rustdoc: make JS trait impls act more like HTML

6 files changed, 100 insertions, 8 deletions

diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 51cc836cd15..3cf166a3e43 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -55,7 +55,6 @@ use rustc_hir::def_id::{DefId, DefIdSet};
 use rustc_hir::Mutability;
 use rustc_middle::middle::stability;
 use rustc_middle::ty::{self, TyCtxt};
-use rustc_middle::ty::fast_reject::{DeepRejectCtxt, TreatParams};
 use rustc_span::{
     symbol::{sym, Symbol},
     BytePos, FileName, RealFileName,
diff --git a/src/librustdoc/html/render/write_shared.rs b/src/librustdoc/html/render/write_shared.rs
index 4054281f346..3e58dd96ed9 100644
--- a/src/librustdoc/html/render/write_shared.rs
+++ b/src/librustdoc/html/render/write_shared.rs
@@ -530,7 +530,11 @@ if (typeof exports !== 'undefined') {exports.searchIndex = searchIndex};
             .values()
             .flat_map(|AliasedTypeImpl { impl_, type_aliases }| {
                 let mut ret = Vec::new();
-                let trait_ = impl_.inner_impl().trait_.as_ref().map(|path| path.last().to_string());
+                let trait_ = impl_
+                    .inner_impl()
+                    .trait_
+                    .as_ref()
+                    .map(|trait_| format!("{:#}", trait_.print(cx)));
                 // render_impl will filter out "impossible-to-call" methods
                 // to make that functionality work here, it needs to be called with
                 // each type alias, and if it gives a different result, split the impl
@@ -538,12 +542,25 @@ if (typeof exports !== 'undefined') {exports.searchIndex = searchIndex};
                     let mut buf = Buffer::html();
                     cx.id_map = Default::default();
                     cx.deref_id_map = Default::default();
+                    let target_did = impl_
+                        .inner_impl()
+                        .trait_
+                        .as_ref()
+                        .map(|trait_| trait_.def_id())
+                        .or_else(|| impl_.inner_impl().for_.def_id(cache));
+                    let provided_methods;
+                    let assoc_link = if let Some(target_did) = target_did {
+                        provided_methods = impl_.inner_impl().provided_trait_methods(cx.tcx());
+                        AssocItemLink::GotoSource(ItemId::DefId(target_did), &provided_methods)
+                    } else {
+                        AssocItemLink::Anchor(None)
+                    };
                     super::render_impl(
                         &mut buf,
                         cx,
                         *impl_,
                         &type_alias_item,
-                        AssocItemLink::Anchor(None),
+                        assoc_link,
                         RenderMode::Normal,
                         None,
                         &[],
diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index 6f0bcb8e6d0..7c052606aba 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -680,12 +680,14 @@ function preLoadCss(cssUrl) {
 
         let implementations = document.getElementById("implementations-list");
         let trait_implementations = document.getElementById("trait-implementations-list");
+        let trait_implementations_header = document.getElementById("trait-implementations");
 
         // We want to include the current type alias's impls, and no others.
         const script = document.querySelector("script[data-self-path]");
         const selfPath = script ? script.getAttribute("data-self-path") : null;
 
         // These sidebar blocks need filled in, too.
+        const mainContent = document.querySelector("#main-content");
         const sidebarSection = document.querySelector(".sidebar section");
         let methods = document.querySelector(".sidebar .block.method");
         let associatedTypes = document.querySelector(".sidebar .block.associatedtype");
@@ -719,18 +721,18 @@ function preLoadCss(cssUrl) {
                     const h = document.createElement("h3");
                     h.appendChild(link);
                     trait_implementations = outputList;
+                    trait_implementations_header = outputListHeader;
                     sidebarSection.appendChild(h);
                     sidebarTraitList = document.createElement("ul");
                     sidebarTraitList.className = "block trait-implementation";
                     sidebarSection.appendChild(sidebarTraitList);
-                    const mainContent = document.querySelector("#main-content");
                     mainContent.appendChild(outputListHeader);
                     mainContent.appendChild(outputList);
                 } else {
                     implementations = outputList;
                     if (trait_implementations) {
-                        document.insertBefore(outputListHeader, trait_implementations);
-                        document.insertBefore(outputList, trait_implementations);
+                        mainContent.insertBefore(outputListHeader, trait_implementations_header);
+                        mainContent.insertBefore(outputList, trait_implementations_header);
                     } else {
                         const mainContent = document.querySelector("#main-content");
                         mainContent.appendChild(outputListHeader);
@@ -762,7 +764,14 @@ function preLoadCss(cssUrl) {
                     }
                 }
                 if (i !== 0) {
+                    const oldHref = `#${el.id}`;
+                    const newHref = `#${el.id}-${i}`;
                     el.id = `${el.id}-${i}`;
+                    onEachLazy(template.content.querySelectorAll("a[href]"), link => {
+                        if (link.getAttribute("href") === oldHref) {
+                            link.href = newHref;
+                        }
+                    });
                 }
                 idMap.set(el.id, i + 1);
             });
diff --git a/tests/rustdoc-gui/src/test_docs/lib.rs b/tests/rustdoc-gui/src/test_docs/lib.rs
index 5b6d5435b35..138a1b302fd 100644
--- a/tests/rustdoc-gui/src/test_docs/lib.rs
+++ b/tests/rustdoc-gui/src/test_docs/lib.rs
@@ -167,6 +167,26 @@ impl SomeOtherTypeWithMethodsAndInlining {
     pub fn some_other_method_directly(&self) {}
 }
 
+/// Another type alias, this time with methods.
+pub struct UnderlyingFooBarBaz;
+pub type SomeOtherTypeWithMethodsAndInliningAndTraits = UnderlyingFooBarBaz;
+
+impl AsRef<str> for UnderlyingFooBarBaz {
+    fn as_ref(&self) -> &str {
+        "hello"
+    }
+}
+
+impl UnderlyingFooBarBaz {
+    pub fn inherent_fn(&self) {}
+}
+
+impl AsRef<u8> for SomeOtherTypeWithMethodsAndInliningAndTraits {
+    fn as_ref(&self) -> &u8 {
+        b"hello"
+    }
+}
+
 pub mod huge_amount_of_consts {
     include!(concat!(env!("OUT_DIR"), "/huge_amount_of_consts.rs"));
 }
diff --git a/tests/rustdoc-gui/type-impls.goml b/tests/rustdoc-gui/type-impls.goml
index cc18b5de475..870a9cbe53f 100644
--- a/tests/rustdoc-gui/type-impls.goml
+++ b/tests/rustdoc-gui/type-impls.goml
@@ -24,11 +24,39 @@ assert-text: (".block.method li:nth-child(2)", 'some_other_method_directly')
 assert-text: (".block.method li:nth-child(3)", 'warning1')
 assert-text: (".block.method li:nth-child(4)", 'warning2')
 
+// Now try trait implementation merging and duplicate renumbering
+go-to: "file://" + |DOC_PATH| + "/test_docs/type.SomeOtherTypeWithMethodsAndInliningAndTraits.html"
+
+// method directly on type alias
+assert: "//*[@id='method.as_ref']"
+assert-count: ("//*[@id='method.as_ref']", 1)
+// method on underlying type
+assert: "//*[@id='method.as_ref-1']"
+
+// sidebar items
+assert-count: (
+    "//*[@class='sidebar-elems']//h3/a[@href='#trait-implementations']",
+    1
+)
+assert-text: ("//*[@class='sidebar-elems']//li/a[@href='#impl-AsRef%3Cstr%3E-for-UnderlyingFooBarBaz']", "AsRef<str>")
+assert-text: (
+    "//*[@class='sidebar-elems']//li/a[@href='#impl-AsRef%3Cu8%3E-for-UnderlyingFooBarBaz']",
+    "AsRef<u8>"
+)
+assert-count: ("#trait-implementations-list", 1)
+assert-count: ("#trait-implementations-list > details", 2)
+// Both links point at the underlying trait
+store-property: ("//*[@id='method.as_ref']//a[@class='fn']", {"href": href})
+assert-property: ("//*[@id='method.as_ref-1']//a[@class='fn']", {"href": |href|})
+// Both links have a self-anchor
+assert: "//*[@id='method.as_ref']//a[@class='anchor'][@href='#method.as_ref']"
+assert: "//*[@id='method.as_ref-1']//a[@class='anchor'][@href='#method.as_ref-1']"
+
 ///////////////////////////////////////////////////////////////////////////
 // Now, if JavaScript is disabled, only the first method will be present //
 ///////////////////////////////////////////////////////////////////////////
 javascript: false
-reload:
+go-to: "file://" + |DOC_PATH| + "/test_docs/type.SomeOtherTypeWithMethodsAndInlining.html"
 
 // method directly on type alias
 wait-for: "//*[@id='method.some_other_method_directly']"
@@ -37,3 +65,22 @@ wait-for: "//*[@id='method.some_other_method_directly']"
 assert-false: "//*[@id='method.must_use']"
 assert-false: "//*[@id='method.warning1']"
 assert-false: "//*[@id='method.warning2']"
+
+// Now try trait implementation merging and duplicate renumbering
+go-to: "file://" + |DOC_PATH| + "/test_docs/type.SomeOtherTypeWithMethodsAndInliningAndTraits.html"
+
+// methods directly on type alias
+assert: "//*[@id='method.as_ref']"
+assert-count: ("//*[@id='method.as_ref']", 1)
+// method on target type
+assert-false: "//*[@id='method.as_ref-1']"
+
+// sidebar items
+assert-count: (
+    "//*[@class='sidebar-elems']//h3/a[@href='#trait-implementations']",
+    1
+)
+assert-false: "//a[@href='#impl-AsRef%3Cstr%3E-for-UnderlyingFooBarBaz']"
+assert: "//a[@href='#impl-AsRef%3Cu8%3E-for-UnderlyingFooBarBaz']"
+assert-count: ("#trait-implementations-list", 1)
+assert-count: ("#trait-implementations-list > details", 1)
diff --git a/tests/rustdoc/type-alias/deref-32077.rs b/tests/rustdoc/type-alias/deref-32077.rs
index 740ed4cec70..186ebb1a632 100644
--- a/tests/rustdoc/type-alias/deref-32077.rs
+++ b/tests/rustdoc/type-alias/deref-32077.rs
@@ -22,7 +22,7 @@ impl Bar for GenericStruct<u32> {}
 // We check that "Aliased type" is also present as a title in the sidebar.
 // @has - '//*[@class="sidebar-elems"]//h3/a[@href="#aliased-type"]' 'Aliased type'
 // We check that we have the implementation of the type alias itself.
-// @has - '//*[@id="impl-TypedefStruct"]/h3' 'impl TypedefStruct'
+// @has - '//*[@id="impl-GenericStruct%3Cu8%3E"]/h3' 'impl TypedefStruct'
 // @has - '//*[@id="method.on_alias"]/h4' 'pub fn on_alias()'
 // This trait implementation doesn't match the type alias parameters so shouldn't appear in docs.
 // @!has - '//h3' 'impl Bar for GenericStruct<u32> {}'