[DDC-1900] Throw exception when overwriting internal function.

lib/Doctrine/ORM/Configuration.php

@@ -380,6 +380,10 @@ class Configuration extends \Doctrine\DBAL\Configuration
      */
     public function addCustomStringFunction($name, $className)
     {
+        if (Query\Parser::isInternalFunction($name)) {
+            throw ORMException::overwriteInternalDQLFunctionNotAllowed($name);
+        }
+
         $this->_attributes['customStringFunctions'][strtolower($name)] = $className;
     }
 
@@ -410,7 +414,9 @@ class Configuration extends \Doctrine\DBAL\Configuration
      */
     public function setCustomStringFunctions(array $functions)
     {
-        $this->_attributes['customStringFunctions'] = array_change_key_case($functions);
+        foreach ($functions as $name => $className) {
+            $this->addCustomStringFunction($name, $className);
+        }
     }
 
     /**
@@ -425,6 +431,10 @@ class Configuration extends \Doctrine\DBAL\Configuration
      */
     public function addCustomNumericFunction($name, $className)
     {
+        if (Query\Parser::isInternalFunction($name)) {
+            throw ORMException::overwriteInternalDQLFunctionNotAllowed($name);
+        }
+
         $this->_attributes['customNumericFunctions'][strtolower($name)] = $className;
     }
 
@@ -455,7 +465,9 @@ class Configuration extends \Doctrine\DBAL\Configuration
      */
     public function setCustomNumericFunctions(array $functions)
     {
-        $this->_attributes['customNumericFunctions'] = array_change_key_case($functions);
+        foreach ($functions as $name => $className) {
+            $this->addCustomNumericFunction($name, $className);
+        }
     }
 
     /**
@@ -470,6 +482,10 @@ class Configuration extends \Doctrine\DBAL\Configuration
      */
     public function addCustomDatetimeFunction($name, $className)
     {
+        if (Query\Parser::isInternalFunction($name)) {
+            throw ORMException::overwriteInternalDQLFunctionNotAllowed($name);
+        }
+
         $this->_attributes['customDatetimeFunctions'][strtolower($name)] = $className;
     }
 
@@ -500,7 +516,9 @@ class Configuration extends \Doctrine\DBAL\Configuration
      */
     public function setCustomDatetimeFunctions(array $functions)
     {
-        $this->_attributes['customDatetimeFunctions'] = array_change_key_case($functions);
+        foreach ($functions as $name => $className) {
+            $this->addCustomDatetimeFunction($name, $className);
+        }
     }
 
     /**

lib/Doctrine/ORM/ORMException.php

@@ -149,4 +149,9 @@ class ORMException extends Exception
     {
         return new self("The identifier $fieldName is missing for a query of " . $className);
     }
+
+    public static function overwriteInternalDQLFunctionNotAllowed($functionName)
+    {
+        return new self("It is not allowed to overwrite internal function '$functionName' in the DQL parser through user-defined functions.");
+    }
 }

lib/Doctrine/ORM/Query/Parser.php

@@ -136,6 +136,22 @@ class Parser
      */
     private $_identVariableExpressions = array();
 
+    /**
+     * Check if a function is internally defined. Used to prevent overwriting
+     * of built-in functions through user-defined functions.
+     *
+     * @param string $functionName
+     * @return bool
+     */
+    static public function isInternalFunction($functionName)
+    {
+        $functionName = strtolower($functionName);
+
+        return isset(self::$_STRING_FUNCTIONS[$functionName])
+            || isset(self::$_DATETIME_FUNCTIONS[$functionName])
+            || isset(self::$_NUMERIC_FUNCTIONS[$functionName]);
+    }
+
     /**
      * Creates a new query parser object.
      *