如何使用 PHPUnit 在 Symfony2 中设置数据库密集型单元测试?

They provide this example for a service test:

服务类:

use DoctrineCommonPersistenceObjectManager;

class SalaryCalculator
{
    private $entityManager;

    public function __construct(ObjectManager $entityManager)
    {
        $this->entityManager = $entityManager;
    }

    public function calculateTotalSalary($id)
    {
        $employeeRepository = $this->entityManager
            ->getRepository('AppBundle:Employee');
        $employee = $employeeRepository->find($id);

        return $employee->getSalary() + $employee->getBonus();
    }
}

服务测试类:

namespace TestsAppBundleSalary;

use AppBundleSalarySalaryCalculator;
use AppBundleEntityEmployee;
use DoctrineORMEntityRepository;
use DoctrineCommonPersistenceObjectManager;

class SalaryCalculatorTest extends PHPUnit_Framework_TestCase
{
    public function testCalculateTotalSalary()
    {
        // First, mock the object to be used in the test
        $employee = $this->getMock(Employee::class);
        $employee->expects($this->once())
            ->method('getSalary')
            ->will($this->returnValue(1000));
        $employee->expects($this->once())
            ->method('getBonus')
            ->will($this->returnValue(1100));

        // Now, mock the repository so it returns the mock of the employee
        $employeeRepository = $this
            ->getMockBuilder(EntityRepository::class)
            ->disableOriginalConstructor()
            ->getMock();
        $employeeRepository->expects($this->once())
            ->method('find')
            ->will($this->returnValue($employee));

        // Last, mock the EntityManager to return the mock of the repository
        $entityManager = $this
            ->getMockBuilder(ObjectManager::class)
            ->disableOriginalConstructor()
            ->getMock();
        $entityManager->expects($this->once())
            ->method('getRepository')
            ->will($this->returnValue($employeeRepository));

        $salaryCalculator = new SalaryCalculator($entityManager);
        $this->assertEquals(2100, $salaryCalculator->calculateTotalSalary(1));
    }
}

这种测试不需要测试数据库，只需要模拟.