From aced44860bc8d96d26a0e8671f7aef39709db6fd Mon Sep 17 00:00:00 2001
From: Ralf Fritzsche <ralf.fritzsche@mll.com>
Date: Mon, 9 Nov 2026 15:45:41 +0100
Subject: [PATCH] feat: add StringUtil::removeZeroWidthCharacters
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Removes U+200B to U+200D and U+FEFF, which text pasted from mails or web
pages often carries and which charsets such as Mac Roman cannot encode.

🤖 Generated with Claude Code
---
 src/StringUtil.php       | 6 ++++++
 tests/StringUtilTest.php | 8 ++++++++
 2 files changed, 14 insertions(+)

diff --git a/src/StringUtil.php b/src/StringUtil.php
index 1f2c7e7..4dcdfe4 100644
--- a/src/StringUtil.php
+++ b/src/StringUtil.php
@@ -99,6 +99,12 @@ public static function normalizeLineEndings(string $input, string $to = self::WI
         return \Safe\preg_replace("/\r\n|\r|\n/", $to, $input);
     }
 
+    /** Removes U+200B to U+200D and U+FEFF, which text pasted from mails or web pages often carries. */
+    public static function removeZeroWidthCharacters(string $input): string
+    {
+        return \Safe\preg_replace('/[\x{200B}-\x{200D}\x{FEFF}]/u', '', $input);
+    }
+
     /** Convert string that could be in different UTF encodings (UTF-8, UTF-16BE, ...) to UTF-8. */
     public static function toUTF8(string $string): string
     {
diff --git a/tests/StringUtilTest.php b/tests/StringUtilTest.php
index d856567..442c7f3 100644
--- a/tests/StringUtilTest.php
+++ b/tests/StringUtilTest.php
@@ -89,6 +89,14 @@ public function testNormalizeLineEndings(): void
         );
     }
 
+    public function testRemoveZeroWidthCharacters(): void
+    {
+        self::assertSame(
+            'für dringende Anliegen',
+            StringUtil::removeZeroWidthCharacters("für drin\u{200B}gende\u{200C} An\u{200D}liegen\u{FEFF}")
+        );
+    }
+
     public function testUTF8(): void
     {
         $expectedUTF8 = 'test';