fix: optimize getAriaRowIndexMap performance (#98)

Author: astandrik

.github/workflows/pr-preview-build.yml

@@ -8,6 +8,6 @@ jobs:
     name: Build
     runs-on: ubuntu-latest
     steps:
-      - uses: gravity-ui/preview-build-action@v1
+      - uses: gravity-ui/preview-build-action@v2
         with:
           node-version: 20

src/utils/getAriaRowIndexMap.ts

@@ -1,20 +1,20 @@
 import type {Row} from '@tanstack/react-table';
 
 export const getAriaRowIndexMap = <TData>(rows: Row<TData>[]) => {
+    const map: Record<string, number> = {};
     let rowIndex = 1;
 
-    return rows.reduce<Record<string, number>>((acc, row, index, arr) => {
-        const newMap = {
-            ...acc,
-            [row.id]: rowIndex,
-        };
+    for (let i = 0; i < rows.length; i++) {
+        const row = rows[i];
+        const nextRow = rows[i + 1];
+
+        map[row.id] = rowIndex;
 
-        const nextRow = arr[index + 1];
         if (nextRow?.parentId !== row.id) {
             rowIndex += row.getLeafRows().length;
         }
         rowIndex++;
+    }
 
-        return newMap;
-    }, {});
+    return map;
 };