diff --git a/src/Compiler.php b/src/Compiler.php
index 81e0f7e7..fa97f684 100644
--- a/src/Compiler.php
+++ b/src/Compiler.php
@@ -12,6 +12,7 @@
 use Symfony\Component\DependencyInjection\Dumper\PhpDumper;
 use Symfony\Component\Filesystem\Filesystem;
 
+use function array_is_list;
 use function array_pop;
 use function assert;
 use function dirname;
@@ -86,8 +87,9 @@ private function getContainerContent(
         $options['inline_class_loader'] = $options['inline_factories'];
 
         $content = (new PhpDumper($container))->dump($options);
-        assert(is_array($content));
+        assert(is_array($content) && ! array_is_list($content));
 
+        // @phpstan-ignore return.type
         return $content;
     }