2.3.2

Fix #134: Improve support without mbstring

CHANGELOG.md

@@ -1,4 +1,12 @@
-### 2.3.0 (2015-03-19)
+### 2.3.2 (2016-05-02)
+
+* Improve support without mbstring
+
+### 2.3.1 (2016-03-21)
+
+* Always use root namespace for mbstring functions
+
+### 2.3.0 (2016-03-19)
 
 * Add Persian characters in Stringy::charsArray()
 * Use symfony/polyfill-mbstring to avoid dependency on ext-mbstring

README.md

@@ -239,9 +239,9 @@ integer, boolean, etc.
 ```php
 use Stringy\StaticStringy as S;
 
-// Translates to Stringy::create('fòôbàř', 'UTF-8')->slice(0, 3);
+// Translates to Stringy::create('fòôbàř')->slice(0, 3);
 // Returns a Stringy object with the string "fòô"
-S::slice('fòôbàř', 0, 3, 'UTF-8');
+S::slice('fòôbàř', 0, 3);
 ```
 
 ## Class methods
@@ -255,7 +255,7 @@ then returns the initialized object. Throws an InvalidArgumentException
 if the first argument is an array or object without a __toString method.
 
 ```php
-$stringy = S::create('fòôbàř', 'UTF-8'); // 'fòôbàř'
+$stringy = S::create('fòôbàř'); // 'fòôbàř'
 ```
 
 ## Instance Methods
@@ -420,7 +420,7 @@ s('fòôbàř')->first(3); // 'fòô'
 Returns the encoding used by the Stringy object.
 
 ```php
-s('fòôbàř', 'UTF-8')->getEncoding(); // 'UTF-8'
+s('fòôbàř')->getEncoding(); // 'UTF-8'
 ```
 
 ##### hasLowerCase()
@@ -686,7 +686,8 @@ to a lack of support in the bundled version of Oniguruma in PHP < 5.6,
 and current versions of HHVM (3.8 and below).
 
 ```php
-s('fòô ')->regexReplace('f[òô]+\s', 'bàř', 'msr'); // 'bàř'
+s('fòô ')->regexReplace('f[òô]+\s', 'bàř'); // 'bàř'
+s('fò')->regexReplace('(ò)', '\\1ô'); // 'fòô'
 ```
 
 ##### removeLeft(string $substring)

src/Stringy.php

@@ -52,7 +52,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         }
 
         $this->str = (string) $str;
-        $this->encoding = $encoding ?: mb_internal_encoding();
+        $this->encoding = $encoding ?: \mb_internal_encoding();
     }
 
     /**
@@ -122,7 +122,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
             return static::create('', $this->encoding);
         }
 
-        $substrIndex = $startIndex + mb_strlen($start, $this->encoding);
+        $substrIndex = $startIndex + \mb_strlen($start, $this->encoding);
         $endIndex = $this->indexOf($end, $substrIndex);
         if ($endIndex === false) {
             return static::create('', $this->encoding);
@@ -148,7 +148,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
             '/[-_\s]+(.)?/u',
             function ($match) use ($encoding) {
                 if (isset($match[1])) {
-                    return mb_strtoupper($match[1], $encoding);
+                    return \mb_strtoupper($match[1], $encoding);
                 }
 
                 return '';
@@ -159,7 +159,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         $stringy->str = preg_replace_callback(
             '/[\d]+(.)?/u',
             function ($match) use ($encoding) {
-                return mb_strtoupper($match[0], $encoding);
+                return \mb_strtoupper($match[0], $encoding);
             },
             $stringy->str
         );
@@ -208,10 +208,10 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         $encoding = $this->encoding;
 
         if ($caseSensitive) {
-            return (mb_strpos($this->str, $needle, 0, $encoding) !== false);
+            return (\mb_strpos($this->str, $needle, 0, $encoding) !== false);
         }
 
-        return (mb_stripos($this->str, $needle, 0, $encoding) !== false);
+        return (\mb_stripos($this->str, $needle, 0, $encoding) !== false);
     }
 
     /**
@@ -284,13 +284,13 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
     public function countSubstr($substring, $caseSensitive = true)
     {
         if ($caseSensitive) {
-            return mb_substr_count($this->str, $substring, $this->encoding);
+            return \mb_substr_count($this->str, $substring, $this->encoding);
         }
 
-        $str = mb_strtoupper($this->str, $this->encoding);
+        $str = \mb_strtoupper($this->str, $this->encoding);
-        $substring = mb_strtoupper($substring, $this->encoding);
+        $substring = \mb_strtoupper($substring, $this->encoding);
 
-        return mb_substr_count($str, $substring, $this->encoding);
+        return \mb_substr_count($str, $substring, $this->encoding);
     }
 
     /**
@@ -316,15 +316,14 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function delimit($delimiter)
     {
-        // Save current regex encoding so we can reset it after
+        $regexEncoding = $this->regexEncoding();
-        $regexEncoding = mb_regex_encoding();
+        $this->regexEncoding($this->encoding);
-        mb_regex_encoding($this->encoding);
 
-        $str = mb_ereg_replace('\B([A-Z])', '-\1', $this->trim());
+        $str = $this->eregReplace('\B([A-Z])', '-\1', $this->trim());
-        $str = mb_strtolower($str, $this->encoding);
+        $str = \mb_strtolower($str, $this->encoding);
-        $str = mb_ereg_replace('[-_\s]+', $delimiter, $str);
+        $str = $this->eregReplace('[-_\s]+', $delimiter, $str);
 
-        mb_regex_encoding($regexEncoding);
+        $this->regexEncoding($regexEncoding);
 
         return static::create($str, $this->encoding);
     }
@@ -340,15 +339,15 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function endsWith($substring, $caseSensitive = true)
     {
-        $substringLength = mb_strlen($substring, $this->encoding);
+        $substringLength = \mb_strlen($substring, $this->encoding);
         $strLength = $this->length();
 
-        $endOfStr = mb_substr($this->str, $strLength - $substringLength,
+        $endOfStr = \mb_substr($this->str, $strLength - $substringLength,
             $substringLength, $this->encoding);
 
         if (!$caseSensitive) {
-            $substring = mb_strtolower($substring, $this->encoding);
+            $substring = \mb_strtolower($substring, $this->encoding);
-            $endOfStr = mb_strtolower($endOfStr, $this->encoding);
+            $endOfStr = \mb_strtolower($endOfStr, $this->encoding);
         }
 
         return (string) $substring === $endOfStr;
@@ -508,7 +507,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function indexOf($needle, $offset = 0)
     {
-        return mb_strpos($this->str, (string) $needle,
+        return \mb_strpos($this->str, (string) $needle,
             (int) $offset, $this->encoding);
     }
 
@@ -524,7 +523,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function indexOfLast($needle, $offset = 0)
     {
-        return mb_strrpos($this->str, (string) $needle,
+        return \mb_strrpos($this->str, (string) $needle,
             (int) $offset, $this->encoding);
     }
 
@@ -542,8 +541,8 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
             return $stringy;
         }
 
-        $start = mb_substr($stringy->str, 0, $index, $stringy->encoding);
+        $start = \mb_substr($stringy->str, 0, $index, $stringy->encoding);
-        $end = mb_substr($stringy->str, $index, $stringy->length(),
+        $end = \mb_substr($stringy->str, $index, $stringy->length(),
             $stringy->encoding);
 
         $stringy->str = $start . $substring . $end;
@@ -681,7 +680,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function length()
     {
-        return mb_strlen($this->str, $this->encoding);
+        return \mb_strlen($this->str, $this->encoding);
     }
 
     /**
@@ -692,7 +691,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function lines()
     {
-        $array = mb_split('[\r\n]{1,2}', $this->str);
+        $array = $this->split('[\r\n]{1,2}', $this->str);
         for ($i = 0; $i < count($array); $i++) {
             $array[$i] = static::create($array[$i], $this->encoding);
         }
@@ -709,13 +708,13 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
     public function longestCommonPrefix($otherStr)
     {
         $encoding = $this->encoding;
-        $maxLength = min($this->length(), mb_strlen($otherStr, $encoding));
+        $maxLength = min($this->length(), \mb_strlen($otherStr, $encoding));
 
         $longestCommonPrefix = '';
         for ($i = 0; $i < $maxLength; $i++) {
-            $char = mb_substr($this->str, $i, 1, $encoding);
+            $char = \mb_substr($this->str, $i, 1, $encoding);
 
-            if ($char == mb_substr($otherStr, $i, 1, $encoding)) {
+            if ($char == \mb_substr($otherStr, $i, 1, $encoding)) {
                 $longestCommonPrefix .= $char;
             } else {
                 break;
@@ -734,13 +733,13 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
     public function longestCommonSuffix($otherStr)
     {
         $encoding = $this->encoding;
-        $maxLength = min($this->length(), mb_strlen($otherStr, $encoding));
+        $maxLength = min($this->length(), \mb_strlen($otherStr, $encoding));
 
         $longestCommonSuffix = '';
         for ($i = 1; $i <= $maxLength; $i++) {
-            $char = mb_substr($this->str, -$i, 1, $encoding);
+            $char = \mb_substr($this->str, -$i, 1, $encoding);
 
-            if ($char == mb_substr($otherStr, -$i, 1, $encoding)) {
+            if ($char == \mb_substr($otherStr, -$i, 1, $encoding)) {
                 $longestCommonSuffix = $char . $longestCommonSuffix;
             } else {
                 break;
@@ -764,7 +763,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         $encoding = $this->encoding;
         $stringy = static::create($this->str, $encoding);
         $strLength = $stringy->length();
-        $otherLength = mb_strlen($otherStr, $encoding);
+        $otherLength = \mb_strlen($otherStr, $encoding);
 
         // Return if either string is empty
         if ($strLength == 0 || $otherLength == 0) {
@@ -779,8 +778,8 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
 
         for ($i = 1; $i <= $strLength; $i++) {
             for ($j = 1; $j <= $otherLength; $j++) {
-                $strChar = mb_substr($stringy->str, $i - 1, 1, $encoding);
+                $strChar = \mb_substr($stringy->str, $i - 1, 1, $encoding);
-                $otherChar = mb_substr($otherStr, $j - 1, 1, $encoding);
+                $otherChar = \mb_substr($otherStr, $j - 1, 1, $encoding);
 
                 if ($strChar == $otherChar) {
                     $table[$i][$j] = $table[$i - 1][$j - 1] + 1;
@@ -794,7 +793,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
             }
         }
 
-        $stringy->str = mb_substr($stringy->str, $end - $len, $len, $encoding);
+        $stringy->str = \mb_substr($stringy->str, $end - $len, $len, $encoding);
 
         return $stringy;
     }
@@ -806,11 +805,11 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function lowerCaseFirst()
     {
-        $first = mb_substr($this->str, 0, 1, $this->encoding);
+        $first = \mb_substr($this->str, 0, 1, $this->encoding);
-        $rest = mb_substr($this->str, 1, $this->length() - 1,
+        $rest = \mb_substr($this->str, 1, $this->length() - 1,
             $this->encoding);
 
-        $str = mb_strtolower($first, $this->encoding) . $rest;
+        $str = \mb_strtolower($first, $this->encoding) . $rest;
 
         return static::create($str, $this->encoding);
     }
@@ -855,7 +854,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
             throw new OutOfBoundsException('No character exists at the index');
         }
 
-        return mb_substr($this->str, $offset, 1, $this->encoding);
+        return \mb_substr($this->str, $offset, 1, $this->encoding);
     }
 
     /**
@@ -983,11 +982,11 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function regexReplace($pattern, $replacement, $options = 'msr')
     {
-        $regexEncoding = mb_regex_encoding();
+        $regexEncoding = $this->regexEncoding();
-        mb_regex_encoding($this->encoding);
+        $this->regexEncoding($this->encoding);
 
-        $str = mb_ereg_replace($pattern, $replacement, $this->str, $options);
+        $str = $this->eregReplace($pattern, $replacement, $this->str, $options);
-        mb_regex_encoding($regexEncoding);
+        $this->regexEncoding($regexEncoding);
 
         return static::create($str, $this->encoding);
     }
@@ -1003,7 +1002,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         $stringy = static::create($this->str, $this->encoding);
 
         if ($stringy->startsWith($substring)) {
-            $substringLength = mb_strlen($substring, $stringy->encoding);
+            $substringLength = \mb_strlen($substring, $stringy->encoding);
             return $stringy->substr($substringLength);
         }
 
@@ -1021,7 +1020,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         $stringy = static::create($this->str, $this->encoding);
 
         if ($stringy->endsWith($substring)) {
-            $substringLength = mb_strlen($substring, $stringy->encoding);
+            $substringLength = \mb_strlen($substring, $stringy->encoding);
             return $stringy->substr(0, $stringy->length() - $substringLength);
         }
 
@@ -1065,7 +1064,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
 
         // Loop from last index of string to first
         for ($i = $strLength - 1; $i >= 0; $i--) {
-            $reversed .= mb_substr($this->str, $i, 1, $this->encoding);
+            $reversed .= \mb_substr($this->str, $i, 1, $this->encoding);
         }
 
         return static::create($reversed, $this->encoding);
@@ -1090,16 +1089,16 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
 
         // Need to further trim the string so we can append the substring
         $encoding = $stringy->encoding;
-        $substringLength = mb_strlen($substring, $encoding);
+        $substringLength = \mb_strlen($substring, $encoding);
         $length = $length - $substringLength;
 
-        $truncated = mb_substr($stringy->str, 0, $length, $encoding);
+        $truncated = \mb_substr($stringy->str, 0, $length, $encoding);
 
         // If the last word was truncated
         if (mb_strpos($stringy->str, ' ', $length - 1, $encoding) != $length) {
             // Find pos of the last occurrence of a space, get up to that
-            $lastPos = mb_strrpos($truncated, ' ', 0, $encoding);
+            $lastPos = \mb_strrpos($truncated, ' ', 0, $encoding);
-            $truncated = mb_substr($truncated, 0, $lastPos, $encoding);
+            $truncated = \mb_substr($truncated, 0, $lastPos, $encoding);
         }
 
         $stringy->str = $truncated . $substring;
@@ -1120,7 +1119,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
 
         $shuffledStr = '';
         foreach ($indexes as $i) {
-            $shuffledStr .= mb_substr($this->str, $i, 1, $this->encoding);
+            $shuffledStr .= \mb_substr($this->str, $i, 1, $this->encoding);
         }
 
         return static::create($shuffledStr, $this->encoding);
@@ -1159,13 +1158,13 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function startsWith($substring, $caseSensitive = true)
     {
-        $substringLength = mb_strlen($substring, $this->encoding);
+        $substringLength = \mb_strlen($substring, $this->encoding);
-        $startOfStr = mb_substr($this->str, 0, $substringLength,
+        $startOfStr = \mb_substr($this->str, 0, $substringLength,
             $this->encoding);
 
         if (!$caseSensitive) {
-            $substring = mb_strtolower($substring, $this->encoding);
+            $substring = \mb_strtolower($substring, $this->encoding);
-            $startOfStr = mb_strtolower($startOfStr, $this->encoding);
+            $startOfStr = \mb_strtolower($startOfStr, $this->encoding);
         }
 
         return (string) $substring === $startOfStr;
@@ -1193,7 +1192,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
             $length = $end - $start;
         }
 
-        $str = mb_substr($this->str, $start, $length, $this->encoding);
+        $str = \mb_substr($this->str, $start, $length, $this->encoding);
 
         return static::create($str, $this->encoding);
     }
@@ -1214,19 +1213,30 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         }
 
         // mb_split errors when supplied an empty pattern in < PHP 5.4.13
-        // and current versions of HHVM (3.8 and below)
+        // and HHVM < 3.8
         if ($pattern === '') {
             return array(static::create($this->str, $this->encoding));
         }
 
-        $regexEncoding = mb_regex_encoding();
+        $regexEncoding = $this->regexEncoding();
-        mb_regex_encoding($this->encoding);
+        $this->regexEncoding($this->encoding);
 
         // mb_split returns the remaining unsplit string in the last index when
         // supplying a limit
         $limit = ($limit > 0) ? $limit += 1 : -1;
-        $array = mb_split($pattern, $this->str, $limit);
+
-        mb_regex_encoding($regexEncoding);
+        static $functionExists;
+        if ($functionExists === null) {
+            $functionExists = function_exists('\mb_split');
+        }
+
+        if ($functionExists) {
+            $array = \mb_split($pattern, $this->str, $limit);
+        } else if ($this->supportsEncoding()) {
+            $array = \preg_split("/$pattern/", $this->str, $limit);
+        }
+
+        $this->regexEncoding($regexEncoding);
 
         if ($limit > 0 && count($array) === $limit) {
             array_pop($array);
@@ -1251,7 +1261,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
     public function substr($start, $length = null)
     {
         $length = $length === null ? $this->length() : $length;
-        $str = mb_substr($this->str, $start, $length, $this->encoding);
+        $str = \mb_substr($this->str, $start, $length, $this->encoding);
 
         return static::create($str, $this->encoding);
     }
@@ -1283,11 +1293,11 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         $stringy->str = preg_replace_callback(
             '/[\S]/u',
             function ($match) use ($encoding) {
-                if ($match[0] == mb_strtoupper($match[0], $encoding)) {
+                if ($match[0] == \mb_strtoupper($match[0], $encoding)) {
-                    return mb_strtolower($match[0], $encoding);
+                    return \mb_strtolower($match[0], $encoding);
                 }
 
-                return mb_strtoupper($match[0], $encoding);
+                return \mb_strtoupper($match[0], $encoding);
             },
             $stringy->str
         );
@@ -1415,7 +1425,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function toLowerCase()
     {
-        $str = mb_strtolower($this->str, $this->encoding);
+        $str = \mb_strtolower($this->str, $this->encoding);
 
         return static::create($str, $this->encoding);
     }
@@ -1458,7 +1468,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function toTitleCase()
     {
-        $str = mb_convert_case($this->str, MB_CASE_TITLE, $this->encoding);
+        $str = \mb_convert_case($this->str, \MB_CASE_TITLE, $this->encoding);
 
         return static::create($str, $this->encoding);
     }
@@ -1471,7 +1481,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function toUpperCase()
     {
-        $str = mb_strtoupper($this->str, $this->encoding);
+        $str = \mb_strtoupper($this->str, $this->encoding);
 
         return static::create($str, $this->encoding);
     }
@@ -1538,10 +1548,10 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
         }
 
         // Need to further trim the string so we can append the substring
-        $substringLength = mb_strlen($substring, $stringy->encoding);
+        $substringLength = \mb_strlen($substring, $stringy->encoding);
         $length = $length - $substringLength;
 
-        $truncated = mb_substr($stringy->str, 0, $length, $stringy->encoding);
+        $truncated = \mb_substr($stringy->str, 0, $length, $stringy->encoding);
         $stringy->str = $truncated . $substring;
 
         return $stringy;
@@ -1579,11 +1589,11 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     public function upperCaseFirst()
     {
-        $first = mb_substr($this->str, 0, 1, $this->encoding);
+        $first = \mb_substr($this->str, 0, 1, $this->encoding);
-        $rest = mb_substr($this->str, 1, $this->length() - 1,
+        $rest = \mb_substr($this->str, 1, $this->length() - 1,
             $this->encoding);
 
-        $str = mb_strtoupper($first, $this->encoding) . $rest;
+        $str = \mb_strtoupper($first, $this->encoding) . $rest;
 
         return static::create($str, $this->encoding);
     }
@@ -1632,7 +1642,8 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
                             'ῗ', 'і', 'ї', 'и', 'ဣ', 'ိ', 'ီ', 'ည်', 'ǐ', 'ი',
                             'इ', 'ی'),
             'j'    => array('ĵ', 'ј', 'Ј', 'ჯ', 'ج'),
-            'k'    => array('ķ', 'ĸ', 'к', 'κ', 'Ķ', 'ق', 'ك', 'က', 'კ', 'ქ', 'ک'),
+            'k'    => array('ķ', 'ĸ', 'к', 'κ', 'Ķ', 'ق', 'ك', 'က', 'კ', 'ქ',
+                            'ک'),
             'l'    => array('ł', 'ľ', 'ĺ', 'ļ', 'ŀ', 'л', 'λ', 'ل', 'လ', 'ლ'),
             'm'    => array('м', 'μ', 'م', 'မ', 'მ'),
             'n'    => array('ñ', 'ń', 'ň', 'ņ', 'ʼn', 'ŋ', 'ν', 'н', 'ن', 'န',
@@ -1768,7 +1779,7 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
     private function applyPadding($left = 0, $right = 0, $padStr = ' ')
     {
         $stringy = static::create($this->str, $this->encoding);
-        $length = mb_strlen($padStr, $stringy->encoding);
+        $length = \mb_strlen($padStr, $stringy->encoding);
 
         $strLength = $stringy->length();
         $paddedLength = $strLength + $left + $right;
@@ -1777,9 +1788,9 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
             return $stringy;
         }
 
-        $leftPadding = mb_substr(str_repeat($padStr, ceil($left / $length)), 0,
+        $leftPadding = \mb_substr(str_repeat($padStr, ceil($left / $length)), 0,
             $left, $stringy->encoding);
-        $rightPadding = mb_substr(str_repeat($padStr, ceil($right / $length)),
+        $rightPadding = \mb_substr(str_repeat($padStr, ceil($right / $length)),
             0, $right, $stringy->encoding);
 
         $stringy->str = $leftPadding . $stringy->str . $rightPadding;
@@ -1795,12 +1806,61 @@ class Stringy implements Countable, IteratorAggregate, ArrayAccess
      */
     private function matchesPattern($pattern)
     {
-        $regexEncoding = mb_regex_encoding();
+        $regexEncoding = $this->regexEncoding();
-        mb_regex_encoding($this->encoding);
+        $this->regexEncoding($this->encoding);
 
-        $match = mb_ereg_match($pattern, $this->str);
+        $match = \mb_ereg_match($pattern, $this->str);
-        mb_regex_encoding($regexEncoding);
+        $this->regexEncoding($regexEncoding);
 
         return $match;
     }
+
+    /**
+     * Alias for mb_ereg_replace with a fallback to preg_replace if the
+     * mbstring module is not installed.
+     */
+    private function eregReplace($pattern, $replacement, $string, $option = 'msr')
+    {
+        static $functionExists;
+        if ($functionExists === null) {
+            $functionExists = function_exists('\mb_split');
+        }
+
+        if ($functionExists) {
+            return \mb_ereg_replace($pattern, $replacement, $string, $option);
+        } else if ($this->supportsEncoding()) {
+            $option = str_replace('r', '', $option);
+            return \preg_replace("/$pattern/u$option", $replacement, $string);
+        }
+    }
+
+    /**
+     * Alias for mb_regex_encoding which default to a noop if the mbstring
+     * module is not installed.
+     */
+    private function regexEncoding()
+    {
+        static $functionExists;
+
+        if ($functionExists === null) {
+            $functionExists = function_exists('\mb_regex_encoding');
+        }
+
+        if ($functionExists) {
+            $args = func_get_args();
+            return call_user_func_array('\mb_regex_encoding', $args);
+        }
+    }
+
+    private function supportsEncoding()
+    {
+        $supported = array('UTF-8' => true, 'ASCII' => true);
+
+        if (isset($supported[$this->encoding])) {
+            return true;
+        } else {
+            throw new \RuntimeExpception('Stringy method requires the ' .
+                'mbstring module for encodings other than ASCII and UTF-8');
+        }
+    }
 }

tests/StringyTest.php

@@ -2372,6 +2372,7 @@ class StringyTestCase extends PHPUnit_Framework_TestCase
             array('foo', 'bar', '[[:alpha:]]{3}', 'foo'),
             array('', '', '', '', 'msr', 'UTF-8'),
             array('bàř', 'fòô ', 'f[òô]+\s', 'bàř', 'msr', 'UTF-8'),
+            array('fòô', 'fò', '(ò)', '\\1ô', 'msr', 'UTF-8'),
             array('fòô', 'bàř', '[[:alpha:]]{3}', 'fòô', 'msr', 'UTF-8')
         );
     }