symfony · nicolas-grekas · Sep 20, 2023 · Jul 31, 2023
diff --git a/src/Symfony/Component/DependencyInjection/Container.php b/src/Symfony/Component/DependencyInjection/Container.php
@@ -391,13 +391,9 @@ protected function getEnv(string $name)
             $localName = $name;
         }
 
-        if ($processors->has($prefix)) {
-            $processor = $processors->get($prefix);
-        } else {
-            $processor = new EnvVarProcessor($this);
-            if (false === $i) {
-                $prefix = '';
-            }
+        $processor = $processors->has($prefix) ? $processors->get($prefix) : new EnvVarProcessor($this);
+        if (false === $i) {
+            $prefix = '';
         }
 
         $this->resolving[$envName] = true;

diff --git a/src/Symfony/Component/DependencyInjection/EnvVarProcessorInterface.php b/src/Symfony/Component/DependencyInjection/EnvVarProcessorInterface.php
@@ -23,7 +23,7 @@ interface EnvVarProcessorInterface
     /**
      * Returns the value of the given variable as managed by the current instance.
      *
-     * @param string   $prefix The namespace of the variable
+     * @param string   $prefix The namespace of the variable; when the empty string is passed, null values should be kept as is
      * @param string   $name   The name of the variable within the namespace
      * @param \Closure $getEnv A closure that allows fetching more env vars
      *

diff --git a/src/Symfony/Component/DependencyInjection/Tests/ContainerTest.php b/src/Symfony/Component/DependencyInjection/Tests/ContainerTest.php
@@ -14,11 +14,13 @@
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\DependencyInjection\Container;
 use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\DependencyInjection\EnvVarProcessor;
 use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
 use Symfony\Component\DependencyInjection\Exception\ServiceCircularReferenceException;
 use Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException;
 use Symfony\Component\DependencyInjection\ParameterBag\FrozenParameterBag;
 use Symfony\Component\DependencyInjection\ParameterBag\ParameterBag;
+use Symfony\Component\DependencyInjection\ServiceLocator;
 use Symfony\Contracts\Service\ResetInterface;
 
 class ContainerTest extends TestCase
@@ -405,6 +407,33 @@ public function testRequestAnInternalSharedPrivateService()
         $c->get('internal_dependency');
         $c->get('internal');
     }
+
+    public function testGetEnvDoesNotAutoCastNullWithDefaultEnvVarProcessor()
+    {
+        $container = new Container();
+        $container->setParameter('env(FOO)', null);
+        $container->compile();
+
+        $r = new \ReflectionMethod($container, 'getEnv');
+        $r->setAccessible(true);
+        $this->assertNull($r->invoke($container, 'FOO'));
+    }
+
+    public function testGetEnvDoesNotAutoCastNullWithEnvVarProcessorsLocatorReturningDefaultEnvVarProcessor()
+    {
+        $container = new Container();
+        $container->setParameter('env(FOO)', null);
+        $container->set('container.env_var_processors_locator', new ServiceLocator([
+            'string' => static function () use ($container): EnvVarProcessor {
+                return new EnvVarProcessor($container);
+            },
+        ]));
+        $container->compile();
+
+        $r = new \ReflectionMethod($container, 'getEnv');
+        $r->setAccessible(true);
+        $this->assertNull($r->invoke($container, 'FOO'));
+    }
 }
 
 class ProjectServiceContainer extends Container