如何在调用请求之前更改Symfony5/PHPUnit中的区域设置？

我需要在功能测试中更改区域设置：

<?php

namespace App\Tests\Controller;

use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;

class TranslationControllerTest extends WebTestCase
{
    public function testIndex()
    {

        $client = static::createClient();

        $client->request('GET', '/translation.js');
        $client->getRequest()->setLocale('en');

        $content = $client->getResponse()->getContent();
        $trans = json_decode(substr($content, strpos($content, "'{") + 1, strpos($content, "}'") - strpos($content, "'{")), true);

        $this->assertEquals(200, $client->getResponse()->getStatusCode());
        $this->assertSame($trans['test.case'], 'en');

    }
}

---

我也已经搜索了很长时间了。我现在发现，它可以从以下方面推导：

我不确定这是否是定义的行为，因为在测试中更改两次区域设置的行为有点奇怪：

class MyTest extends WebTestCase
{
    public function testIndex()
    {
        $client = static::createClient();

        $session = self::$container->get(SessionInterface::class);
        $session->set('_locale', 'de');

        $client->request('GET', '/dashboard');
        // The resulting page is in English (my default locale)
        ....

        $session->set('_locale', 'nl');

        $client->request('GET', '/dashboard');
        // The resulting page is in German
        ....
    }
}

我一直在寻找这个也有相当一段时间。我现在发现，它可以从以下方面推导：

我不确定这是否是定义的行为，因为在测试中更改两次区域设置的行为有点奇怪：

class MyTest extends WebTestCase
{
    public function testIndex()
    {
        $client = static::createClient();

        $session = self::$container->get(SessionInterface::class);
        $session->set('_locale', 'de');

        $client->request('GET', '/dashboard');
        // The resulting page is in English (my default locale)
        ....

        $session->set('_locale', 'nl');

        $client->request('GET', '/dashboard');
        // The resulting page is in German
        ....
    }
}