Auto merge of #55682 - GuillaumeGomez:primitive-sidebar-link-gen, r=QuietMisdreavus

Fixes primitive sidebar link generation

Fixes #50746.
Fixes #55656.

r? @QuietMisdreavus

src/librustdoc/html/render.rs

@@ -4249,13 +4249,30 @@ impl<'a> fmt::Display for Sidebar<'a> {
     }
 }
 
-fn get_methods(i: &clean::Impl, for_deref: bool) -> Vec<String> {
+fn get_next_url(used_links: &mut FxHashSet<String>, url: String) -> String {
+    if used_links.insert(url.clone()) {
+        return url;
+    }
+    let mut add = 1;
+    while used_links.insert(format!("{}-{}", url, add)) == false {
+        add += 1;
+    }
+    format!("{}-{}", url, add)
+}
+
+fn get_methods(
+    i: &clean::Impl,
+    for_deref: bool,
+    used_links: &mut FxHashSet<String>,
+) -> Vec<String> {
     i.items.iter().filter_map(|item| {
         match item.name {
             // Maybe check with clean::Visibility::Public as well?
             Some(ref name) if !name.is_empty() && item.visibility.is_some() && item.is_method() => {
                 if !for_deref || should_render_item(item, false) {
-                    Some(format!("<a href=\"#method.{name}\">{name}</a>", name = name))
+                    Some(format!("<a href=\"#{}\">{}</a>",
+                                 get_next_url(used_links, format!("method.{}", name)),
+                                 name))
                 } else {
                     None
                 }
@@ -4285,14 +4302,21 @@ fn sidebar_assoc_items(it: &clean::Item) -> String {
     let mut out = String::new();
     let c = cache();
     if let Some(v) = c.impls.get(&it.def_id) {
+        let mut used_links = FxHashSet::default();
+
+        {
+            let used_links_bor = Rc::new(RefCell::new(&mut used_links));
             let ret = v.iter()
                        .filter(|i| i.inner_impl().trait_.is_none())
-                   .flat_map(|i| get_methods(i.inner_impl(), false))
+                       .flat_map(move |i| get_methods(i.inner_impl(),
+                                                      false,
+                                                      &mut used_links_bor.borrow_mut()))
                        .collect::<String>();
             if !ret.is_empty() {
                 out.push_str(&format!("<a class=\"sidebar-title\" href=\"#methods\">Methods\
                                        </a><div class=\"sidebar-links\">{}</div>", ret));
             }
+        }
 
         if v.iter().any(|i| i.inner_impl().trait_.is_some()) {
             if let Some(impl_) = v.iter()
@@ -4316,7 +4340,9 @@ fn sidebar_assoc_items(it: &clean::Item) -> String {
                         out.push_str("</a>");
                         let ret = impls.iter()
                                        .filter(|i| i.inner_impl().trait_.is_none())
-                                       .flat_map(|i| get_methods(i.inner_impl(), true))
+                                       .flat_map(|i| get_methods(i.inner_impl(),
+                                                                 true,
+                                                                 &mut used_links))
                                        .collect::<String>();
                         out.push_str(&format!("<div class=\"sidebar-links\">{}</div>", ret));
                     }
@@ -4324,6 +4350,7 @@ fn sidebar_assoc_items(it: &clean::Item) -> String {
             }
             let format_impls = |impls: Vec<&Impl>| {
                 let mut links = FxHashSet::default();
+
                 impls.iter()
                      .filter_map(|i| {
                          let is_negative_impl = is_negative_impl(i.inner_impl());

src/test/rustdoc/sidebar-link-generation.rs

@@ -0,0 +1,23 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![crate_name = "foo"]
+
+// @has foo/struct.SomeStruct.html '//*[@class="sidebar-links"]/a[@href="#method.some_fn-1"]' \
+//          "some_fn"
+pub struct SomeStruct<T> { _inner: T }
+
+impl SomeStruct<()> {
+    pub fn some_fn(&self) {}
+}
+
+impl SomeStruct<usize> {
+    pub fn some_fn(&self) {}
+}