Looking at this, I can now see why a test function nested in another function (see [0] and [1]) doesn’t work. I’ve tried dabbling with the Rust compiler to see if I could help fix this, but it takes 30 minutes to compile rustc and I couldn’t figure out how to reduce those compile times (each time I changed 1 line and wanted to test, I had to wait 30 minutes to build). How do people work on rustc (or internal Rust libraries, like libsyntax) without waiting for 30 minute builds after every minor change?
[0]: https://github.com/rust-lang/rust/issues/36629
[1]: https://github.com/rust-lang/rfcs/issues/612