frr

This is incredibly funny to me, because that's (almost) exactly how some of our other tests work :D (Almost: we have a full-featured command shell and just use that for testing) Shell bindings: https://github.com/FRRouting/frr/blob/master/tests/ospf6d/te... Input: https://github.com/FRRouting/frr/blob/master/tests/ospf6d/te... Expected output: https://github.com/FRRouting/frr/blob/master/tests/ospf6d/te... Absolutely agree this is a great option to have for some kinds of tests.

Here's another example of unit tests for hash tables (and RB-trees and skiplists and…) https://github.com/FRRouting/frr/blob/master/tests/lib/test_... (this file is #include'd from another, with some #define set up:) https://github.com/FRRouting/frr/blob/master/tests/lib/test_... The "tribe" of C developers with distaste for the preprocessor will absolutely hate how this is written. But it works and caught real issues. It doesn't use an external fuzzing tool but rather a deterministic PRNG (see prng_* calls) to get a good mix of call combinations. Coverage analysis was done to make sure it reaches everywhere. (disclaimer: I wrote this. And it did catch bugs. Also it really should have a lot of comments.)

I don't think it's possible to get away with fundamentally no cancellation support, there are enough edge cases that need it even if most applications don't have such edge cases. FWIW, this was also painful to do across threads in our C event loop, but there was no way around the fact that we needed it (cf. https://github.com/FRRouting/frr/blob/56d994aecab08b9462f2c8... )

I agree that the debugging and maintenance experience is much better that way, but it comes at the cost of very poor "DX". We, discussing this here on this thread, understand what's going on. But sadly at least for the projects I'm involved in, the average developer does not. TBH, rather than fancy high-meta generic support, I'd be much more appreciative of ISO C adding something like "_Include" to the preprocessor, e.g. #define DEFINE_MY_WRAPPER(foo, bar) _Include("wrapper.h") /* "foo", "bar" remain accessible in wrapper.h */ I tried implementing this in GCC but didn't get very far, it runs a bit counter to how includes are handled currently. P.S.: I ended up doing this https://github.com/FRRouting/frr/pull/15876/files#diff-90783... instead; a tool that can be invoked to expand some DEFINE_FOO if needed for debugging. It's not us

<300 lines? Peanuts! ;D https://github.com/FRRouting/frr/blob/master/lib/typesafe.h https://docs.frrouting.org/projects/dev-guide/en/latest/list...

https://www.youtube.com/watch?v=8psFQCEgA18 The fact that our CLI client (talking to multiple daemons) can pull and display log messages from the daemons, live, without breaking interactive user input. It's such a simple idea, not quite as simple to implement, but such a massive UX improvement. https://github.com/FRRouting/frr/blob/aa6ceeeb5b1f92280ee797...