public function testProcessRelations()
 {
     $this->creditmemoMock->expects($this->once())->method('getId')->willReturn('creditmemo-id-value');
     $this->creditmemoMock->expects($this->exactly(2))->method('getItems')->willReturn([$this->itemMock]);
     $this->creditmemoMock->expects($this->exactly(2))->method('getComments')->willReturn([$this->commentMock]);
     $this->itemMock->expects($this->once())->method('setParentId')->with('creditmemo-id-value')->willReturnSelf();
     $this->itemResourceMock->expects($this->once())->method('save')->with($this->itemMock)->willReturnSelf();
     $this->commentResourceMock->expects($this->once())->method('save')->with($this->commentMock)->willReturnSelf();
     $this->relationProcessor->processRelation($this->creditmemoMock);
 }