[Translator] DataCollector always shows default instead of current locale

[althaus]

Symfony version(s) affected: 4.3.0-BETA2

Description

The current BETA2 has an issue with the TranslationDataCollector in combination with the LocaleAwareListener. I'm running a page with _locale prefixed routes and all works fine, but the profiler shows an incorrect locale. It just shows my default en.

For me the LocaleAwareListener is to blame for this. It's subscribing to onKernelRequest and onKernelFinishRequest and therefore setting the locale twice.

The first time all wents fine, but on the finish part

    public function onKernelFinishRequest(FinishRequestEvent $event): void
    {
        if (null === $parentRequest = $this->requestStack->getParentRequest()) {
            $this->setLocale($event->getRequest()->getDefaultLocale());

            return;
        }

        $this->setLocale($parentRequest->getLocale(), $parentRequest->getDefaultLocale());
    }

we don't have a $parentRequest and setLocale() is called with the default value, which is then injected into the Translator and lately collected by the TranslationDataCollector.

How to reproduce

Setup a simple app with 2 locales and check the profiler.

Possible Solution

No clue what part is the broken one. Could also be the collector running too late.

Additional context

See attached screenshots. Locale shows "en" while it's using German messages. The intl part is also set correctly.

Cheers
Matthias