interface StrategyInterface {
  public function getClassName();
}

abstract class StrategyClass implements StrategyInterface {
  public function getClassName() {
    return get_class($this);
  }
}

abstract class StrategyDecorator implements StrategyInterface {

  private $decorated;

  public function __construct(StrategyClass $decorated) {
    $this->decorated = $decorated;
  }

  public function getClassName() {
    return $this->decorated->getClassName();
  }

}

/**
   * @dataProvider providerForTestGetStrategy
   * @param array $arguments
   * @param string $expected
   */
  public function testGetStrategy($arguments, $expected) {

    $this->assertEquals(
      __NAMESPACE__.'\'.$expected,
      $this->object->getStrategy($arguments)->getClassName()
    )
  }

//below there's another test to check if proper decorator is being used

class ProdObj
{
  ...
  protected:
     virtual bool checkCertainState();
};

class TestHelperProdObj : public ProdObj
{
  ...
  public:
     virtual bool checkCertainState() { return ProdObj::checkCertainState(); }
};