GridCore dataController: fix ESLint errors in the updateItems block

[Alyar666]

No description provided.

[Copilot]

Pull request overview

This PR refactors the GridCore DataController “partial refresh” path (the applyChangesOnly / row-index correction flow) to address ESLint issues while improving type safety and extracting reusable row-change utilities.

Changes:

• Renamed internal extensibility hooks from _applyChangesOnly / _correctRowIndices to applyChangesOnly / correctRowIndices and updated all overrides.
• Refactored DataController.applyChangesOnly into smaller helpers and moved key/index/cell-update logic into utils/row_changes.ts.
• Expanded Jest coverage for the extracted row_changes utilities and introduced supporting types (RowIndexByKey, ItemChange).

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/devextreme/js/__internal/grids/grid_core/keyboard_navigation/m_keyboard_navigation.ts	Updates the keyboard-navigation extender override to the renamed correctRowIndices hook.
packages/devextreme/js/__internal/grids/grid_core/editing/m_editing.ts	Updates the editing extender override to the renamed applyChangesOnly hook.
packages/devextreme/js/__internal/grids/grid_core/data_controller/utils/row_changes.ts	Extracts and adds helper utilities for row keying, indexing, cell updater propagation, and change conversion.
packages/devextreme/js/__internal/grids/grid_core/data_controller/utils/tests/row_changes.test.ts	Adds unit tests for the newly extracted row-change helpers.
packages/devextreme/js/__internal/grids/grid_core/data_controller/types.ts	Adds new helper types (RowIndexByKey, ItemChange) used by the refactored update logic.
packages/devextreme/js/__internal/grids/grid_core/data_controller/data_controller.ts	Refactors the partial-update (“repaint changes only”) refresh path, improves typing, and updates insert-index correction logic.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

Suppressed comments (1)

packages/devextreme/js/__internal/grids/grid_core/data_controller/utils/row_changes.ts:80

• getDataRowIndex allocates intermediate arrays (slice + filter) every time it runs. This method is called from changingHandler for each inserted change and can run on large visible-row sets; a simple counted loop avoids allocations and should be measurably cheaper while still satisfying no-plusplus by using += 1.

export function getDataRowIndex(rows: ProcessedItem[], visibleRowIndex: number): number {
  const previousRows = rows.slice(0, visibleRowIndex);

  return previousRows.filter((row) => row?.rowType === 'data' || row?.rowType === 'group').length;
}

[anna-shakhova]

Suggested change

	export function getDataRowIndex(rows: ProcessedItem[], visibleRowIndex: number): number {
	export function getDataRowCount(rows: ProcessedItem[], visibleRowIndex: number): number {

[anna-shakhova]

'convert' reads as we passed smth and return converted one, not mutate.
can we avoid mutation here?

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

Suppressed comments (1)

packages/devextreme/js/__internal/grids/grid_core/data_controller/utils/row_changes.ts:80

• getDataRowIndex allocates intermediate arrays (slice + filter) on every call. This runs in the dataSource changing handler and can be invoked frequently for large grids, so avoiding allocations here helps prevent unnecessary GC pressure.

export function getDataRowIndex(rows: ProcessedItem[], visibleRowIndex: number): number {
  const previousRows = rows.slice(0, visibleRowIndex);

  return previousRows.filter((row) => row?.rowType === 'data' || row?.rowType === 'group').length;
}