I've found a handful of bugs in the tag libraries that have been a real nuisance to isolate. I wrote a MgnlTagTestCase to help create the necessary mock objects to test the existing tags unchanged (i.e. test them as they spit out content to the JspWriter - and verify that the output is what is expected)

In the attached patch, I also have a test started for the cms:out tag - this test case only covers the UUID link output that I logged in another issue ( http://jira.magnolia.info/browse/MAGNOLIA-1978 )

This change should not interfere with anything else - it just adds the ability to more easily generate tests for the tag library functions.