BarExtension example

$pass->process($container);

        $this->assertSame(['BAZ', 'FOO'], array_keys($container->getParameterBag()->getEnvPlaceholders()));
        $this->assertSame(['BAZ' => 1, 'FOO' => 0], $container->getEnvCounters());
    }

    public function testProcessedEnvsAreIncompatibleWithResolve()
    {
        $this->expectException(RuntimeException::class);
        $this->expectExceptionMessage('Using a cast in "env(int:FOO)" is incompatible with resolution at compile time in "Symfony\Component\DependencyInjection\Tests\Compiler\BarExtension". The logic in the extension should be moved to a compiler pass, or an env parameter with no cast should be used instead.');
        $container = new ContainerBuilder();
        $container->registerExtension(new BarExtension());
        $container->prependExtensionConfig('bar', []);

        (new MergeExtensionConfigurationPass())->process($container);
    }

    public function testThrowingExtensionsGetMergedBag()
    {
        $container = new ContainerBuilder();
        $container->registerExtension(new ThrowingExtension());
        $container->prependExtensionConfig('throwing', ['bar' => '%env(FOO)%']);