I came across the ApprovalTests.com framework today and am curious how it would be classified. I am familiar with concepts of Unit Tests, functional tests, and user acceptance testing, but this seems to be a different kind of testing as it is based on matching test outputs against pre-approved outputs that have been verified or generated by a human. I want to call it verification or validation testing or maybe automated User Acceptance Testing, but I am curious if there is an official term for a framework that uses previously approved output values instead of just assertions on primitive types.
Also are there any other frameworks that use a similar approach? It appears that ApprovalTests has integrated well with Eclipse/Visual Studio, data serializers/viewers, and various Diff tools, but I would be interested in seeing if and how anyone else has done this type of testing.