Added support for MySQL CHAR_LENGTH function.

lib/DoctrineExtensions/Query/Mysql/CharLength.php

@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * DoctrineExtensions Mysql Function Pack
+ *
+ * LICENSE
+ *
+ * This source file is subject to the new BSD license that is bundled
+ * with this package in the file LICENSE.txt.
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to kontakt@beberlei.de so I can send you a copy immediately.
+ */
+
+namespace DoctrineExtensions\Query\Mysql;
+
+use Doctrine\ORM\Query\AST\Functions\FunctionNode,
+    Doctrine\ORM\Query\Lexer;
+
+/**
+ * "CHAR_LENGTH" "(" SimpleArithmeticExpression ")"
+ * 
+ * @category DoctrineExtensions
+ * @package  DoctrineExtensions\Query\Mysql
+ * @author   Metod <metod@simpel.si>
+ * @license  BSD License
+ */
+class CharLength extends FunctionNode
+{
+    private $expr;
+
+    /**
+     * @override
+     */
+    public function parse(\Doctrine\ORM\Query\Parser $parser)
+    {
+        $parser->match(Lexer::T_IDENTIFIER);
+        $parser->match(Lexer::T_OPEN_PARENTHESIS);
+
+        $this->expr1 = $parser->ArithmeticExpression();
+
+        $parser->match(Lexer::T_CLOSE_PARENTHESIS);
+    }
+
+    /**
+     * @override
+     */
+    public function getSql(\Doctrine\ORM\Query\SqlWalker $sqlWalker)
+    {
+        return 'CHAR_LENGTH('.$sqlWalker->walkArithmeticPrimary($this->expr1).')';
+    }
+}