test(DataGrid): add unit tests for utils

Author: dmirgaev

packages/devextreme/js/__internal/grids/grid_core/columns_resizing_reordering/m_columns_resizing_reordering.ts

@@ -1436,7 +1436,7 @@ export class DraggingHeaderViewController extends modules.ViewController {
    * @param columns All columns in the given location
    * @param location Location where we move column (headers, group, column chooser, etc.)
    * @param sourceColumn Column that is dragging
-   * @param cells collection of draggable cells wrapped into jQuery object
+   * @param cells JQuery-wrapped collection of header cell elements
    * @returns whether to filter current point (true - remove point, false - keep it)
    */
 

packages/devextreme/js/__internal/grids/grid_core/columns_resizing_reordering/utils.test.ts

@@ -0,0 +1,74 @@
+import { describe, expect, it } from '@jest/globals';
+
+import { getDraggingPanelBoundingRects } from './utils';
+
+const getRandomPoint = (max: number) => Math.floor(Math.random() * max);
+
+const getDraggingPanelMock = () => ({
+  getBoundingRect: () => ({
+    top: getRandomPoint(1080),
+    bottom: getRandomPoint(1080),
+    left: getRandomPoint(1920),
+    right: getRandomPoint(1920),
+  }),
+} as any);
+
+describe('m_columns_resizing_reordering/utils.test.ts', () => {
+  describe('getDraggingPanelBoundingRects', () => {
+    it('returns equal amount of elements in tuple', () => {
+      const draggingPanels = [
+        getDraggingPanelMock(),
+        getDraggingPanelMock(),
+        getDraggingPanelMock(),
+      ];
+      const result = getDraggingPanelBoundingRects(draggingPanels);
+
+      expect(result?.length).toBe(draggingPanels.length);
+    });
+
+    it('returns the same dragging panel objects', () => {
+      const draggingPanels = [
+        getDraggingPanelMock(),
+        getDraggingPanelMock(),
+        getDraggingPanelMock(),
+      ];
+      const result = getDraggingPanelBoundingRects(draggingPanels);
+
+      expect(result).not.toBeNull();
+      result?.forEach((draggingPanelBoundingRect, index) => {
+        expect(draggingPanelBoundingRect.draggingPanel).toBe(draggingPanels[index]);
+      });
+    });
+
+    it('returns filtered tuple without empty objects', () => {
+      const draggingPanels = [
+        getDraggingPanelMock(),
+        undefined,
+        getDraggingPanelMock(),
+        null,
+      ];
+      const result = getDraggingPanelBoundingRects(draggingPanels);
+
+      expect(result?.length).toBe(draggingPanels.filter(Boolean).length);
+    });
+
+    it('returns null if the result is empty array', () => {
+      const draggingPanels = [undefined, null] as any[];
+      const result = getDraggingPanelBoundingRects(draggingPanels);
+
+      expect(result).toBeNull();
+    });
+
+    it('returns null if draggingPanels array is empty', () => {
+      const draggingPanels = [] as any[];
+      const result = getDraggingPanelBoundingRects(draggingPanels);
+
+      expect(result).toBeNull();
+    });
+
+    it('returns null if draggingPanels is null or undefined', () => {
+      expect(getDraggingPanelBoundingRects(undefined as any)).toBeNull();
+      expect(getDraggingPanelBoundingRects(null as any)).toBeNull();
+    });
+  });
+});