public function testExecute()
{
$searchString = "simple";
$firstItemMock = $this->getMockBuilder('Magento\\Search\\Model\\Autocomplete\\Item')->disableOriginalConstructor()->setMockClassName('FirstItem')->setMethods(['toArray'])->getMock();
$secondItemMock = $this->getMockBuilder('Magento\\Search\\Model\\Autocomplete\\Item')->disableOriginalConstructor()->setMockClassName('SecondItem')->setMethods(['toArray'])->getMock();
$this->request->expects($this->once())->method('getParam')->with('q')->will($this->returnValue($searchString));
$this->autocomplete->expects($this->once())->method('getItems')->will($this->returnValue([$firstItemMock, $secondItemMock]));
$this->resultJsonMock->expects($this->once())->method('setData')->willReturnSelf();
$this->assertSame($this->resultJsonMock, $this->controller->execute());
}
