diff --git a/src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php b/src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php
index c0e9e5c03b..81a2da7298 100644
--- a/src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php
@@ -326,7 +326,7 @@ class ReflectionCaster
                         if (!$param->isOptional() && $param->allowsNull()) {
                             $signature .= '?';
                         }
-                        $signature .= substr(strrchr('\\'.$type->getName(), '\\'), 1);
+                        $signature .= substr(strrchr('\\'.$type->getName(), '\\'), 1).' ';
                     }
                 }
                 $signature .= $k;