A test for PHP bug 53755, FILTER_SANITIZE_STRING truncates strings with unmatched "<" character

bug53755.phpt

--TEST--
bug XXXXX FILTER_SANITIZE_STRING truncates string with single < in it.
--SKIPIF--
<?php if (!extension_loaded("filter")) die("skip"); ?>
--FILE--
<?php 
echo filter_var('four is < 6', FILTER_SANITIZE_STRING);
echo "\n";

echo filter_var("four is < 6 <script>alert('XSS');</script> yes it is", FILTER_SANITIZE_STRING);
echo "\n";

echo filter_var("four is < 6 < script >alert('XSS');< /script > yes it is", FILTER_SANITIZE_STRING);
echo "\n";
?>
--EXPECT--
four is < 6
four is < 6 alert(&#39;XSS&#39;); yes it is
four is < 6 < script >alert(&#39;XSS&#39;);< /script > yes it is