From cd4188fd5c28520d39708cbdaf492e4f213aea60 Mon Sep 17 00:00:00 2001
From: Andrew Cherniavskyi <andrew@mui.com>
Date: Mon, 2 Dec 2024 13:40:35 +0100
Subject: [PATCH] fix tests

---
 .../features/rowPinning/useGridRowPinningPreProcessors.ts      | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/x-data-grid-pro/src/hooks/features/rowPinning/useGridRowPinningPreProcessors.ts b/packages/x-data-grid-pro/src/hooks/features/rowPinning/useGridRowPinningPreProcessors.ts
index c058cc45115c..586e4f2f4f4a 100644
--- a/packages/x-data-grid-pro/src/hooks/features/rowPinning/useGridRowPinningPreProcessors.ts
+++ b/packages/x-data-grid-pro/src/hooks/features/rowPinning/useGridRowPinningPreProcessors.ts
@@ -111,7 +111,8 @@ export const useGridRowPinningPreProcessors = (
 
       if (prevPinnedRowsCache) {
         const pinnedRowCleanup = (rowId: GridRowId) => {
-          if (newGroupingParams.tree[rowId].type === 'pinnedRow') {
+          const node = newGroupingParams.tree[rowId];
+          if (node?.type === 'pinnedRow') {
             delete newGroupingParams.tree[rowId];
             delete newGroupingParams.dataRowIdToModelLookup[rowId];
             delete newGroupingParams.dataRowIdToIdLookup[rowId];