Using PHPUnit 3.5 MockBuilder to create a mock concrete object of an abstract class

gistfile1.php

<?php
//Create mock BaseCredential called 'MockAdminCredential' whose 'calculate' 
//function will always return true. All other methods will return NULL
//as per the default behavior of a stub.
$this->mockAdminCredential = $this->getMockBuilder('BaseCredential')
    ->setMockClassName('MockAdminCredential')
    ->setMethods(array('calculate'))
    ->getMock()
    ->expects($this->any())
    ->method('calculate')
    ->will($this->returnValue(true));