Avoid some unnecessary cloning.

Author: nnethercote

src/librustdoc/clean/types.rs

@@ -106,7 +106,7 @@ impl From<DefId> for ItemId {
 }
 
 /// The crate currently being documented.
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 pub(crate) struct Crate {
     pub(crate) module: Item,
     /// Only here so that they can be filtered through the rustdoc passes.

src/librustdoc/html/layout.rs

@@ -8,7 +8,6 @@ use super::static_files::{STATIC_FILES, StaticFiles};
 use crate::externalfiles::ExternalHtml;
 use crate::html::render::{StylePath, ensure_trailing_slash};
 
-#[derive(Clone)]
 pub(crate) struct Layout {
     pub(crate) logo: String,
     pub(crate) favicon: String,

src/librustdoc/html/markdown.rs

@@ -195,7 +195,7 @@ fn slugify(c: char) -> Option<char> {
     }
 }
 
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 pub struct Playground {
     pub crate_name: Option<Symbol>,
     pub url: String,

src/librustdoc/html/render/mod.rs

@@ -2530,7 +2530,7 @@ fn item_ty_to_section(ty: ItemType) -> ItemSection {
 /// types are re-exported, we don't use the corresponding
 /// entry from the js file, as inlining will have already
 /// picked up the impl
-fn collect_paths_for_type(first_ty: clean::Type, cache: &Cache) -> Vec<String> {
+fn collect_paths_for_type(first_ty: &clean::Type, cache: &Cache) -> Vec<String> {
     let mut out = Vec::new();
     let mut visited = FxHashSet::default();
     let mut work = VecDeque::new();
@@ -2547,7 +2547,7 @@ fn collect_paths_for_type(first_ty: clean::Type, cache: &Cache) -> Vec<String> {
     work.push_back(first_ty);
 
     while let Some(ty) = work.pop_front() {
-        if !visited.insert(ty.clone()) {
+        if !visited.insert(ty) {
             continue;
         }
 
@@ -2557,16 +2557,16 @@ fn collect_paths_for_type(first_ty: clean::Type, cache: &Cache) -> Vec<String> {
                 work.extend(tys.into_iter());
             }
             clean::Type::Slice(ty) => {
-                work.push_back(*ty);
+                work.push_back(ty);
             }
             clean::Type::Array(ty, _) => {
-                work.push_back(*ty);
+                work.push_back(ty);
             }
             clean::Type::RawPointer(_, ty) => {
-                work.push_back(*ty);
+                work.push_back(ty);
             }
             clean::Type::BorrowedRef { type_, .. } => {
-                work.push_back(*type_);
+                work.push_back(type_);
             }
             clean::Type::QPath(box clean::QPathData { self_type, trait_, .. }) => {
                 work.push_back(self_type);

src/librustdoc/html/render/print_item.rs

@@ -659,7 +659,7 @@ fn item_trait(cx: &Context<'_>, it: &clean::Item, t: &clean::Trait) -> impl fmt:
         let count_types = required_types.len() + provided_types.len();
         let count_consts = required_consts.len() + provided_consts.len();
         let count_methods = required_methods.len() + provided_methods.len();
-        let must_implement_one_of_functions = tcx.trait_def(t.def_id).must_implement_one_of.clone();
+        let must_implement_one_of_functions = &tcx.trait_def(t.def_id).must_implement_one_of;
 
         // Output the trait definition
         wrap_item(w, |mut w| {
@@ -1095,7 +1095,7 @@ fn item_trait(cx: &Context<'_>, it: &clean::Item, t: &clean::Trait) -> impl fmt:
                             it,
                             &implementor_dups,
                             &collect_paths_for_type(
-                                implementor.inner_impl().for_.clone(),
+                                &implementor.inner_impl().for_,
                                 &cx.shared.cache,
                             ),
                         )

src/librustdoc/html/render/write_shared.rs

@@ -760,7 +760,7 @@ impl TraitAliasPart {
                         Some(Implementor {
                             text: imp.inner_impl().print(false, cx).to_string(),
                             synthetic: imp.inner_impl().kind.is_auto(),
-                            types: collect_paths_for_type(imp.inner_impl().for_.clone(), cache),
+                            types: collect_paths_for_type(&imp.inner_impl().for_, cache),
                         })
                     }
                 })