fix(table): fix row hover with expanded offset rowSpan

src/Body/BodyRow.tsx

@@ -84,7 +84,8 @@ export function getCellProps<RecordType>(
     );
   }
 
-  const additionalCellProps = column.onCell?.(record, index) || {};
+  const additionalCellProps = { ...(column.onCell?.(record, index) || {}) };
+  let hoverRowSpan: number | undefined;
 
   // Expandable row has offset
   if (expandedRowOffset) {
@@ -93,6 +94,7 @@ export function getCellProps<RecordType>(
     // For expandable row with rowSpan,
     // We should increase the rowSpan if the row is expanded
     if (expandable && rowSpan && colIndex < expandedRowOffset) {
+      hoverRowSpan = rowSpan;
       let currentRowSpan = rowSpan;
 
       for (let i = index; i < index + rowSpan; i += 1) {
@@ -110,6 +112,7 @@ export function getCellProps<RecordType>(
     fixedInfo,
     appendCellNode,
     additionalCellProps: additionalCellProps,
+    hoverRowSpan,
   };
 }
 
@@ -188,7 +191,7 @@ const BodyRow = <RecordType extends { children?: readonly RecordType[] }>(
       {flattenColumns.map((column: ColumnType<RecordType>, colIndex) => {
         const { render, dataIndex, className: columnClassName } = column;
 
-        const { key, fixedInfo, appendCellNode, additionalCellProps } = getCellProps(
+        const { key, fixedInfo, appendCellNode, additionalCellProps, hoverRowSpan } = getCellProps(
           rowInfo,
           column,
           colIndex,
@@ -217,6 +220,7 @@ const BodyRow = <RecordType extends { children?: readonly RecordType[] }>(
             {...fixedInfo}
             appendNode={appendCellNode}
             additionalProps={additionalCellProps}
+            hoverRowSpan={hoverRowSpan}
           />
         );
       })}

src/Cell/index.tsx

@@ -52,6 +52,8 @@ export interface CellProps<RecordType extends DefaultRecordType> {
   /** @private Used for `expandable` with nest tree */
   appendNode?: React.ReactNode;
   additionalProps?: React.TdHTMLAttributes<HTMLTableCellElement>;
+  /** @private Keep hover range independent from layout rowSpan patched by expanded row */
+  hoverRowSpan?: number;
 
   rowType?: 'header' | 'body' | 'footer';
 
@@ -123,6 +125,7 @@ const Cell = <RecordType,>(props: CellProps<RecordType>) => {
     // Private
     appendNode,
     additionalProps = {},
+    hoverRowSpan,
     isSticky,
   } = props;
 
@@ -183,13 +186,14 @@ const Cell = <RecordType,>(props: CellProps<RecordType>) => {
   // ================ RowSpan & ColSpan =================
   const mergedColSpan = legacyCellProps?.colSpan ?? additionalProps.colSpan ?? colSpan ?? 1;
   const mergedRowSpan = legacyCellProps?.rowSpan ?? additionalProps.rowSpan ?? rowSpan ?? 1;
+  const mergedHoverRowSpan = legacyCellProps?.rowSpan ?? hoverRowSpan ?? mergedRowSpan;
 
   // ====================== Hover =======================
-  const [hovering, onHover] = useHoverState(index, mergedRowSpan);
+  const [hovering, onHover] = useHoverState(index, mergedHoverRowSpan);
 
   const onMouseEnter: React.MouseEventHandler<HTMLTableCellElement> = useEvent(event => {
     if (record) {
-      onHover(index, index + mergedRowSpan - 1);
+      onHover(index, index + mergedHoverRowSpan - 1);
     }
 
     additionalProps?.onMouseEnter?.(event);

src/VirtualTable/VirtualCell.tsx

@@ -57,7 +57,7 @@ const VirtualCell = <RecordType,>(props: VirtualCellProps<RecordType>) => {
   const { columnsOffset } = useContext(GridContext, ['columnsOffset']);
 
   // TODO: support `expandableRowOffset`
-  const { key, fixedInfo, appendCellNode, additionalCellProps } = getCellProps(
+  const { key, fixedInfo, appendCellNode, additionalCellProps, hoverRowSpan } = getCellProps(
     rowInfo,
     column,
     colIndex,
@@ -128,6 +128,7 @@ const VirtualCell = <RecordType,>(props: VirtualCellProps<RecordType>) => {
       shouldCellUpdate={column.shouldCellUpdate}
       {...fixedInfo}
       appendNode={appendCellNode}
+      hoverRowSpan={hoverRowSpan}
       additionalProps={{
         ...additionalCellProps,
         style: mergedStyle,

tests/Hover.spec.tsx

@@ -5,6 +5,7 @@ import Table from '../src';
 import type { TableProps } from '../src/Table';
 
 describe('Table.Hover', () => {
+  const hoverClassName = 'rc-table-cell-row-hover';
   const data = [
     { key: 'key0', name: 'Lucy' },
     { key: 'key1', name: 'Jack' },
@@ -127,6 +128,165 @@ describe('Table.Hover', () => {
     expect(container.querySelector('.rc-table-cell-row-hover')).toBeFalsy();
   });
 
+  it('does not let expanded row offset rowSpan affect hover range', () => {
+    const { container } = render(
+      <Table
+        rowKey="key"
+        columns={[
+          {
+            dataIndex: 'group',
+            onCell: (_, index) => {
+              if (index === 0) {
+                return { rowSpan: 2 };
+              }
+              if (index === 1) {
+                return { rowSpan: 0 };
+              }
+              return {};
+            },
+          },
+          Table.EXPAND_COLUMN,
+          {
+            dataIndex: 'name',
+          },
+        ]}
+        data={[
+          { key: 'a', group: 'Group 1', name: 'Alpha' },
+          { key: 'b', group: 'Group 1', name: 'Beta' },
+          { key: 'c', group: 'Group 2', name: 'Gamma' },
+        ]}
+        expandable={{
+          expandedRowOffset: 1,
+          expandedRowKeys: ['a'],
+          expandedRowRender: record => <span>expanded {record.key}</span>,
+        }}
+      />,
+    );
+
+    const getCell = (text: string) => {
+      const cell = Array.from(container.querySelectorAll<HTMLTableCellElement>('tbody td')).find(
+        cell => cell.textContent === text,
+      );
+      expect(cell).toBeTruthy();
+      return cell!;
+    };
+
+    const groupCell = getCell('Group 1');
+    const betaCell = getCell('Beta');
+    const gammaCell = getCell('Gamma');
+
+    expect(groupCell.getAttribute('rowspan')).toBe('3');
+
+    fireEvent.mouseEnter(groupCell);
+    expect(groupCell.classList.contains(hoverClassName)).toBe(true);
+    expect(betaCell.classList.contains(hoverClassName)).toBe(true);
+    expect(gammaCell.classList.contains(hoverClassName)).toBe(false);
+
+    fireEvent.mouseEnter(gammaCell);
+    expect(groupCell.classList.contains(hoverClassName)).toBe(false);
+    expect(gammaCell.classList.contains(hoverClassName)).toBe(true);
+  });
+
+  it('keeps legacy render rowSpan priority for hover range', () => {
+    const { container } = render(
+      <Table
+        rowKey="key"
+        columns={[
+          {
+            dataIndex: 'group',
+            render: (value, _, index) => ({
+              children: value,
+              props: { rowSpan: index === 0 ? 2 : 0 },
+            }),
+          },
+          Table.EXPAND_COLUMN,
+          {
+            dataIndex: 'name',
+          },
+        ]}
+        data={[
+          { key: 'a', group: 'Group 1', name: 'Alpha' },
+          { key: 'b', group: 'Group 1', name: 'Beta' },
+          { key: 'c', group: 'Group 2', name: 'Gamma' },
+        ]}
+        expandable={{
+          expandedRowOffset: 1,
+          expandedRowRender: record => <span>expanded {record.key}</span>,
+        }}
+      />,
+    );
+
+    const getCell = (text: string) => {
+      const cell = Array.from(container.querySelectorAll<HTMLTableCellElement>('tbody td')).find(
+        item => item.textContent === text,
+      );
+      expect(cell).toBeTruthy();
+      return cell!;
+    };
+
+    const groupCell = getCell('Group 1');
+    const alphaCell = getCell('Alpha');
+    const betaCell = getCell('Beta');
+    const gammaCell = getCell('Gamma');
+
+    expect(groupCell.getAttribute('rowspan')).toBe('2');
+
+    fireEvent.mouseEnter(groupCell);
+    expect(alphaCell.classList.contains(hoverClassName)).toBe(true);
+    expect(betaCell.classList.contains(hoverClassName)).toBe(true);
+    expect(gammaCell.classList.contains(hoverClassName)).toBe(false);
+  });
+
+  it('does not mutate stable onCell props across expanded row renders', () => {
+    const rowSpanProps = [{ rowSpan: 2 }, { rowSpan: 0 }, {}];
+    const dataSource = [
+      { key: 'a', group: 'Group 1', name: 'Alpha' },
+      { key: 'b', group: 'Group 1', name: 'Beta' },
+      { key: 'c', group: 'Group 2', name: 'Gamma' },
+    ];
+
+    const createTableWithExpandedKeys = (expandedRowKeys: React.Key[]) => (
+      <React.StrictMode>
+        <Table
+          rowKey="key"
+          columns={[
+            {
+              dataIndex: 'group',
+              onCell: (_, index) => rowSpanProps[index],
+            },
+            Table.EXPAND_COLUMN,
+            {
+              dataIndex: 'name',
+            },
+          ]}
+          data={dataSource}
+          expandable={{
+            expandedRowOffset: 1,
+            expandedRowKeys,
+            expandedRowRender: record => <span>expanded {record.key}</span>,
+          }}
+        />
+      </React.StrictMode>
+    );
+
+    const { container, rerender } = render(createTableWithExpandedKeys([]));
+    const getGroupCell = () =>
+      Array.from(container.querySelectorAll<HTMLTableCellElement>('tbody td')).find(
+        cell => cell.textContent === 'Group 1',
+      )!;
+
+    expect(rowSpanProps[0].rowSpan).toBe(2);
+    expect(getGroupCell().getAttribute('rowspan')).toBe('2');
+
+    rerender(createTableWithExpandedKeys(['a']));
+    expect(rowSpanProps[0].rowSpan).toBe(2);
+    expect(getGroupCell().getAttribute('rowspan')).toBe('3');
+
+    rerender(createTableWithExpandedKeys([]));
+    expect(rowSpanProps[0].rowSpan).toBe(2);
+    expect(getGroupCell().getAttribute('rowspan')).toBe('2');
+  });
+
   describe('perf', () => {
     it('legacy mode should render every time', () => {
       let renderTimes = 0;