[Translation] Handle the translation of empty strings

Author: javiereguiluz

Extension/TranslationExtension.php

@@ -116,6 +116,10 @@ public function trans($message, $arguments = [], string $domain = null, string $
                 throw new \TypeError(sprintf('Argument 2 passed to "%s()" must be a locale passed as a string when the message is a "%s", "%s" given.', __METHOD__, TranslatableInterface::class, get_debug_type($arguments)));
             }
 
+            if ($message instanceof TranslatableMessage && '' === $message->getMessage()) {
+                return '';
+            }
+
             return $message->trans($this->getTranslator(), $locale ?? (\is_string($arguments) ? $arguments : null));
         }
 

Tests/Extension/TranslationExtensionTest.php

@@ -124,6 +124,7 @@ public function getTransTests()
             ['{{ foo|trans }}', '', ['foo' => null]],
 
             // trans object
+            ['{{ t("")|trans }}', ''],
             ['{{ t("Hello")|trans }}', 'Hello'],
             ['{{ t(name)|trans }}', 'Symfony', ['name' => 'Symfony']],
             ['{{ t(hello, { \'%name%\': \'Symfony\' })|trans }}', 'Hello Symfony', ['hello' => 'Hello %name%']],