[weebull]

This is something I've yet to see a software testing framework do. Compare the results of two different implementations separated in time. i.e. two different revisions out of source control, using one as the golden reference for the other.

[CHY872]

bazhenov/tango does something like this for performance tests, basically to counter system behaviour you run the old and new implementation at the same time.

[adregan]

Isn’t that kind of what snapshot tests can do?