Author here. This post is a rewrite of the previous Unit Testing [1] and Integration Tests [2] posts. It creates a custom test framework that runs test functions inside QEMU, so that they run in a realistic environment (compared to running on the host system).
The new test framework directly works with `cargo xtest`, which brings the project closer to using standard cargo programs for building, testing, and running. The last remaining step is the `std` Aware Cargo RFC [3]. When the RFC is merged and implemented, cargo-xbuild will no longer be needed and the familiar cargo build, cargo run, and cargo test commands will just work, including IDE integration.
Just wanted to say thanks so much for your blog posts! I have been working on a medical device in no_std Rust and your articles have been super helpful in setting up a robust unit test suite. I have been trying to hack at the utest crate and get on-device integration tests running again for quite some time... good to know there is movement on the custom test runner front :)
It's the first time that I hear about Rust on medical devices. Sounds really interesting! I'm glad to hear that my blog was useful to you!
> I have been trying to hack at the utest crate and get on-device integration tests running again for quite some time... good to know there is movement on the custom test runner front :)
The custom test framework feature of Rust was silently introduced in https://github.com/rust-lang/rust/pull/53410 and I didn't know that it even existed a month ago. But it works really well and seems like a good solution for your problem.
Other than that, there is ongoing work for custom allocator support in collections: https://github.com/rust-lang/rust/issues/42774. Maybe that's what you meant with tracking the allocators at the type level?
It's of course also possible to create own fallible collection types, for example as a wrapper around the normal liballoc and try_reserve.
I did not write my own stdlib since I didn't need it yet (the blog has no heap allocation yet). And I think infallible allocation is good enough for the beginning.
But I think it should be possible to create a fallible wrapper library around liballoc quite easily. We only need an appropriate call to try_reserve for every wrapped function. For example, `push` would do a `try_reserve(1)` before calling the push function of liballoc.
[1]: https://os.phil-opp.com/unit-testing/ [2]: https://os.phil-opp.com/integration-tests/
The new test framework directly works with `cargo xtest`, which brings the project closer to using standard cargo programs for building, testing, and running. The last remaining step is the `std` Aware Cargo RFC [3]. When the RFC is merged and implemented, cargo-xbuild will no longer be needed and the familiar cargo build, cargo run, and cargo test commands will just work, including IDE integration.
[3]: https://github.com/rust-lang/rfcs/pull/2663