Unit Tests in Rust

Looking at that list of things to do, one seems obviously simpler than the rest and probably more useful in the short to medium term: getting the unit tests to run.

In fact, it's ridiculously easy. I'm not exactly sure where I copied this from now, but the problem is either I chose the wrong place or didn't copy it very well. The line I have which says

#[cfg(tests)]

is plural when in fact is should be singular

#[cfg(test)]

Yup, that's it. The tests now run. I'm not quite sure why Rust doesn't give a warning about this particular mistake. rust-analyzer says that the config "tests" is "disabled", but my thought had been that meant that there was a configuration "tests" which I had specifically - deliberately or accidentally - disabled, and I spent some time looking through my configuration settings before seeing enough examples on the web where it said cfg(test) that it finally sank in that I had a simple typo.

For those wondering, yes, my code under test passed first time. My test had another error in it, which is I had copied across this (extraneous) line as well which wouldn't compile:

    use alloc::collections::btree_map::Values;

And now I get this output:

   Compiling homer_rust v0.1.0 (/home/gareth/Projects/IgnoranceBlog/homer_rust)
    Finished test [unoptimized + debuginfo] target(s) in 0.32s
     Running unittests src/lib.rs (target/debug/deps/homer_rust-6186d6a57da04f90)

running 1 test
test tests::test_set_4_in_1_from_0 ... ok

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s

   Doc-tests homer_rust

running 0 tests

test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s

This is chattier than I would like, but Rust seems to be that way. Also, for those scoring at home, it's worth noting that if I had had this working at the time, I would have written four or five tests to ensure I wrote the correct code. After the fact, especially with my application now working, I'm not going to bother.

This is checked in as RUST_BARE_METAL_TEST_NOT_TESTS.