Symfony\Component\DependencyInjection\ContainerBuilder::getCompiler PHP Method

    public function getCompiler()
    {
        if (null === $this->compiler) {
            $this->compiler = new Compiler();
        }

        return $this->compiler;
    }

 private function then_compiler_passes_are_added()
 {
     $passes = $this->container->getCompiler()->getPassConfig()->getBeforeOptimizationPasses();
     $classes = array_map(function ($pass) {
         return get_class($pass);
     }, $passes);
     $expectedPassClasses = array('Devhelp\\PiwikBundle\\DependencyInjection\\Compiler\\AddPiwikClientDefinition', 'Devhelp\\PiwikBundle\\DependencyInjection\\Compiler\\InsertParamsServices');
     $this->assertEquals($expectedPassClasses, $classes);
 }