DataGrid - Summary values in the fixed column disappear when virtual …

…scrolling and grouping are used (T1221369) (#27642)

Co-authored-by: williamvinogradov <[email protected]>

e2e/testcafe-devextreme/tests/dataGrid/virtualColumns.ts

@@ -288,3 +288,63 @@ test('Columns should be rendered correctly after reinit of columns controller',
     columnRenderingMode: 'virtual',
   },
 }));
+
+test('Group row should have right colspan with summary, virtual columns and fixed columns (T1221369)', async (t) => {
+  const grid = new DataGrid('#container');
+  const { takeScreenshot, compareResults } = createScreenshotsComparer(t);
+
+  await takeScreenshot('T1221369_fixed-summary-with-virtual-cols_0.png', grid.element);
+
+  // NOTE: There is an issue with Scrollable
+  // So, we should scroll two times to reach maximum right scroll position
+  await grid.scrollTo(t, { x: 10000 });
+  await grid.scrollTo(t, { x: 10000 });
+
+  await takeScreenshot('T1221369_fixed-summary-with-virtual-cols_1.png', grid.element);
+
+  await grid.scrollTo(t, { x: 0 });
+
+  await takeScreenshot('T1221369_fixed-summary-with-virtual-cols_2.png', grid.element);
+
+  await t.expect(compareResults.isValid())
+    .ok(compareResults.errorMessages());
+}).before(async () => {
+  const generatedColumns = generateColumns(20);
+  const columns = [
+    {
+      ...generatedColumns[0],
+      groupIndex: 0,
+    },
+    {
+      ...generatedColumns[1],
+      fixed: true,
+    },
+    {
+      ...generatedColumns[2],
+      fixed: true,
+    },
+    ...generatedColumns.splice(3),
+  ];
+  const data = generateData(10, 20);
+
+  await createWidget('dxDataGrid', {
+    dataSource: data,
+    width: 400,
+    height: 400,
+    columns,
+    columnFixing: {
+      enabled: true,
+    },
+    columnMinWidth: 100,
+    scrolling: {
+      columnRenderingMode: 'virtual',
+    },
+    summary: {
+      groupItems: [{
+        column: columns[2].dataField,
+        summaryType: 'count',
+        alignByColumn: true,
+      }],
+    },
+  });
+});

packages/devextreme/js/__internal/grids/grid_core/column_fixing/m_column_fixing.ts

@@ -114,19 +114,19 @@ const baseFixedColumns = <T extends ModuleType<ColumnsView>>(Base: T) => class B
     }
   }
 
-  private _partialUpdateFixedTable(fixedColumns) {
+  private _partialUpdateFixedTable(fixedColumns, rows) {
     const fixedTableElement = this._fixedTableElement;
     const $rows = this._getRowElementsCore(fixedTableElement);
     const $colgroup = fixedTableElement.children('colgroup');
 
     $colgroup.replaceWith(this._createColGroup(fixedColumns));
 
-    for (let i = 0; i < $rows.length; i++) {
-      this._partialUpdateFixedRow($($rows[i]), fixedColumns);
+    for (let i = 0; i < rows.length; i++) {
+      this._partialUpdateFixedRow($($rows[i]), fixedColumns, rows[i]);
     }
   }
 
-  private _partialUpdateFixedRow($row, fixedColumns) {
+  private _partialUpdateFixedRow($row, fixedColumns, row) {
     const cellElements = $row.get(0).childNodes;
     const transparentColumnIndex = getTransparentColumnIndex(fixedColumns);
     const transparentColumn = fixedColumns[transparentColumnIndex];
@@ -144,11 +144,23 @@ const baseFixedColumns = <T extends ModuleType<ColumnsView>>(Base: T) => class B
     if ($row.hasClass(GROUP_ROW_CLASS)) {
       // @ts-expect-error RowsView's method
       groupCellOptions = this._getGroupCellOptions({
-        row: $row.data('options'),
+        row,
         columns: this._columnsController.getVisibleColumns(),
       });
 
-      colspan = groupCellOptions.colspan - Math.max(0, cellElements.length - (groupCellOptions.columnIndex + 2));
+      const hasSummary = row.summaryCells.length > 0;
+      if (hasSummary) {
+        // @ts-expect-error RowsView's method
+        const alignByColumnCellCount = this._getAlignByColumnCellCount(groupCellOptions.colspan, {
+          columns: this._columnsController.getVisibleColumns(),
+          row,
+          isFixed: true,
+        });
+
+        colspan = groupCellOptions.colspan - alignByColumnCellCount;
+      } else {
+        colspan = groupCellOptions.colspan - Math.max(0, cellElements.length - (groupCellOptions.columnIndex + 2));
+      }
     }
 
     for (let j = 0; j < cellElements.length; j++) {
@@ -180,7 +192,7 @@ const baseFixedColumns = <T extends ModuleType<ColumnsView>>(Base: T) => class B
       this._isFixedTableRendering = true;
 
       if (needPartialUpdate && this.option('scrolling.legacyMode') !== true) {
-        this._partialUpdateFixedTable(fixedColumns);
+        this._partialUpdateFixedTable(fixedColumns, options?.change?.items);
         this._isFixedTableRendering = false;
       } else {
         const columnIndices = change?.columnIndices;
@@ -301,14 +313,14 @@ const baseFixedColumns = <T extends ModuleType<ColumnsView>>(Base: T) => class B
         if (options.row.summaryCells && options.row.summaryCells.length) {
           const columns = this._columnsController.getVisibleColumns();
           // @ts-expect-error DataGrid's method
-          const alignByFixedColumnCellCount = this._getAlignByColumnCellCount
-            // @ts-expect-error DataGrid's method
-            ? this._getAlignByColumnCellCount(column.colspan, {
+          const alignByFixedColumnCellCount = this._getAlignByColumnCellCount?.(
+            column.colspan,
+            {
               columns,
               row: options.row,
               isFixed: true,
-            })
-            : 0;
+            },
+          ) ?? 0;
 
           if (alignByFixedColumnCellCount > 0) {
             const transparentColumnIndex = getTransparentColumnIndex(this._columnsController.getFixedColumns());