TreeView: provide a way to control ability to select nodes

[pharret31]

No description provided.

[Copilot]

Pull request overview

Adds a new TreeView option to control whether disabled nodes participate in checkbox selection logic, and introduces test coverage for the new selection behavior.

Changes:

• Added disabledNodeSelectionMode option to TreeView base and wired it into the hierarchical data adapter.
• Updated selection propagation and “select all” state calculation to optionally skip disabled nodes.
• Added QUnit coverage for initial state, selectAll/unselectAll, runtime option changes, and recursive selection scenarios.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 6 comments.

File	Description
packages/devextreme/testing/tests/DevExpress.ui.widgets/treeView.checkboxes.tests.js	Adds tests validating selection/aria-checked behavior for the new mode.
packages/devextreme/js/__internal/ui/tree_view/tree_view.base.ts	Adds the new option, default value, option change handling, and passes it to the data adapter.
packages/devextreme/js/__internal/ui/hierarchical_collection/data_converter.ts	Tracks disabled items count to support “select all” state computation.
packages/devextreme/js/__internal/ui/hierarchical_collection/data_adapter.ts	Implements skip-disabled selection logic in recursive selection and selectAll/isAllSelected.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 5 comments.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

[Copilot]

There is an inconsistency between selectAll() behavior and recursive selectItem() behavior when disabledNodeSelectionMode='never'.

When selectAll() is called, it iterates through all nodes (line 570) and selects all enabled nodes, including children of disabled nodes (as shown in test at line 594 in treeView.checkboxes.tests.js).

However, when selectItem(parentKey) is called with recursiveSelection=true, the _iterateChildren method has an early return (lines 251-253) that prevents iterating into children of disabled nodes. This means children of disabled nodes won't be selected when selecting their grandparent.

This inconsistency is demonstrated in the tests:

• Test at line 594: selectAll() with mode='never' DOES select children of disabled nodes
• Test at line 633: selectItem(parentId) with mode='never' does NOT select children of disabled nodes

Consider removing the early return at lines 251-253 to make the behavior consistent, or add clear documentation explaining why these two operations behave differently.

Suggested change

	if (this.options.disabledNodeSelectionMode === 'never' && this._isNodeDisabled(node)) {
	return;
	}