Convenient PHPUnit mocking of Singleton Classes

sample_class.php

<?php

class Sample {

   public __construct() {
   }

   public function sayHello($name) {
      return Someclass::getInstance()->hello($name);
   }

}

sample_test.php

<?php

class SampleTest extends \PHPUnit_Framework_TestCase {

   public function testSayHello() {
      $sample = new Sample();
      $name = 'Chris';
      $replace = 'Goodbye, Chris!';
      SomeclassMock::expects($name, $replace);
      $this->assertEquals("Goodbye, Chris!", $sample->sayHello($name));
      SomeclassMock::cleanup();
   }

}

singleton.php

<?php

class Someclass {

   protected static $self;

   protected __construct() {
   }

   public static function getInstance() {
      if (empty(static::$self)) {
         static::$self = new Someclass();
      }
      return static::$self;
   }

   public function hello($name) {
      return "hello, $name!";
   }

}

someclass_mock.php

<?php

class SomeclassMock {

	/**
	 * Generates a mock object on the singleton Someclass util object.
	 *
	 * @param array $name
	 * @return void
	 */
	public static function expects($name, $replace) {
		// Mock the object
		$mock = \PHPUnit_Framework_MockObject_Generator::getMock(
			'Someclass',
			array('hello'),
			array(),
			'',
			false
		);

		// Replace protected self reference with mock object
		$ref = new \ReflectionProperty('Someclass', 'self');
		$ref->setAccessible(true);
		$ref->setValue(null, $mock);

		// Set expectations and return values
		$mock
			->expects(new \PHPUnit_Framework_MockObject_Matcher_InvokedCount(1))
			->method('hello')
			->with(
				\PHPUnit_Framework_Assert::equalTo($name)
			)
			->will(new \PHPUnit_Framework_MockObject_Stub_Return($replace));
	}

	public static function cleanup() {
		$ref = new \ReflectionProperty('Someclass', 'self');
		$ref->setAccessible(true);
		$ref->setValue(null, null);
	}

}