But I think what you are saying actually is an argument for @piinbinary's idea of "static analisys". If you can't really test your change, then the other thing

But I think what you are saying actually is an argument for @piinbinary's idea of "static analisys". If you can't really test your change, then the other thing you can do is try to rationally analyse its consequences. After all thats why "hopefully there's a throrough code review". Wouldn't it be nice to automate some of that analysis? I have no idea how to go about such a thing, or whether it is even possible -- but the harder testing gets, the more attractive this option is.