phpunit: mock object not fooling php - oop

Question

I'm going through the zend tutorials and I am testing a class with a mock object with phpunit. When I pass a mock created from Zend\Db\TableGateway to my class, who's constructor expects a Zend\Db\TableGateway, I get an type error:
"...Argument 1 passed to Album\Model\AlbumTable::__construct() must be an instance of Zend\Db\TableGateway\TableGateway, instance of Mock_TableGateway_65b55cb0 given..."
Is this supposed happen? Are phpunit mock objects supposed to be able to "fool" the class?
Here is the real class:
class AlbumTable {
protected $tableGateway;
public function __construct(TableGateway $tableGateway) {
$this->tableGateway = $tableGateway;
}
public function fetchAll() {
$resultSet = $this->tableGateway->select();
return $resultSet;
}
public function getAlbum($id){
$id = (int) $id;
$rowset = $this->tableGateway->select(array('id' => $id));
$row = $rowset->current();
if(!$row) {
throw new \Exception("Couldn't find row: $id");
}
return $row;
}
public function saveAlbum(Album $album) {
$data = array(
'artist' => $album->artist,
'title' => $album->title,
);
$id = (int)$album->id;
if ($id == 0) {
$this->tableGateway->insert($data);
} else {
if ($this->getAlbum($id)) {
$this->tableGateway->update($data, array('id' => $id));
} else {
throw new \Exception('Form id does not exist');
}
}
}
public function deleteAlbum($id) {
$this->tableGateway->delete(array('id' => $id));
}
}
and the test:
class AlbumTableTest extends PHPUnit_Framework_TestCase {
public function testFetchAllReturnsAllAlbums() {
$resultSet = new ResultSet();
$mockTableGateway = $this->getMock('Zend\Db\TableGateway',
array('select'), array(), '', false);
$mockTableGateway->expects($this->once())
->method('select')
->with()
->will($this->returnValue($resultSet));
$albumTable = new AlbumTable($mockTableGateway);
$this->assertSame($resultSet, $albumTable->fechAll());
}
}
and the error:
Time: 102 ms, Memory: 5.00Mb
There was 1 error:
1) AlbumTest\Model\AlbumTableTest::testFetchAllReturnsAllAlbums
Argument 1 passed to Album\Model\AlbumTable::__construct() must be an instance of Zend\Db\TableGateway\TableGateway, instance of Mock_TableGateway_65b55cb0 given, called in C:\Users\MEEE\Google Drive\code\iis\www\CommunicationApp\module\Album\test\AlbumTest\Model\AlbumTableTest.php on line 20 and defined
C:\Users\MEEE\Google Drive\code\iis\www\CommunicationApp\module\Album\src\Album\Model\AlbumTable.php:9
C:\Users\MEEE\Google Drive\code\iis\www\CommunicationApp\module\Album\test\AlbumTest\Model\AlbumTableTest.php:20
FAILURES!
Tests: 4, Assertions: 9, Errors: 1.

Answer 1

You are not mocking the correct class. You are creating a mock of a Zend\Db\TableGateway and you need to actually mock Zend\Db\TableGateway\TableGateway
Change you test code to:
$mockTableGateway = $this->getMock('Zend\Db\TableGateway\TableGateway',
array('select'), array(), '', false);
Your mock was failing a type-hint because your not mocking the correct class.
Mock objects will extend the class that you are mocking, so they will be an instance of the class being mocked.