refactor(Table): address PR feedback for indeterminate checkbox

- Refactor SelectColumn to reduce duplication by building checkboxProps from commonProps
- Update example description to match PatternFly tone and emphasize accessibility
- Add comprehensive unit tests for isIndeterminate prop in Th component

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: rhamilto

packages/react-table/src/components/Table/SelectColumn.tsx

@@ -44,22 +44,18 @@ export const SelectColumn: React.FunctionComponent<SelectColumnProps> = ({
     onSelect && onSelect(event);
   };
 
-  // PatternFly Checkbox supports indeterminate via isChecked: null
-  const checkboxProps = {
-    ...props,
-    id,
-    ref: inputRef,
-    onChange: handleChange,
-    ...(isIndeterminate && { isChecked: null })
-  };
-
   const commonProps = {
     ...props,
     id,
     ref: inputRef,
     onChange: handleChange
   };
 
+  const checkboxProps = {
+    ...commonProps,
+    ...(isIndeterminate && { isChecked: null })
+  };
+
   const content = (
     <Fragment>
       {selectVariant === RowSelectVariant.checkbox ? (

packages/react-table/src/components/Table/__tests__/Th.test.tsx

@@ -54,3 +54,26 @@ test('Additional content renders after children when additionalContent is passed
   expect(thChildren.item(0)?.textContent).toEqual('Test');
   expect(thChildren.item(1)?.textContent).toEqual('Extra');
 });
+
+test('Renders checkbox without indeterminate state by default', () => {
+  render(<Th select={{ onSelect: jest.fn(), isSelected: false }} aria-label="Select all" />);
+
+  const checkbox = screen.getByRole('checkbox') as HTMLInputElement;
+  expect(checkbox).not.toBeChecked();
+  expect(checkbox.indeterminate).toBe(false);
+});
+
+test('Renders checkbox with indeterminate state when isIndeterminate is true', () => {
+  render(<Th select={{ onSelect: jest.fn(), isSelected: false, isIndeterminate: true }} aria-label="Select all" />);
+
+  const checkbox = screen.getByRole('checkbox') as HTMLInputElement;
+  expect(checkbox.indeterminate).toBe(true);
+});
+
+test('Renders checked checkbox when isSelected is true and isIndeterminate is false', () => {
+  render(<Th select={{ onSelect: jest.fn(), isSelected: true, isIndeterminate: false }} aria-label="Select all" />);
+
+  const checkbox = screen.getByRole('checkbox') as HTMLInputElement;
+  expect(checkbox).toBeChecked();
+  expect(checkbox.indeterminate).toBe(false);
+});

packages/react-table/src/components/Table/examples/Table.md

@@ -160,7 +160,7 @@ checking checkboxes will check intermediate rows' checkboxes.
 
 ### Selectable with indeterminate state
 
-This example demonstrates the indeterminate state support for the select-all checkbox. When some (but not all) rows are selected, the header checkbox displays a dash/minus icon to indicate partial selection.
+To indicate partial selection, use `isIndeterminate` on the header's `select` prop. When some (but not all) selectable rows are selected, the header checkbox will convey this information to assistive technologies and also display a dash instead of a checkmark.
 
 ```ts file="TableSelectableIndeterminate.tsx"