rustdoc: when removing duplicate names, ignore #[doc(hidden)] items

Author: notriddle

src/librustdoc/clean/mod.rs

@@ -50,7 +50,7 @@ pub(crate) fn clean_doc_module<'tcx>(doc: &DocModule<'tcx>, cx: &mut DocContext<
     let mut inserted = FxHashSet::default();
     items.extend(doc.foreigns.iter().map(|(item, renamed)| {
         let item = clean_maybe_renamed_foreign_item(cx, item, *renamed);
-        if let Some(name) = item.name {
+        if let Some(name) = item.name && !item.attrs.lists(sym::doc).has_word(sym::hidden) {
             inserted.insert((item.type_(), name));
         }
         item
@@ -59,7 +59,14 @@ pub(crate) fn clean_doc_module<'tcx>(doc: &DocModule<'tcx>, cx: &mut DocContext<
         if !inserted.insert((ItemType::Module, x.name)) {
             return None;
         }
-        Some(clean_doc_module(x, cx))
+        let item = clean_doc_module(x, cx);
+        if item.attrs.lists(sym::doc).has_word(sym::hidden) {
+            // Hidden modules are stripped at a later stage.
+            // If a hidden module has the same name as a visible one, we want
+            // to keep both of them around.
+            inserted.remove(&(ItemType::Module, x.name));
+        }
+        Some(item)
     }));
 
     // Split up imports from all other items.
@@ -74,7 +81,7 @@ pub(crate) fn clean_doc_module<'tcx>(doc: &DocModule<'tcx>, cx: &mut DocContext<
         }
         let v = clean_maybe_renamed_item(cx, item, *renamed);
         for item in &v {
-            if let Some(name) = item.name {
+            if let Some(name) = item.name && !item.attrs.lists(sym::doc).has_word(sym::hidden) {
                 inserted.insert((item.type_(), name));
             }
         }