I was thinking about creating some QUnit tests for one of my user scripts and also for a gadget, but AFAIK there is no standard way to do this.
The [[Special:JavaScriptTest/qunit]] only says "This function has not been enabled on this wiki." but maybe it should provide a way to let users to run their QUnit tests, e.g. by defining the page name of a script, or some URL param.
For example, if a wiki has some gadgets the users (mainly sysops and gadget editors) could follow links to pages such as
[[Special:JavaScriptTest/qunit/<some name related to the gadget>]]
(or use a URL param, as in "Special:JavaScriptTest/qunit?gadget=foo") as soon as a gadget is changed, to ensure the latest changes didn't broke anything.
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