The Quiz Extension has a lot of long lines, that should be wrapped, split and reformatted to improve the code readability.
See also: https://www.mediawiki.org/wiki/Manual:Coding_conventions#Line_continuation
The Quiz extension was created by a volunteer and is currently installed on several WMF projects, such as Wikiversity.
Getting started
Install mediawiki locally. It is easiest (often) to use vagrant for this. Quiz is not available as a role in vagrant, so follow these directions to manually add lines to LocalSettings.php in vagrant, and include the line
require_once("$IP/extensions/Quiz/Quiz.php");You can test that the extension is working by adding a sample quiz to your test wiki in wikitext. The quiz syntax is well documented here.
You can find the quiz extension in the vagrant repository by navigating to mediawiki/extensions/Quiz. If you haven't already, you will need to set up git, gerrit, and git-review, and install a gerrit hook to begin submitting commits to the Quiz extension.