Improve mb_*trim polyfills

nicolas-grekas · nicolas-grekas · commit 8740a072b862 · 2024-06-20T10:18:00.000+02:00
diff --git a/Mbstring.php b/Mbstring.php
@@ -79,16 +79,14 @@ final class Mbstring
         ['μ', 's', 'ι',        'σ', 'β',        'θ',        'φ',        'π',        'κ',        'ρ',        'ε',        "\xE1\xB9\xA1", 'ι'],
     ];
 
-    private const CHARACTERS = " \f\n\r\t\v\x00\u{00A0}\u{1680}\u{2000}\u{2001}\u{2002}\u{2003}\u{2004}\u{2005}\u{2006}\u{2007}\u{2008}\u{2009}\u{200A}\u{2028}\u{2029}\u{202F}\u{205F}\u{3000}\u{0085}\u{180E}";
-
     private static $encodingList = ['ASCII', 'UTF-8'];
     private static $language = 'neutral';
     private static $internalEncoding = 'UTF-8';
 
     public static function mb_convert_encoding($s, $toEncoding, $fromEncoding = null)
     {
         if (\is_array($s)) {
-            if (PHP_VERSION_ID < 70200) {
+            if (\PHP_VERSION_ID < 70200) {
                 trigger_error('mb_convert_encoding() expects parameter 1 to be string, array given', \E_USER_WARNING);
 
                 return null;
@@ -987,68 +985,73 @@ private static function getEncoding($encoding)
 
     public static function mb_trim(string $string, ?string $characters = null, ?string $encoding = null): string
     {
-        return self::mb_internal_trim('^[%s]+|[%s]+$', $string, $characters, $encoding);
+        return self::mb_internal_trim('{^[%s]+|[%1$s]+$}Du', $string, $characters, $encoding, __FUNCTION__);
     }
 
     public static function mb_ltrim(string $string, ?string $characters = null, ?string $encoding = null): string
     {
-        return self::mb_internal_trim('^[%s]+', $string, $characters, $encoding);
+        return self::mb_internal_trim('{^[%s]+}Du', $string, $characters, $encoding, __FUNCTION__);
     }
 
     public static function mb_rtrim(string $string, ?string $characters = null, ?string $encoding = null): string
     {
-        return self::mb_internal_trim('[%s]+$', $string, $characters, $encoding);
+        return self::mb_internal_trim('{[%s]+$}D', $string, $characters, $encoding, __FUNCTION__);
     }
 
-    private static function mb_internal_trim(string $regex, string $string, ?string $characters = null, ?string $encoding = null): string
+    private static function mb_internal_trim(string $regex, string $string, ?string $characters, ?string $encoding, string $function): string
     {
         if (null === $encoding) {
-            $encoding = mb_internal_encoding();
+            $encoding = self::mb_internal_encoding();
+        } else {
+            self::assertEncoding($encoding, $function.'(): Argument #3 ($encoding) must be a valid encoding, "%s" given');
         }
 
-        self::assertEncoding($encoding, debug_backtrace()[1]['function'].'(): Argument #3 ($encoding) must be a valid encoding, "%s" given.');
-
         if ('' === $characters) {
-            return null === $encoding ? $string : mb_convert_encoding($string, $encoding);
+            return null === $encoding ? $string : self::mb_convert_encoding($string, $encoding);
         }
 
-        if (null === $characters) {
-            $characters = self::CHARACTERS;
-        }
+        if ('UTF-8' === $encoding) {
+            $encoding = null;
+            if (!preg_match('//u', $string)) {
+                $string = @iconv('UTF-8', 'UTF-8//IGNORE', $string);
+            }
+            if (null !== $characters && !preg_match('//u', $characters)) {
+                $characters = @iconv('UTF-8', 'UTF-8//IGNORE', $characters);
+            }
+        } else {
+            $string = iconv($encoding, 'UTF-8//IGNORE', $string);
 
-        $regexCharacter = preg_quote($characters ?? '', '/');
-        $regex = sprintf($regex, $regexCharacter, $regexCharacter);
+            if (null !== $characters) {
+                $characters = iconv($encoding, 'UTF-8//IGNORE', $characters);
+            }
+        }
 
-        if ('ASCII' === mb_detect_encoding($characters) && 'ASCII' === mb_detect_encoding($string) && !empty(array_intersect(str_split(self::CHARACTERS), str_split($string)))) {
-            $options = 'g';
+        if (null === $characters) {
+            $characters = "\\0 \f\n\r\t\v\u{00A0}\u{1680}\u{2000}\u{2001}\u{2002}\u{2003}\u{2004}\u{2005}\u{2006}\u{2007}\u{2008}\u{2009}\u{200A}\u{2028}\u{2029}\u{202F}\u{205F}\u{3000}\u{0085}\u{180E}";
         } else {
-            $options = '';
+            $characters = preg_quote($characters);
         }
-        
-        try {
-            $test = mb_ereg_replace($regex, "", $string, $options);
 
-            if (null === $test) {
-                throw new \Exception();
-            }
+        $string = preg_replace(sprintf($regex, $characters), '', $string);
 
-            return $test;
-        } catch (\Exception $e) {
-            return preg_replace('/'.$regex.'/', "", $string);
+        if (null === $encoding) {
+            return $string;
         }
-    } 
+
+        return iconv('UTF-8', $encoding.'//IGNORE', $string);
+    }
 
     private static function assertEncoding(string $encoding, string $errorFormat): void
     {
         try {
             $validEncoding = @self::mb_check_encoding('', $encoding);
         } catch (\ValueError $e) {
-            throw new \ValueError(\sprintf($errorFormat, $encoding));
+            throw new \ValueError(sprintf($errorFormat, $encoding));
         }
 
         // BC for PHP 7.3 and lower
         if (!$validEncoding) {
-            throw new \ValueError(\sprintf($errorFormat, $encoding));
+            throw new \ValueError(sprintf($errorFormat, $encoding));
         }
     }
 }
