Description:
------------
I was writing unit tests (using PHPUnit) to validate my email validation functionality, which simply returned the result of filter_var($var, FILTER_SANITIZE_EMAIL). I tested all of the characters allowed in the documentation, but the / character was stripped out. I expected / to be a valid character. This is what the documentation states:

FILTER_SANITIZE_EMAIL | Remove all characters except letters, digits and !#$%&'*+-/=?^_`{|}~@.[].

Found at http://php.net/manual/en/filter.filters.sanitize.php

I then verified that this problem exists in the latest windows version as well (ran from command line with -r flag).

This is either a problem with the implementation of the function, or inaccurate documentation. I briefly tried to interpret RFC 5321/RFC5322, but couldn't find this particular case.

Test script:
---------------
<?php
echo "Output: " . filter_var('!#$%&\'*+-=?^_`{|}~@.[]', FILTER_SANITIZE_EMAIL);
echo "\nOutput: " . filter_var('!#$%&\'*+-=?^_`{|}~@.[]/', FILTER_SANITIZE_EMAIL);
echo "\nOutput: " . filter_var('/', FILTER_SANITIZE_EMAIL);
?>

Expected result:
----------------
Output: !#$%&'*+-=?^_`{|}~@.[]
Output: !#$%&'*+-=?^_`{|}~@.[]/
Output: /


Actual result:
--------------
Output: !#$%&'*+-=?^_`{|}~@.[]
Output: !#$%&'*+-=?^_`{|}~@.[]
Output: