@Test
public void perform_HeaderCellsSelected() {

    when(scenarioGridModelMock.getSelectedCells()).thenReturn(Collections.emptyList());
    when(scenarioGridModelMock.getSelectedHeaderCells()).thenReturn(Arrays.asList(selectedCell, selectedCell2));
    handler.perform(scenarioGridMock, false, false);
    verify(scenarioContextMenuRegistry, times(1)).manageRightClick(eq(scenarioGridMock), eq(0), eq(0), anyInt(), anyInt(), eq(true));
}