Improve doc alias discovery

Author: GuillaumeGomez

src/librustdoc/html/render.rs

@@ -278,7 +278,7 @@ pub struct RenderInfo {
 /// Struct representing one entry in the JS search index. These are all emitted
 /// by hand to a large JS file at the end of cache-creation.
 #[derive(Debug)]
-struct IndexItem {
+pub struct IndexItem {
     ty: ItemType,
     name: String,
     path: String,
@@ -293,7 +293,12 @@ impl Serialize for IndexItem {
     where
         S: Serializer,
     {
-        assert_eq!(self.parent.is_some(), self.parent_idx.is_some());
+        assert_eq!(
+            self.parent.is_some(),
+            self.parent_idx.is_some(),
+            "`{}` is missing idx",
+            self.name
+        );
 
         (self.ty, &self.name, &self.path, &self.desc, self.parent_idx, &self.search_type)
             .serialize(serializer)
@@ -836,7 +841,7 @@ themePicker.onblur = handleThemeButtonsBlur;
     {
         let (mut all_aliases, _) = try_err!(collect(&dst, &krate.name, "ALIASES"), &dst);
         let mut output = String::with_capacity(100);
-        for (alias, items) in &cx.cache.aliases {
+        for (alias, items) in cx.cache.get_aliases() {
             if items.is_empty() {
                 continue;
             }

src/librustdoc/html/render/cache.rs

@@ -120,7 +120,7 @@ crate struct Cache {
 
     /// Aliases added through `#[doc(alias = "...")]`. Since a few items can have the same alias,
     /// we need the alias element to have an array of items.
-    pub(super) aliases: FxHashMap<String, Vec<IndexItem>>,
+    pub(super) aliases: FxHashMap<String, Vec<usize>>,
 }
 
 impl Cache {
@@ -311,7 +311,7 @@ impl DocFolder for Cache {
             };
 
             match parent {
-                (parent, Some(path)) if is_inherent_impl_item || (!self.stripped_mod) => {
+                (parent, Some(path)) if is_inherent_impl_item || !self.stripped_mod => {
                     debug_assert!(!item.is_stripped());
 
                     // A crate has a module at its root, containing all items,
@@ -327,6 +327,21 @@ impl DocFolder for Cache {
                             parent_idx: None,
                             search_type: get_index_search_type(&item),
                         });
+
+                        for alias in item
+                            .attrs
+                            .lists(sym::doc)
+                            .filter(|a| a.check_name(sym::alias))
+                            .filter_map(|a| a.value_str().map(|s| s.to_string().replace("\"", "")))
+                            .filter(|v| !v.is_empty())
+                            .collect::<FxHashSet<_>>()
+                            .into_iter()
+                        {
+                            self.aliases
+                                .entry(alias.to_lowercase())
+                                .or_insert(Vec::with_capacity(1))
+                                .push(self.search_index.len() - 1);
+                        }
                     }
                 }
                 (Some(parent), None) if is_inherent_impl_item => {
@@ -363,6 +378,9 @@ impl DocFolder for Cache {
             | clean::MacroItem(..)
             | clean::ProcMacroItem(..)
             | clean::VariantItem(..)
+            | clean::StructFieldItem(..)
+            | clean::TyMethodItem(..)
+            | clean::MethodItem(..)
                 if !self.stripped_mod =>
             {
                 // Re-exported items mean that the same id can show up twice
@@ -376,11 +394,8 @@ impl DocFolder for Cache {
                 {
                     self.paths.insert(item.def_id, (self.stack.clone(), item.type_()));
                 }
-                self.add_aliases(&item);
             }
-
             clean::PrimitiveItem(..) => {
-                self.add_aliases(&item);
                 self.paths.insert(item.def_id, (self.stack.clone(), item.type_()));
             }
 
@@ -489,36 +504,23 @@ impl DocFolder for Cache {
 }
 
 impl Cache {
-    fn add_aliases(&mut self, item: &clean::Item) {
-        if item.def_id.index == CRATE_DEF_INDEX {
-            return;
-        }
-        if let Some(ref item_name) = item.name {
-            let path = self
-                .paths
-                .get(&item.def_id)
-                .map(|p| p.0[..p.0.len() - 1].join("::"))
-                .unwrap_or("std".to_owned());
-            for alias in item
-                .attrs
-                .lists(sym::doc)
-                .filter(|a| a.check_name(sym::alias))
-                .filter_map(|a| a.value_str().map(|s| s.to_string().replace("\"", "")))
-                .filter(|v| !v.is_empty())
-                .collect::<FxHashSet<_>>()
-                .into_iter()
-            {
-                self.aliases.entry(alias).or_insert(Vec::with_capacity(1)).push(IndexItem {
-                    ty: item.type_(),
-                    name: item_name.to_string(),
-                    path: path.clone(),
-                    desc: shorten(plain_summary_line(item.doc_value())),
-                    parent: None,
-                    parent_idx: None,
-                    search_type: get_index_search_type(&item),
-                });
-            }
-        }
+    pub fn get_aliases<'a>(&'a self) -> FxHashMap<String, Vec<&'a IndexItem>> {
+        self.aliases
+            .iter()
+            .map(|(k, values)| {
+                (
+                    k.clone(),
+                    values
+                        .iter()
+                        .filter(|v| {
+                            let x = &self.search_index[**v];
+                            x.parent_idx.is_some() == x.parent.is_some()
+                        })
+                        .map(|v| &self.search_index[*v])
+                        .collect::<Vec<_>>(),
+                )
+            })
+            .collect()
     }
 }
 
@@ -567,7 +569,8 @@ fn build_index(krate: &clean::Crate, cache: &mut Cache) -> String {
     let mut crate_items = Vec::with_capacity(cache.search_index.len());
     let mut crate_paths = vec![];
 
-    let Cache { ref mut search_index, ref orphan_impl_items, ref paths, .. } = *cache;
+    let Cache { ref mut search_index, ref orphan_impl_items, ref paths, ref mut aliases, .. } =
+        *cache;
 
     // Attach all orphan items to the type's definition if the type
     // has since been learned.
@@ -582,6 +585,20 @@ fn build_index(krate: &clean::Crate, cache: &mut Cache) -> String {
                 parent_idx: None,
                 search_type: get_index_search_type(&item),
             });
+            for alias in item
+                .attrs
+                .lists(sym::doc)
+                .filter(|a| a.check_name(sym::alias))
+                .filter_map(|a| a.value_str().map(|s| s.to_string().replace("\"", "")))
+                .filter(|v| !v.is_empty())
+                .collect::<FxHashSet<_>>()
+                .into_iter()
+            {
+                aliases
+                    .entry(alias.to_lowercase())
+                    .or_insert(Vec::with_capacity(1))
+                    .push(search_index.len() - 1);
+            }
         }
     }