(Originally posted on GitHub, sorry about that.)
The Rust exercise Resistor-Color suggests to use dependencies with procedural macros, which increase the compile times a lot, making the tests time out.
There is a past issue about this on GitHub and it was fixed by disabling the online tests for this exercise all together.
But the tests are now running again online and there was already a mentoring request where someone was confused why their tests are not passing.
It seems to me the tests were enabled again by this large refactoring commit. I’m assuming this wasn’t intentional and just slipped through the cracks of the noisy diff.
Edit: Maybe it’s worth noting that this exercise can easily be solved without the dependencies and the tests will pass. It’s just that the point of the exercise seems to be to introduce people to these external dependencies, so it would be weird to tell people not to use them to make the tests pass.