LocaleAwareListener example

class LocaleAwareListenerTest extends TestCase
{
    private LocaleAwareListener $listener;
    private MockObject&LocaleAwareInterface $localeAwareService;
    private RequestStack $requestStack;

    protected function setUp(): void
    {
        $this->localeAwareService = $this->createMock(LocaleAwareInterface::class);
        $this->requestStack = new RequestStack();
        $this->listener = new LocaleAwareListener(new \ArrayIterator([$this->localeAwareService]), $this->requestStack);
    }

    public function testLocaleIsSetInOnKernelRequest()
    {
        $this->localeAwareService
            ->expects($this->once())
            ->method('setLocale')
            ->with($this->equalTo('fr'));

        $event = new RequestEvent($this->createMock(HttpKernelInterface::class), $this->createRequest('fr'), HttpKernelInterface::MAIN_REQUEST);
        $this->listener->onKernelRequest($event);
    }