fix external docs for exported macros

[vxpm]

macros annotated with #[macro_export] are documented at the root of the crate, yet externalDocs was returning a path which considered it to be documented at the module it's defined in. this PR fixes that.

example:

• before: externalDocs for println! was returning https://doc.rust-lang.org/nightly/std/macros/macro.println.html
• after: externalDocs for println! returns https://doc.rust-lang.org/nightly/std/macro.println.html

[ChayimFriedman2]

Please add a test.

[vxpm]

I'm not very familiar with the fixtures used in rust-analyzer's tests so I might be doing something wrong here, but the following test returns no links at all:

#[test]
fn external_docs_macro_export() {
    check_external_docs(
        r#"
//- /main.rs crate:foo
pub mod inner {
    #[macro_export]
    macro_rules my_macro! {
        () => {};
    }
}

fn main() {
    inner::my_m$0acro!();
}
        "#,
        Some("/home/user/project"),
        Some(expect![[r#"https://docs.rs/foo/*/foo/macro.my_macro.html"#]]),
        Some(expect![[r#"file:///home/user/project/doc/foo/macro.my_macro.html"#]]),
        Some("/sysroot"),
    );
}

Seeing as there are no other tests in the file which define macro_rules, is there something else I need to do to make the analysis work?

[ChayimFriedman2]

You made two mistakes: misplaced the !, and forgot that #[macro_export]ed macros resolve under the crate root. The fixed code is this:

#[test]
fn external_docs_macro_export() {
    check_external_docs(
        r#"
//- /main.rs crate:foo
pub mod inner {
    #[macro_export]
    macro_rules! my_macro {
        () => {};
    }
}

fn main() {
    my_macro$0!();
}
        "#,
        Some("/home/user/project"),
        Some(expect![[r#"https://docs.rs/foo/*/foo/macro.my_macro.html"#]]),
        Some(expect![[r#"file:///home/user/project/doc/foo/macro.my_macro.html"#]]),
        Some("/sysroot"),
    );
}

And yeah, I agree that debugging incorrect code in our tests is harder that it should be (although the highlighting helps - if it isn't highlighted correctly, there's probably an error somewhere).

[vxpm]

oops - macro_rules syntax always trips me up, and the wrong path is a leftover from me trying to figure out what's wrong. thanks, such silly mistakes.

[ChayimFriedman2]

Can you squash please?

[vxpm]

done!

[ChayimFriedman2]

Thanks!