public function testExecuteEmptyQuoteError()
{
$resultExpectation = ['success' => false, 'error' => true, 'error_messages' => __('Your payment has been declined. Please try again.')];
$quoteMock = null;
$jsonMock = $this->getMockBuilder('Magento\\Framework\\Controller\\Result\\Json')->disableOriginalConstructor()->getMock();
$this->sessionManagerMock->expects($this->atLeastOnce())->method('getQuote')->willReturn($quoteMock);
$this->resultJsonFactoryMock->expects($this->once())->method('create')->willReturn($jsonMock);
$jsonMock->expects($this->once())->method('setData')->with($resultExpectation)->willReturnSelf();
$this->assertEquals($jsonMock, $this->controller->executeInternal());
}