* Jeroen Dekkers:
For sufficiently complex software, a suite of regression tests is extremely helpful for making modifications. However, in some areas, there is a strong interest in proprietary test suites (in the GCC context, for example). Forced publication of test suites would unduly extend the scope of software copyright. That's why I'm not sure if anything should be done about this.
Because you don't distribute (or propagate in GPLv3 terms) anything when running a test suite on a program, I don't see how the GPL could enforce anything about test suites.
The same argument could be applied to the encryption keys and build scripts, but providing them is explicitly required.