1. 1. 1. Problem

I have found an inaccessible course due to a mod/url that had the form:

cfile:///C:/Users/[...]

and produced this stack trace:

Exception found: L'URL no és vàlid

• line 565 of /mod/url/locallib.php: call to moodle_url->__construct()
• line 223 of /mod/url/lib.php: call to url_guess_icon()
  [...]

in Moodle 3.10.

Maybe it was accepted in Moodle 3.8 or before and upgrading to Moodle 3.10 made this course inaccessible. It was an old course, from 3 years ago.

1. 1. 1. Context

The code that produces this exception and breaks the course, is just to calculate which icon to show beside the URL. So, it is not a critical point.

1. 1. 1. Proposal

Make this piece of code behave as "best effort".

In Moodle 3.10, the function locallib.php::url_guess_icon($fullurl, $size = null)

the breaking part is:

$moodleurl = new moodle_url($fullurl); //<--- breaking line
$fullurl = $moodleurl->out_omit_querystring();
$icon = file_extension_icon($fullurl, $size);
$htmlicon = file_extension_icon('.htm', $size);
$unknownicon = file_extension_icon('', $size);

// We do not want to return those icon types, the module icon is more appropriate.
if ($icon === $unknownicon || $icon === $htmlicon)

{ return null; }

return $icon;
}

//// end of piece of code

I propose to catch the exception and make sure the site works properly always and use the module icon instead.

Like:

try { r$moodleurl = new moodle_url($fullurl); } catch(moodle_exception $e) { return null; }

$fullurl = $moodleurl->out_omit_querystring();
[...]