From c6ed3c82e0cf1489a45fa4399d127df5ef43bc3b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A1lint=20Szekeres?= <szekeres@b4lint.hu>
Date: Thu, 17 Oct 2024 13:18:53 +0200
Subject: [PATCH] [Mime] fix encoding issue with UTF-8 addresses containing
 doubles spaces

---
 .../Component/Mime/Header/AbstractHeader.php       | 14 ++++++++++++++
 .../Mime/Tests/Header/MailboxHeaderTest.php        |  8 ++++++++
 2 files changed, 22 insertions(+)

diff --git a/src/Symfony/Component/Mime/Header/AbstractHeader.php b/src/Symfony/Component/Mime/Header/AbstractHeader.php
index d61df570bff73..2670367531e70 100644
--- a/src/Symfony/Component/Mime/Header/AbstractHeader.php
+++ b/src/Symfony/Component/Mime/Header/AbstractHeader.php
@@ -180,6 +180,20 @@ protected function getEncodableWordTokens(string $string): array
             $tokens[] = $encodedToken;
         }
 
+        foreach ($tokens as $i => $token) {
+            // whitespace(s) between 2 encoded tokens
+            if (
+                0 < $i
+                && isset($tokens[$i + 1])
+                && preg_match('~^[\t ]+$~', $token)
+                && $this->tokenNeedsEncoding($tokens[$i - 1])
+                && $this->tokenNeedsEncoding($tokens[$i + 1])
+            ) {
+                $tokens[$i - 1] .= $token.$tokens[$i + 1];
+                array_splice($tokens, $i, 2);
+            }
+        }
+
         return $tokens;
     }
 
diff --git a/src/Symfony/Component/Mime/Tests/Header/MailboxHeaderTest.php b/src/Symfony/Component/Mime/Tests/Header/MailboxHeaderTest.php
index 2fc8e1e881c27..bddadee0902db 100644
--- a/src/Symfony/Component/Mime/Tests/Header/MailboxHeaderTest.php
+++ b/src/Symfony/Component/Mime/Tests/Header/MailboxHeaderTest.php
@@ -62,6 +62,14 @@ public function testUtf8CharsInLocalPart()
     {
         $header = new MailboxHeader('Sender', new Address('fabïen@symfony.com'));
         $this->assertSame('fabïen@symfony.com', $header->getBodyAsString());
+
+        // name with single space
+        $header = new MailboxHeader('Sender', new Address('fabïen@symfony.com', 'Fabïen Pötencier'));
+        $this->assertSame('=?utf-8?Q?Fab=C3=AFen_P=C3=B6tencier?= <fabïen@symfony.com>', $header->getBodyAsString());
+
+        // name with double spaces
+        $header = new MailboxHeader('Sender', new Address('fabïen@symfony.com', 'Fabïen  Pötencier'));
+        $this->assertSame('=?utf-8?Q?Fab=C3=AFen__P=C3=B6tencier?= <fabïen@symfony.com>', $header->getBodyAsString());
     }
 
     public function testToString()