public function testElementOperations() { $buttonElement = $this->getMockBuilder('Magento\\Framework\\Data\\Form\\Element\\Button')->disableOriginalConstructor()->getMock(); $buttonElement->expects($this->any())->method('getId')->will($this->returnValue('1')); $buttonElement->expects($this->any())->method('getName')->will($this->returnValue('Hero')); $this->_form->addElement($buttonElement); $this->_form->addElementToCollection($buttonElement); $this->_form->addValues(['1', '2', '3']); $this->_form->setValues(['4', '5', '6']); $this->_form->addFieldNameSuffix('abc123'); $this->_form->removeField($buttonElement->getId()); $this->assertSame($this->_form->checkElementId($buttonElement->getId()), true); }