fix(DataTable): guard npe when cells being sorted do not exist (#9714)

* fix(DataTable): guard npe when cells being sorted do not exist

* fix(DataTable): add unit tests

Co-authored-by: Holman Sze <hoiwingh@ca.ibm.com>
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

Author: 3 people

packages/react/src/components/DataTable/tools/__tests__/sorting-test.js

@@ -5,9 +5,56 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import { defaultSortRow } from '../sorting';
+import { sortRows, defaultSortRow } from '../sorting';
 import { sortStates } from '../../state/sorting';
 
+describe('sortRow', () => {
+  const rowIds = ['row2', 'row1'];
+  const cellsById = {
+    'row1:header1': { value: 'cell11' },
+    'row2:header1': { value: 'cell21' },
+  };
+
+  it('should sort data in ascending order', () => {
+    expect(
+      sortRows({
+        rowIds,
+        cellsById,
+        sortDirection: sortStates.ASC,
+        key: 'header1',
+        locale: 'en',
+        sortRow: defaultSortRow,
+      })
+    ).toEqual(['row1', 'row2']);
+  });
+
+  it('should sort data in descending order', () => {
+    expect(
+      sortRows({
+        rowIds,
+        cellsById,
+        sortDirection: sortStates.DESC,
+        key: 'header1',
+        locale: 'en',
+        sortRow: defaultSortRow,
+      })
+    ).toEqual(['row2', 'row1']);
+  });
+
+  it('should return unsorted data if cells not found', () => {
+    expect(
+      sortRows({
+        rowIds,
+        cellsById,
+        sortDirection: sortStates.ASC,
+        key: 'header2',
+        locale: 'en',
+        sortRow: defaultSortRow,
+      })
+    ).toEqual(['row2', 'row1']);
+  });
+});
+
 describe('defaultSortRow', () => {
   it('should sort data in ascending order', () => {
     const sortProps = {

packages/react/src/components/DataTable/tools/sorting.js

@@ -80,7 +80,7 @@ export const sortRows = ({
   rowIds.slice().sort((a, b) => {
     const cellA = cellsById[getCellId(a, key)];
     const cellB = cellsById[getCellId(b, key)];
-    return sortRow(cellA.value, cellB.value, {
+    return sortRow(cellA && cellA.value, cellB && cellB.value, {
       key,
       sortDirection,
       locale,