public function testGetItemsCollectionWithId()
{
$id = 1;
$this->creditmemo->setId($id);
$items = [];
$itemMock = $this->getMockBuilder('\\Magento\\Sales\\Model\\Order\\Creditmemo\\Item')->disableOriginalConstructor()->getMock();
$itemMock->expects($this->once())->method('setCreditmemo')->with($this->creditmemo);
$items[] = $itemMock;
/** @var ItemCollection|\PHPUnit_Framework_MockObject_MockObject $itemCollectionMock */
$itemCollectionMock = $this->getMockBuilder('\\Magento\\Sales\\Model\\ResourceModel\\Order\\Creditmemo\\Item\\Collection')->disableOriginalConstructor()->getMock();
$itemCollectionMock->expects($this->once())->method('setCreditmemoFilter')->with($id)->will($this->returnValue($items));
$this->cmItemCollectionFactoryMock->expects($this->any())->method('create')->will($this->returnValue($itemCollectionMock));
$itemsCollection = $this->creditmemo->getItemsCollection();
$this->assertEquals($items, $itemsCollection);
}
