Description:
------------
In 5.2.1 we always received the string 'png' in example 2. It seems that filter_var does not call the "__toString" (or something similar) Method at least for SimpleXMLElement objects.

Example 3 is working correctly.



Test script:
---------------
class Benutzer
 {
     protected $name;
     public function __construct( $name )
      {
         $this->name = $name;
     }
     public function __toString()
     {
         return $this->name;
     }
 }
$benutzer = new Benutzer( 'TEST' );


$xmlstring = '<?xml version="1.0" encoding="iso-8859-1"?'.'><file uuid="samplefile_1234234646sdfsdf" 

name="openengine_logo" ext="png" status="released" action="update">
    <meta>
        <attribute key="title" value="Download A"/>
        <attribute key="product_name" value="Product A"/>
        <attribute key="product_name" value="Product B"/>
        <attribute key="product_name" value="Product C"/>
        <attribute key="product_family" value="Product Family A"/>
        <attribute key="product_version" value="1.0"/>
        <attribute key="group_main" value="Group A"/>
        <attribute key="group_sub" value="Group B"/>
        <attribute key="document_type" value="Image"/>
        <attribute key="document_type" value="Video"/>
        <attribute key="document_type" value="Audio"/>
        <attribute key="language" value="en"/>
        <attribute key="language" value="de"/>
        <attribute key="description" value="This is a sample file"/>
        <attribute key="release_date" value="2003-06-04T12:30:17"/>
    </meta>
    <auth folder="YYY"/>
    <user id="XXX"/>
</file>';

$xml = simplexml_load_string($xmlstring);

echo "\n###################################################\n";
echo "Testing filter_var with SimpleXMLElement Object\n";
echo "\n###################################################\n";


echo "\nExample 1";
echo "\n----------------------------\n";
echo "DUMP XML Attribute\n\n";
echo "Output:\n";
echo $xml["ext"];
echo "\n----------------------------\n";

echo "\nExample 2";
echo "\n----------------------------\n";
echo "Output filter_var\n\n";
echo "Result:\n";
echo var_dump(filter_var($xml["ext"], FILTER_SANITIZE_STRING));
echo "\n\nPROBLEM: in former versions as 5.2.1 result has been 'png'";
echo "\n----------------------------\n";

echo "\nExample 3";
echo "\n----------------------------\n";
echo "Output filter_var with active type switching\n\n";
echo "Result:\n";
echo var_dump(filter_var((string) $xml["ext"], FILTER_SANITIZE_STRING));
echo "\n----------------------------\n";

echo "\nExample 4";
echo "\n----------------------------\n";
echo "Output user object with __toString Method\n\n";
echo "Result:\n";
echo var_dump(filter_var($benutzer, FILTER_SANITIZE_STRING));
echo "\n----------------------------\n";

Expected result:
----------------
###################################################
Testing filter_var with SimpleXMLElement Objects

###################################################

Example 1
----------------------------
DUMP XML Attribute

Output:
png
----------------------------

Example 2
----------------------------
Output filter_var

Result:
string(3) "png"


PROBLEM: in former versions as 5.2.1 result has been 'png'
----------------------------

Example 3
----------------------------
Output filter_var with active type switching

Result:
string(3) "png"

----------------------------

Example 4
----------------------------
Output user object with __toString Method

Result:
string(4) "TEST"

----------------------------


Actual result:
--------------
###################################################
Testing filter_var with SimpleXMLElement Objects

###################################################

Example 1
----------------------------
DUMP XML Attribute

Output:
png
----------------------------

Example 2
----------------------------
Output filter_var

Result:
bool(false)


PROBLEM: in former versions as 5.2.1 result has been 'png'
----------------------------

Example 3
----------------------------
Output filter_var with active type switching

Result:
string(3) "png"

----------------------------

Example 4
----------------------------
Output user object with __toString Method

Result:
string(4) "TEST"

----------------------------