symfony
diff --git a/‎src/Symfony/Bridge/Twig/Mime/BodyRenderer.php
Copy file name to clipboardExpand all lines: src/Symfony/Bridge/Twig/Mime/BodyRenderer.php
+18-1Lines changed: 18 additions & 1 deletion b/‎src/Symfony/Bridge/Twig/Mime/BodyRenderer.php
Copy file name to clipboardExpand all lines: src/Symfony/Bridge/Twig/Mime/BodyRenderer.php
+18-1Lines changed: 18 additions & 1 deletion
diff --git a/‎src/Symfony/Bridge/Twig/Tests/Mime/BodyRendererTest.php
Copy file name to clipboardExpand all lines: src/Symfony/Bridge/Twig/Tests/Mime/BodyRendererTest.php
+21Lines changed: 21 additions & 0 deletions b/‎src/Symfony/Bridge/Twig/Tests/Mime/BodyRendererTest.php
Copy file name to clipboardExpand all lines: src/Symfony/Bridge/Twig/Tests/Mime/BodyRendererTest.php
+21Lines changed: 21 additions & 0 deletions
@@ -49,7 +49,7 @@ public function render(Message $message): void
 
         $previousRenderingKey = $messageContext[__CLASS__] ?? null;
         unset($messageContext[__CLASS__]);
-        $currentRenderingKey = md5(serialize([$messageContext, $message->getTextTemplate(), $message->getHtmlTemplate()]));
+        $currentRenderingKey = $this->getFingerPrint($message);
         if ($previousRenderingKey === $currentRenderingKey) {
             return;
         }
@@ -77,6 +77,23 @@ public function render(Message $message): void
         $message->context($message->getContext() + [__CLASS__ => $currentRenderingKey]);
     }
 
+    private function getFingerPrint(TemplatedEmail $message): string
+    {
+        $messageContext = $message->getContext();
+        unset($messageContext[__CLASS__]);
+
+        $payload = [$messageContext, $message->getTextTemplate(), $message->getHtmlTemplate()];
+        try {
+            $serialized = serialize($payload);
+        } catch (\Exception $e) {
+            // Serialization of 'Closure' is not allowed
+            // Happens when context contain a closure, in that case, we assume that context always change.
+            $serialized = random_bytes(8);
+        }
+
+        return md5($serialized);
+    }
+
     private function convertHtmlToText(string $html): string
     {
         if (null !== $this->converter) {
 
@@ -100,6 +100,27 @@ public function testRenderedOnce()
         $this->assertEquals('reset', $email->getTextBody());
     }
 
+    public function testRenderedOnceUnserializableContext()
+    {
+        $twig = new Environment(new ArrayLoader([
+            'text' => 'Text',
+        ]));
+        $renderer = new BodyRenderer($twig);
+        $email = (new TemplatedEmail())
+            ->to('fabien@symfony.com')
+            ->from('helene@symfony.com')
+        ;
+        $email->textTemplate('text');
+        $email->context([
+            'foo' => static function () {
+                return 'bar';
+            },
+        ]);
+
+        $renderer->render($email);
+        $this->assertEquals('Text', $email->getTextBody());
+    }
+
     private function prepareEmail(?string $text, ?string $html, array $context = []): TemplatedEmail
     {
         $twig = new Environment(new ArrayLoader([