Respect ${CARGO,RUSTUP}_HOME for tooltip relative dirs

[Xanewok]

In principle, I'd say I prefer absolute paths for references to outside of the project root (or at least relative to ${CARGO,RUSTUP_HOME} in this case) but it's what we test against now and didn't want to cause any change in behaviour now.

I'd appreciate more eyes looking at this: @ehuss @alexheretic @aloucks

Should fix Rust CI failure rust-lang/rust#56924 (there, we map .cargo to /cargo and the old logic only remapped paths starting from .cargo).

[aloucks]

I toyed around with absolute paths when I originally added the module paths to tooltips. The full paths could be quite large and I came to the conclusion that extra noise wasn't worth it. The most useful part would be at the bottom/end. VSCode also has a pretty limited-width tooltip and it almost always word wrapped. It looks pretty bad.

/home/user/.cargo/registry/src/github.com-
1ecc6299db9ec823/smallvec-0.6.2/lib.rs

vs

smallvec-0.6.2/lib.rs

The crate name and version, and path within the crate is both functional and doesn't overwhelm the user.

[aloucks]

I've always followed the assert(expected, actual) convention that junit uses, but I guess the assert macro doesn't make that distinction.

e.g. https://junit.org/junit4/javadoc/4.12/org/junit/Assert.html#assertEquals(long,%20long)

[Xanewok]

I certainly didn't mean to force any changes! It's just that it read better for me due to symmetry with assigning above, so the variable is on the left side and checked expression is on the right (and the macro doesn't make any distinction, as you've said):

let var = compute_expr();
assert_eq!(var, val_of_expr);

[alexheretic]

Tbf the general consensus is assert_eq!(actual, expected) you can see this in rust docs

// len docs
let mut v = HashSet::new();
assert_eq!(v.len(), 0);
v.insert(1);
assert_eq!(v.len(), 1);

I think most language/test apis use this way too, junit didn't but hamcrest & assertj, for example, do.

[Xanewok]

(...) VSCode also has a pretty limited-width tooltip and it almost always word wrapped. It looks pretty bad.

Yeah, I can see that now. I agree that the shortened version looks a lot easier to digest; I guess people should already know where they have their {CARGO,RUSTUP}_HOME set up.

I'm wondering if it'd make sense to make it configurable and allow users to opt-in to the full path. It may sound silly but I know I'd like to know where exactly is the file the module is referred from 😅

[alexheretic]

lgtm

[Xanewok]

Thanks!