From 66ca61112dfae3ca5b10bdcadd0ab6d934f06d74 Mon Sep 17 00:00:00 2001
From: dsech <dsech@users.noreply.github.com>
Date: Mon, 18 Oct 2021 17:36:15 +0300
Subject: [PATCH] [Messenger] fix: TypeError in PhpSerializer::encode()

Ensure a MessageDecodingFailedException is thrown when the string to be unserialized is an empty string.

This happens because unserializing an empty string does not issue a PHP warning, and simply returns false.
---
 .../Transport/Serialization/PhpSerializerTest.php    | 12 ++++++++++++
 .../Transport/Serialization/PhpSerializer.php        |  4 ++++
 2 files changed, 16 insertions(+)

diff --git a/src/Symfony/Component/Messenger/Tests/Transport/Serialization/PhpSerializerTest.php b/src/Symfony/Component/Messenger/Tests/Transport/Serialization/PhpSerializerTest.php
index 96f4503c2eede..891683790ad47 100644
--- a/src/Symfony/Component/Messenger/Tests/Transport/Serialization/PhpSerializerTest.php
+++ b/src/Symfony/Component/Messenger/Tests/Transport/Serialization/PhpSerializerTest.php
@@ -53,6 +53,18 @@ public function testDecodingFailsWithBadFormat()
         ]);
     }
 
+    public function testDecodingFailsWithBadBase64Body()
+    {
+        $this->expectException(MessageDecodingFailedException::class);
+        $this->expectExceptionMessageMatches('/Could not decode/');
+
+        $serializer = new PhpSerializer();
+
+        $serializer->decode([
+            'body' => 'x',
+        ]);
+    }
+
     public function testDecodingFailsWithBadClass()
     {
         $this->expectException(MessageDecodingFailedException::class);
diff --git a/src/Symfony/Component/Messenger/Transport/Serialization/PhpSerializer.php b/src/Symfony/Component/Messenger/Transport/Serialization/PhpSerializer.php
index 3a4804903c673..0516ee2f40292 100644
--- a/src/Symfony/Component/Messenger/Transport/Serialization/PhpSerializer.php
+++ b/src/Symfony/Component/Messenger/Transport/Serialization/PhpSerializer.php
@@ -58,6 +58,10 @@ public function encode(Envelope $envelope): array
 
     private function safelyUnserialize(string $contents)
     {
+        if ('' === $contents) {
+            throw new MessageDecodingFailedException('Could not decode an empty message using PHP serialization.');
+        }
+
         $signalingException = new MessageDecodingFailedException(sprintf('Could not decode message using PHP serialization: %s.', $contents));
         $prevUnserializeHandler = ini_set('unserialize_callback_func', self::class.'::handleUnserializeCallback');
         $prevErrorHandler = set_error_handler(function ($type, $msg, $file, $line, $context = []) use (&$prevErrorHandler, $signalingException) {