Write functional test cases for the backends

[laena]

These should be run by Travis, too (to check that a changeset not only compiles, but also does not break functionality).

They can be limited to C++ backend code.

Any ideas for easy-to-integrate test frameworks?

[rakhimov]

I thought you already had GoogleTests (at least it is somewhere in the wiki mentioned)?

[laena]

Yes, but it was used only as a programming help in very early versions. I think it would make sense to write clean test cases from scratch.

There are tests for the entire software stack including frontend, but no nice, isolated unit tests for the backends.