rustdoc: links from items in a trait impl are inconsistent

[mockersf]

Depending on where the struct implementing a trait is coming from, or the current page, the items in a trait impl are not linking to the same thing:

item	trait page, implementors	trait page, implementations on Foreign Types	struct page, trait implementations
function	link to current impl	link to first impl in the list	link to trait def
default function	not present	not present	link to trait def
default function with custom impl	link to current impl	link to trait def	link to trait def
constant	link to current impl	link to trait def	link to trait def
associated type	link to current impl	link to trait def	link to trait def
	missing link to trait def	function link wrong + missing link to current impl	missing link to current impl

rust code with those cases

pub trait MyTrait {
    type Assoc;
    const VALUE: u32;
    fn trait_function(&self);
    fn defaulted(&self) {}
    fn defaulted_override(&self) {}
}

impl MyTrait for String {
    /// will link to trait def
    type Assoc = ();
    /// will link to trait def
    const VALUE: u32 = 5;
    /// will link to first foreign implementor
    fn trait_function(&self) {}
    /// will link to trait def
    fn defaulted_override(&self) {}
}

impl MyTrait for Vec<u8> {
    /// will link to trait def
    type Assoc = ();
    /// will link to trait def
    const VALUE: u32 = 5;
    /// will link to first foreign implementor
    fn trait_function(&self) {}
    /// will link to trait def
    fn defaulted_override(&self) {}
}

impl MyTrait for MyStruct {
    /// in trait page, will link to current impl
    ///
    /// in struct page, will link to trait def
    type Assoc = bool;
    /// in trait page, will link to current impl
    ///
    /// in struct page, will link to trait def
    const VALUE: u32 = 20;
    /// in trait page, will link to current impl
    ///
    /// in struct page, will link to trait def
    fn trait_function(&self) {}
    /// in trait page, will link to current impl
    ///
    /// in struct page, will link to trait def
    fn defaulted_override(&self) {}
}

pub struct MyStruct;

In this PR, I fixed all links to target the trait definition, and added an anchor-link to the current implementation appearing on mouse hover.

[rust-highfive]

Some changes occurred in HTML/CSS/JS.

cc @GuillaumeGomez

[rust-highfive]

r? @GuillaumeGomez

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[GuillaumeGomez]

Looks good to me, thanks! Can you add a test in src/test/rustdoc to ensure that it works as expected please? You already wrote the file with all the cases so that should be quick. ;)

[mockersf]

test added 👍

[GuillaumeGomez]

I'm lost here: what's the point of testing that this exists on the trait when we're currently on a trait implementation on a type?

[mockersf]

this is on the struct impl for the trait on the trait doc page. the method.defaulted_override-3 is targeting the impl, not the trait itself

[GuillaumeGomez]

Apparently not because the href you test is "#method.defaulted_override".

[mockersf]

oh right, in the h4 with id method.defaulted_override-3, there is now the function name (class fnname that links to it's trait definition, so #method.defaulted_override, and anchor (class anchor) that links to itself (the line under this one)

this pr makes it so that every item in a trait impl is that way

[GuillaumeGomez]

That part makes sense, but why are you testing that on the trait page whereas we "are" (so to speak) on the type?

[mockersf]

as the type implements the trait, it is present on both page

[bors]

☔ The latest upstream changes (presumably #82873) made this pull request unmergeable. Please resolve the merge conflicts.

[jyn514]

ping @GuillaumeGomez - this is waiting on your review.

@mockersf do you mind fixing the merge conflict in the meantime?

[GuillaumeGomez]

Still in my review list. :)

[mockersf]

@mockersf do you mind fixing the merge conflict in the meantime?

fixed!

[GuillaumeGomez]

Thanks!

@bors: r+

[bors]

📌 Commit e36ca09 has been approved by GuillaumeGomez

[bors]

⌛ Testing commit e36ca09 with merge b203b0d...

[bors]

☀️ Test successful - checks-actions
Approved by: GuillaumeGomez
Pushing b203b0d to master...