fix(editor): wait for pending completions on Tab

apps/desktop/src/components/editor/QueryEditor.vue

@@ -119,6 +119,9 @@ const props = defineProps<{
 }>();
 
 const COMPLETION_REMOTE_LATENCY_BUDGET_MS = 120;
+const COMPLETION_DEBOUNCE_DELAY_MS = 150;
+const COMPLETION_TAB_RETRY_DELAY_MS = 16;
+const COMPLETION_TAB_MAX_WAIT_MS = COMPLETION_DEBOUNCE_DELAY_MS + COMPLETION_REMOTE_LATENCY_BUDGET_MS + 100;
 // Internal rollback switch: flip to false to route completion, diagnostics, and navigation through the legacy SQL context path.
 const SEMANTIC_SQL_COMPLETION_ENABLED = true;
 
@@ -338,6 +341,7 @@ let codeMirrorRedo: typeof import("@codemirror/commands").redo | null = null;
 let codeMirrorSelectAll: typeof import("@codemirror/commands").selectAll | null = null;
 let codeMirrorInsertNewlineKeepIndent: typeof import("@codemirror/commands").insertNewlineKeepIndent | null = null;
 let codeMirrorToggleLineComment: typeof import("@codemirror/commands").toggleLineComment | null = null;
+let pendingCompletionTabTimer: ReturnType<typeof setTimeout> | null = null;
 let setSqlDiagnosticsEffect: import("@codemirror/state").StateEffectType<SqlSemanticDiagnostic[]> | null = null;
 let setPreviewRangeEffect:
   | import("@codemirror/state").StateEffectType<{
@@ -527,7 +531,11 @@ function editorIndentUnit(): string {
 }
 
 function handleTab(view: EditorViewType): boolean {
-  if (codeMirrorCompletionStatus?.(view.state) === "active") return false;
+  if (codeMirrorCompletionStatus?.(view.state)) return false;
+  return performNormalTab(view);
+}
+
+function performNormalTab(view: EditorViewType): boolean {
   const { state, dispatch } = view;
   const sel = state.selection.main;
   if (!sel.empty) return codeMirrorIndentMore?.(view) ?? false;
@@ -1337,12 +1345,48 @@ function runKeymapExtension(codeMirrorKeymap: (typeof import("@codemirror/view")
 }
 
 function acceptCompletionOrNextSnippetField(view: EditorViewType): boolean {
-  if (codeMirrorCompletionStatus?.(view.state) && (codeMirrorAcceptCompletion?.(view) ?? false)) {
-    return true;
-  }
-  // Table/column completions can happen inside a CodeMirror snippet field. When
-  // the completion popup is gone, Tab should continue through the snippet fields.
-  return codeMirrorNextSnippetField?.(view) ?? false;
+  const completionStatus = codeMirrorCompletionStatus?.(view.state) ?? null;
+  if (completionStatus === "active" && (codeMirrorAcceptCompletion?.(view) ?? false)) return true;
+  // Snippet fields keep their normal immediate Tab priority when completion
+  // is pending or still inside CodeMirror's interaction delay.
+  if (codeMirrorNextSnippetField?.(view)) return true;
+  if (completionStatus) return waitForCompletionTab(view);
+  return false;
+}
+
+function clearPendingCompletionTab() {
+  if (pendingCompletionTabTimer === null) return;
+  clearTimeout(pendingCompletionTabTimer);
+  pendingCompletionTabTimer = null;
+}
+
+function waitForCompletionTab(view: EditorViewType): boolean {
+  clearPendingCompletionTab();
+  const initialDoc = view.state.doc;
+  const initialSelection = view.state.selection.main;
+  const startedAt = Date.now();
+
+  const retry = () => {
+    pendingCompletionTabTimer = null;
+    const selection = view.state.selection.main;
+    if (view.state.doc !== initialDoc || selection.anchor !== initialSelection.anchor || selection.head !== initialSelection.head) return;
+
+    const completionStatus = codeMirrorCompletionStatus?.(view.state) ?? null;
+    if (completionStatus === "active" && (codeMirrorAcceptCompletion?.(view) ?? false)) return;
+    if (codeMirrorNextSnippetField?.(view)) return;
+    if (completionStatus && Date.now() - startedAt < COMPLETION_TAB_MAX_WAIT_MS) {
+      pendingCompletionTabTimer = setTimeout(retry, COMPLETION_TAB_RETRY_DELAY_MS);
+      return;
+    }
+
+    // A pending completion may resolve without any applicable option. Preserve
+    // snippet navigation first, then fall back to the editor's normal Tab action.
+    if (codeMirrorNextSnippetField?.(view)) return;
+    performNormalTab(view);
+  };
+
+  pendingCompletionTabTimer = setTimeout(retry, COMPLETION_TAB_RETRY_DELAY_MS);
+  return true;
 }
 
 function wordWrapExtension() {
@@ -2513,7 +2557,7 @@ async function provideSqlCompletions(context: CompletionContext) {
         } catch {
           resolve(localResult);
         }
-      }, 150);
+      }, COMPLETION_DEBOUNCE_DELAY_MS);
     });
   } catch {
     return null;
@@ -4108,6 +4152,7 @@ function pauseQueryEditorBackgroundWork() {
   flushEditorViewport();
   flushEditorSelection();
   clearTableNavigationHover();
+  clearPendingCompletionTab();
   editorIsActive = false;
   clearScheduledSemanticDiagnostics();
   completionEpoch++;