Description:
------------
getimagesize returns Array for php files if you add GIF at beginning of the file.

Reproduce code:
---------------
phpgif.php

GIF
<?php 
echo "PHP CODE";
?>


test.php
<?
$image = "phpgif.php";
$image_size = getimagesize($image);
echo"<pre>";
print_r($image_size);
echo"</pre>";
?>


Expected result:
----------------
Nothing. Because phpgif.php is not a picture.

Actual result:
--------------
Array
(
    [0] => 28735
    [1] => 28776
    [2] => 1
    [3] => width="28735" height="28776"
    [channels] => 3
    [mime] => image/gif
)