“Vari­a­tion: Sabo­teur
A Test Stub that is used to inject invalid indi­rect inputs into the SUT is often called a “Sabo­teur” because its pur­pose is to derail what­ever the SUT is try­ing to do so we can see how the SUT copes with these cir­cum­stances. The “derail­ment” can be caused by return­ing unex­pected val­ues or objects, or it can be caused by rais­ing an excep­tion or caus­ing a run­time error. Each test may either be a Sim­ple Suc­cess Test or an Expected Excep­tion Test (see Test Method) depend­ing on how the SUT is expected to behave in response to the indi­rect input.”

“RR (Dou­ble Ruby) is a test dou­ble frame­work that fea­tures a rich selec­tion of dou­ble tech­niques and a terse syntax.”

“The US pub­lic domain is filled with cre­ative works you can use any way you want to. No need to ask anyone’s per­mis­sion. No fees necessary.

You can find pho­tos, books, music, soft­ware — and more — that you’re free to recast, remix, and build upon. But how do you find these works? And how can you be sure they really are copyright-​​free?

Copy­right law is com­plex (as com­plex as the tax code, some say) and there’s a lot of mis­in­for­ma­tion and hype out there about what is and what isn’t “pub­lic domain.” It can get confusing.”

Actu­ally quite a bit of inter­est­ing meta-​​info here