Nobody likes upgrading a system and getting new errors that weren't there before.
I'm using WWW::Mechanize because it works really well and it's maintained and extensively used in regression testing.
I already have a quick script to install OpenACS/.LRN from scratch only using the web interface (as a human with the browser would do).
You can find it here: http://e-lane.org/pub/openacs_assessment_regression_tests
It's not polished but it works quite well.
Some said to use TCL Webtest. But many people including me totally NOT like it
The links to the perl WWW::Mechanize:
Web Testing with HTTP::Recorder (so you just have to browse the site to get a test script)
There are other options like:
http://httpunit.sourceforge.net/ (also with http://junit.sourceforge.net/)
More about Web Testing in this slashdot discussion:
Some past references:
.LRN can now be installed automatically with the help of tclwebtest (I can't get the scripts. Anybody knows where to get them?)
Do you also feel that OpenACS/.LRN needs some real regression testing?
What do you suggest?