PHPUnit: Method in mocked abstract class returns null

Question

I'm writing tests against the following class:

abstract class EmailMessageRecipient
{
    private $_address = null;

    public function setAddress($address)
    {
        $this->_address = $address;
        return $this;
    }

    public function getAddress()
    {
        return $this->_address;
    }

}

The test looks like this:

class EmailMessageRecipientTest extends PHPUnit_Framework_TestCase
{
    private $_test_object;

    protected function makeTestObject()
    {
        return $this->createMock(EmailMessageRecipient::class);
    }

    public function setUp()
    {
        $this->_test_object = $this->makeTestObject();
    }

    public function testAddress()
    {
        $this->_test_object->setAddress('blah@example.com');
        $this->assertEquals('blah@example.com', $this->_test_object->getAddress());
    }
}

PHPUnit fails the test with the message Failed asserting that null matches expected 'blah@example.com'.. So $this->_test_object->getAddress() is returning null instead of the email address that was passed to it. Why is this happening and how do I adjust the test so that it passes.

Mocking the setAddress() and getAddress() methods is not an acceptable answer. The purpose of this test is to cover setAddress() and getAddress().

Related: https://stackoverflow.com/q/190295/457268 – k0pernikus Oct 23 '17 at 16:25 — k0pernikus, Oct 23 '17 at 16:25

score 1 · Accepted Answer · answered Oct 23 '17 at 16:24

If you test an abstract class you should use: getMockForAbstractClass:

The getMockForAbstractClass() method returns a mock object for an abstract class. All abstract methods of the given abstract class are mocked. This allows for testing the concrete methods of an abstract class.

Example 9.19: Testing the concrete methods of an abstract class
<?php
use PHPUnit\Framework\TestCase;

abstract class AbstractClass
{
    public function concreteMethod()
    {
        return $this->abstractMethod();
    }

    public abstract function abstractMethod();
}

class AbstractClassTest extends TestCase
{
    public function testConcreteMethod()
    {
        $stub = $this->getMockForAbstractClass(AbstractClass::class);

        $stub->expects($this->any())
             ->method('abstractMethod')
             ->will($this->returnValue(true));

        $this->assertTrue($stub->concreteMethod());
    }
}
?>

PHPUnit: Method in mocked abstract class returns null

1 Answers1

Example 9.19: Testing the concrete methods of an abstract class