fix(ag-grid): persist "None" value aggregation selection (#41386)

Co-authored-by: Enzo Martellucci <52219496+EnxDev@users.noreply.github.com>
Co-authored-by: Enzo Martellucci <enzomartellucci@gmail.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
(cherry picked from commit fb496e158a)

superset-frontend/plugins/plugin-chart-ag-grid-table/src/AgGridTable/index.tsx

@@ -57,6 +57,7 @@ import { SearchOption, SortByItem } from '../types';
 import getInitialSortState, { shouldSort } from '../utils/getInitialSortState';
 import getInitialFilterModel from '../utils/getInitialFilterModel';
 import reconcileColumnState from '../utils/reconcileColumnState';
+import getColumnStateSignature from '../utils/getColumnStateSignature';
 import { PAGE_SIZE_OPTIONS } from '../consts';
 import { getCompleteFilterState } from '../utils/filterStateManager';
 
@@ -335,11 +336,11 @@ const AgGridDataTable: FunctionComponent<AgGridTableProps> = memo(
               timestamp: Date.now(),
             };
 
-            const stateHash = JSON.stringify({
-              columnOrder: columnState.map(c => c.colId),
-              sorts: sortModel,
-              filters: filterModel,
-            });
+            const stateHash = getColumnStateSignature(
+              columnState,
+              sortModel,
+              filterModel,
+            );
 
             if (stateHash !== lastCapturedStateRef.current) {
               lastCapturedStateRef.current = stateHash;

superset-frontend/plugins/plugin-chart-ag-grid-table/src/utils/getColumnStateSignature.ts

@@ -0,0 +1,51 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+import type { ColumnState } from '@superset-ui/core/components/ThemedAgGridReact';
+
+type SortModelEntry = {
+  colId: string;
+  sort: 'asc' | 'desc';
+  sortIndex: number;
+};
+
+/**
+ * Stable signature of the persisted parts of AG Grid column state (order,
+ * value aggregation, sorts, filters), used to detect changes worth saving.
+ * `aggFunc` is normalized so the "None" option (`null`/`undefined`) produces
+ * a distinct signature instead of reverting to the default on reload.
+ */
+export default function getColumnStateSignature(
+  columnState: ColumnState[],
+  sortModel: SortModelEntry[],
+  filterModel: Record<string, unknown>,
+): string {
+  return JSON.stringify({
+    columnOrder: columnState.map(col => col.colId),
+    aggregations: columnState.map(col => ({
+      colId: col.colId,
+      // "None" (null/undefined) maps to an explicit sentinel; functions map
+      // to a fixed marker so the signature never depends on JSON.stringify
+      // dropping them (defensive: persisted aggFuncs are always strings).
+      aggFunc:
+        typeof col.aggFunc === 'function' ? 'custom' : (col.aggFunc ?? null),
+    })),
+    sorts: sortModel,
+    filters: filterModel,
+  });
+}

superset-frontend/plugins/plugin-chart-ag-grid-table/src/utils/reconcileColumnState.test.ts

@@ -84,3 +84,20 @@ test('drops stale order when a dynamic group by swaps the dimension column', ()
     ],
   });
 });
+
+test('preserves per-column aggFunc, including explicit "None" (null), through reconciliation', () => {
+  // Regression #107166: saved aggFunc must reach applyColumnState untouched.
+  const colDefs: ColDef[] = [{ field: 'name' }, { field: 'SUM(Sales_Amount)' }];
+  const savedColumnState: ColumnState[] = [
+    { colId: 'name' },
+    { colId: 'SUM(Sales_Amount)', aggFunc: null },
+  ];
+
+  expect(reconcileColumnState(savedColumnState, colDefs)).toEqual({
+    applyOrder: true,
+    columnState: [
+      { colId: 'name' },
+      { colId: 'SUM(Sales_Amount)', aggFunc: null },
+    ],
+  });
+});

superset-frontend/plugins/plugin-chart-ag-grid-table/test/utils/getColumnStateSignature.test.ts

@@ -0,0 +1,82 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+import type { ColumnState } from '@superset-ui/core/components/ThemedAgGridReact';
+import getColumnStateSignature from '../../src/utils/getColumnStateSignature';
+
+const filterModel = {};
+
+test('signature changes when a column value aggregation changes', () => {
+  const before = getColumnStateSignature(
+    [{ colId: 'sales', aggFunc: 'sum' }],
+    [],
+    filterModel,
+  );
+  const after = getColumnStateSignature(
+    [{ colId: 'sales', aggFunc: 'avg' }],
+    [],
+    filterModel,
+  );
+  expect(after).not.toEqual(before);
+});
+
+test('switching value aggregation to "None" (null/undefined) changes the signature', () => {
+  // Regression #107166: "None" must be captured so it persists on reload.
+  const sumState = getColumnStateSignature(
+    [{ colId: 'sales', aggFunc: 'sum' }],
+    [],
+    filterModel,
+  );
+  const noneNull = getColumnStateSignature(
+    [{ colId: 'sales', aggFunc: null }],
+    [],
+    filterModel,
+  );
+  const noneUndefined = getColumnStateSignature(
+    [{ colId: 'sales' }],
+    [],
+    filterModel,
+  );
+
+  expect(noneNull).not.toEqual(sumState);
+  expect(noneUndefined).not.toEqual(sumState);
+  // null and undefined both represent "None" and must be treated identically.
+  expect(noneNull).toEqual(noneUndefined);
+});
+
+test('signature is stable when nothing changes', () => {
+  const columnState: ColumnState[] = [{ colId: 'sales', aggFunc: 'sum' }];
+  const a = getColumnStateSignature(columnState, [], filterModel);
+  const b = getColumnStateSignature([...columnState], [], filterModel);
+  expect(a).toEqual(b);
+});
+
+test('a function aggFunc is distinguishable from "None"', () => {
+  // Pins the defensive marker: function aggFuncs stay distinct from "None".
+  const customAgg = getColumnStateSignature(
+    [{ colId: 'sales', aggFunc: () => 42 }],
+    [],
+    filterModel,
+  );
+  const none = getColumnStateSignature(
+    [{ colId: 'sales', aggFunc: null }],
+    [],
+    filterModel,
+  );
+  expect(customAgg).not.toEqual(none);
+});