fix: address deferred minor review findings — doc accuracy, redundant casts, rowMeta in edit params, stable empty map, role=status

- docs: soften inaccurate "TypeScript compile error" claim in grid-row-meta.md and row.md; _hasChildren resolves to unknown, not a compile error
- docs: replace `as any` cast in migration example with `as Record<string, unknown>`
- docs: narrow pagination localeText coverage claim — ARIA labels and button titles remain hardcoded
- Cell: remove 3 redundant `as React.ReactNode` casts (renderCell, renderEditCell, formattedValue)
- Cell: pass rowMeta to renderEditCell params (was already passed to renderCell)
- types: drop redundant Partial<> wrapper on localeText (all GridLocaleText fields are already optional)
- DataGrid: hoist fallback rowMetaMap to module-level EMPTY_ROW_META_MAP for stable identity on flat grids
- CellErrorBoundary: change role="alert" to role="status" (polite live region; avoids N simultaneous interruptions)
- tests: add ArrowDown-at-last-row boundary test to useGridKeyboardNavigation
- demo: update Advanced Charts Integration badge from Q2 2026 to Q1 2027

Author: Asif Ansari

demo/Home.tsx

@@ -50,7 +50,7 @@ export default function Home(_props: HomeProps) {
     ];
 
     const comingSoon = [
-        { badge: 'Q2 2026', name: 'Advanced Charts Integration', desc: 'Native sparklines and trend charts directly inside grid cells.' },
+        { badge: 'Q1 2027', name: 'Advanced Charts Integration', desc: 'Native sparklines and trend charts directly inside grid cells.' },
         { badge: 'Q3 2026', name: 'Interactive Pivot Builder', desc: 'Intuitive drag-and-drop interface for end-user analytics.' },
         { badge: 'Q4 2026', name: 'Native PDF Reporting', desc: 'Automated PDF generation with customizable layouts.' }
     ];

docs/architecture/grid-row-meta.md

@@ -66,7 +66,7 @@ renderCell: (params) => {
 
 ## Runtime shim (v1.1 only)
 
-The underscore fields (`_hasChildren`, `_treeDepth`, etc.) continue to be injected onto the row object at runtime in v1.1. They are no longer declared on `GridRowModel`, so TypeScript strict-mode users get a compile error when accessing them. JS users or users who cast with `as any` see no change.
+The underscore fields (`_hasChildren`, `_treeDepth`, etc.) continue to be injected onto the row object at runtime in v1.1. They are no longer declared on `GridRowModel`; because `GridRowModel` retains `[key: string]: unknown`, accessing `params.row._hasChildren` resolves to `unknown` rather than producing a TypeScript compile error. Assignment to a typed variable (e.g. `const x: boolean = params.row._hasChildren`) and arithmetic will error; truthiness checks will not. Migrate to `params.rowMeta?.hasChildren` for the typed path.
 
 **The runtime injection will be removed in v2.0.** Migrate to `params.rowMeta` before upgrading to v2.
 

docs/components/pagination.md

@@ -35,7 +35,7 @@ You can replace the internal pagination UI using the `pagination` slot:
 
 ## 🌍 Internationalisation
 
-Pass `localeText` on `<DataGrid />` to override all user-visible strings in the Pagination component:
+Pass `localeText` on `<DataGrid />` to override the text labels in the Pagination component (rows-per-page, range, and page-counter labels). Note: ARIA labels (`aria-label="Pagination"`, `aria-label="Rows per page"`) and button titles (`title="Previous page"`, `title="Next page"`) are currently hardcoded and not overrideable via `localeText`.
 
 | Key | Type | Default |
 | :--- | :--- | :--- |

docs/components/row.md

@@ -34,11 +34,12 @@ When `getDetailPanelContent` is provided, the `<Row />` renders an expandable co
 
 The internal hierarchy fields (`_hasChildren`, `_treeDepth`, `_isExpanded`, `_groupingField`, `_groupingValue`, `_descendantCount`, `_isGroupRow`) are no longer typed on `GridRowModel`. They will be removed from the runtime row object in v2.0.
 
-**Before (still works at runtime in v1.1, TypeScript compile error in strict mode):**
+**Before (still works at runtime in v1.1 — `params.row._hasChildren` is `unknown`, not `boolean`; assignment to typed variables and arithmetic will error, truthiness checks will not):**
 
 ```tsx
 renderCell: (params) => {
-  const hasChildren = (params.row as any)._hasChildren;
+  // v1.1 accepts this at runtime; _hasChildren resolves to unknown via [key: string]: unknown
+  const hasChildren = (params.row as Record<string, unknown>)._hasChildren;
   return hasChildren ? <GroupIcon /> : params.value;
 }
 ```

lib/components/Cell/Cell.tsx

@@ -222,8 +222,9 @@ function CellImpl<R extends GridRowModel = GridRowModel>(props: CellProps<R>) {
                             field: colDef.field,
                             colDef,
                             rowIndex,
-                            colIndex
-                        }) as React.ReactNode
+                            colIndex,
+                            rowMeta,
+                        })
                     ) : (
                         <GridEditInputCell
                             value={value}
@@ -247,10 +248,10 @@ function CellImpl<R extends GridRowModel = GridRowModel>(props: CellProps<R>) {
                             rowIndex,
                             colIndex,
                             rowMeta,
-                        }) as React.ReactNode}
+                        })}
                     </CellErrorBoundary>
                 ) : (
-                    formattedValue as React.ReactNode
+                    formattedValue
                 )}
             </div>
         </div>

lib/components/Cell/CellErrorBoundary.tsx

@@ -40,7 +40,7 @@ export class CellErrorBoundary extends React.Component<CellErrorBoundaryProps, C
             return (
                 <div
                     className="ogx__cell-error"
-                    role="alert"
+                    role="status"
                     aria-label={`Error in cell: ${this.props.field}`}
                     title={this.state.error?.message ?? 'Render error'}
                 >

lib/components/DataGrid/DataGrid.tsx

@@ -29,6 +29,8 @@ import { GridVirtualRows } from './GridVirtualRows';
 import { GridStandaloneColumnPanel } from './GridStandaloneColumnPanel';
 import type { DataGridProps, GridRowModel, GridRowId, GridSortDirection, GridColDef, GridRowParams, GridCellParams, GridDataSource, GridAggregationResult, GridFilterModel, GridTreeNode, GridSortItem, GridRowMeta } from '../../types';
 
+const EMPTY_ROW_META_MAP: Map<GridRowId, GridRowMeta> = new Map();
+
 export function DataGrid<R extends GridRowModel = GridRowModel>(props: DataGridProps<R>) {
     const {
         rows,
@@ -339,7 +341,7 @@ export function DataGrid<R extends GridRowModel = GridRowModel>(props: DataGridP
     const rowMetaMap = useMemo<Map<GridRowId, GridRowMeta>>(() => {
         if (isTreeData) return treeDataHandlers.rowMetaMap;
         if (isRowGrouping) return rowGroupingHandlers.rowMetaMap;
-        return new Map();
+        return EMPTY_ROW_META_MAP;
     }, [isTreeData, treeDataHandlers.rowMetaMap, isRowGrouping, rowGroupingHandlers.rowMetaMap]);
 
     const pagination = propPagination && !isRowGrouping;

lib/hooks/core/useGridKeyboardNavigation.test.ts

@@ -86,6 +86,15 @@ describe('useGridKeyboardNavigation — arrow keys', () => {
         expect(result.current.focusedCell?.id).toBe('HEADER');
     });
 
+    it('ArrowDown at last row — no change', () => {
+        const { result } = renderHook(() => useGridKeyboardNavigation(BASE_PARAMS));
+        // ROWS has 3 entries; last row id is 3
+        const lastRow = ROWS[ROWS.length - 1];
+        act(() => { result.current.setFocusedCell({ id: lastRow.id, field: 'name' }); });
+        act(() => { result.current.handleKeyDown(keyEvent('ArrowDown')); });
+        expect(result.current.focusedCell?.id).toBe(lastRow.id);
+    });
+
     it('ArrowRight moves focusedCell to next column', () => {
         const { result } = renderHook(() => useGridKeyboardNavigation(BASE_PARAMS));
         act(() => { result.current.setFocusedCell({ id: 1, field: 'name' }); });

lib/types/index.ts

@@ -580,7 +580,7 @@ export interface DataGridProps<R extends GridRowModel = GridRowModel> {
   /** Message displayed when there are no rows to show. */
   noRowsLabel?: string;
   /** Overrides for user-visible strings (i18n). All fields are optional. */
-  localeText?: Partial<GridLocaleText>;
+  localeText?: GridLocaleText;
 
   /** Advanced: The starting internal state of the grid. */
   initialState?: import('../state/types').GridInitialState;