBe('Bar chart of count by Region');
+  });
+
+  test('a name edit in progress survives a publish rename (user text wins)', () => {
+    vi.useFakeTimers();
+    const s = createSnippet({ id: 'a', now: new Date('2026-01-01T00:00:00Z') });
+    useSnippetStore.getState().hydrate([s], 'a');
+
+    act(() => {
+      root.render(<SnippetLibrary />);
+    });
+
+    act(() => typeInto(nameInput(), 'My Chart')); // diverged, debounce pending
+    act(() => {
+      useSnippetStore
+        .getState()
+        .updateDraft(
+          JSON.stringify({
+            mark: 'bar',
+            encoding: { x: { field: 'Region' }, y: { aggregate: 'count' } },
+          }),
+        );
+      useSnippetStore.getState().publish();
+    });
+
+    expect(nameInput().value).toBe('My Chart'); // not clobbered by the derived name
+    act(() => {
+      vi.advanceTimersByTime(1000);
+    });
+    expect(useSnippetStore.getState().snippets[0].name).toBe('My Chart');
+  });
+
   test('does not loop on a search/sort state change (render-loop guard)', async () => {
     // A selector that returned a fresh filtered array would re-render forever
     // (MEMORY → "Zustand stable selectors"); the component derives via useMemo.

src/app/components/SnippetLibrary.tsx

@@ -99,6 +99,19 @@ function SnippetMeta({
   const [name, setName] = useState(snippet.name);
   const [comment, setCommentLocal] = useState(snippet.comment);
 
+  // The store can rename underneath this panel (publish's content-derived
+  // naming, spec §03D). Adopt the new store name unless the local field has
+  // diverged — i.e. the user is mid-edit, and their text wins. Without this,
+  // the stale local value differs from the store and the auto-save below
+  // writes the old name right back, silently undoing the publish rename.
+  const lastStoreName = useRef(snippet.name);
+  useEffect(() => {
+    if (snippet.name === lastStoreName.current) return;
+    const previous = lastStoreName.current;
+    lastStoreName.current = snippet.name;
+    setName((local) => (local === previous ? snippet.name : local));
+  }, [snippet.name]);
+
   useEffect(() => {
     if (name === snippet.name) return;
     const t = setTimeout(() => renameSnippet(snippet.id, name), META_AUTOSAVE_MS);