feat: support pivots menu (#1755)

packages/component/src/ui/tree-view/utils.ts

@@ -0,0 +1,18 @@
+import type { Node } from '@affine/component';
+
+export function flattenIds<RenderProps>(arr: Node<RenderProps>[]): string[] {
+  const result: string[] = [];
+
+  function flatten(arr: Node<RenderProps>[]) {
+    for (let i = 0, len = arr.length; i < len; i++) {
+      const item = arr[i];
+      result.push(item.id);
+      if (Array.isArray(item.children)) {
+        flatten(item.children);
+      }
+    }
+  }
+
+  flatten(arr);
+  return result;
+}