rustdoc: few small cleanups

src/librustdoc/formats/cache.rs

@@ -242,7 +242,7 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
  }
 
  // Index this method for searching later on.
- if let Some(ref s) = item.name.or_else(|| {
+ if let Some(s) = item.name.or_else(|| {
  if item.is_stripped() {
  None
  } else if let clean::ImportItem(ref i) = *item.kind &&
@@ -317,14 +317,15 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
  short_markdown_summary(x.as_str(), &item.link_names(self.cache))
  });
  let ty = item.type_();
- let name = s.to_string();
- if ty != ItemType::StructField || u16::from_str_radix(&name, 10).is_err() {
+ if ty != ItemType::StructField
+ || u16::from_str_radix(s.as_str(), 10).is_err()
+ {
  // In case this is a field from a tuple struct, we don't add it into
  // the search index because its name is something like "0", which is
  // not useful for rustdoc search.
  self.cache.search_index.push(IndexItem {
  ty,
- name,
+ name: s,
  path: join_with_double_colon(path),
  desc,
  parent,

src/librustdoc/html/format.rs

@@ -569,7 +569,7 @@ fn generate_macro_def_id_path(
  root_path: Option<&str>,
 ) -> Result<(String, ItemType, Vec<Symbol>), HrefError> {
  let tcx = cx.shared.tcx;
- let crate_name = tcx.crate_name(def_id.krate).to_string();
+ let crate_name = tcx.crate_name(def_id.krate);
  let cache = cx.cache();
 
  let fqp: Vec<Symbol> = tcx
@@ -584,7 +584,7 @@ fn generate_macro_def_id_path(
  }
  })
  .collect();
- let mut relative = fqp.iter().map(|elem| elem.to_string());
+ let mut relative = fqp.iter().copied();
  let cstore = CStore::from_tcx(tcx);
  // We need this to prevent a `panic` when this function is used from intra doc links...
  if !cstore.has_crate_data(def_id.krate) {
@@ -602,9 +602,9 @@ fn generate_macro_def_id_path(
  };
 
  let mut path = if is_macro_2 {
- once(crate_name.clone()).chain(relative).collect()
+ once(crate_name).chain(relative).collect()
  } else {
- vec![crate_name.clone(), relative.next_back().unwrap()]
+ vec![crate_name, relative.next_back().unwrap()]
  };
  if path.len() < 2 {
  // The minimum we can have is the crate name followed by the macro name. If shorter, then
@@ -614,17 +614,22 @@ fn generate_macro_def_id_path(
  }
 
  if let Some(last) = path.last_mut() {
- *last = format!("macro.{}.html", last);
+ *last = Symbol::intern(&format!("macro.{}.html", last.as_str()));
  }
 
  let url = match cache.extern_locations[&def_id.krate] {
  ExternalLocation::Remote(ref s) => {
  // `ExternalLocation::Remote` always end with a `/`.
- format!("{}{}", s, path.join("/"))
+ format!("{}{}", s, path.iter().map(|p| p.as_str()).join("/"))
  }
  ExternalLocation::Local => {
  // `root_path` always end with a `/`.
- format!("{}{}/{}", root_path.unwrap_or(""), crate_name, path.join("/"))
+ format!(
+ "{}{}/{}",
+ root_path.unwrap_or(""),
+ crate_name,
+ path.iter().map(|p| p.as_str()).join("/")
+ )
  }
  ExternalLocation::Unknown => {
  debug!("crate {} not in cache when linkifying macros", crate_name);
@@ -1050,7 +1055,7 @@ fn fmt_type<'cx>(
  _ => String::new(),
  };
  let m = mutability.print_with_space();
- let amp = if f.alternate() { "&".to_string() } else { "&amp;".to_string() };
+ let amp = if f.alternate() { "&" } else { "&amp;" };
  match **ty {
  clean::DynTrait(ref bounds, ref trait_lt)
  if bounds.len() > 1 || trait_lt.is_some() =>

src/librustdoc/html/markdown.rs

@@ -30,7 +30,7 @@ use rustc_hir::def_id::DefId;
 use rustc_hir::HirId;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::edition::Edition;
-use rustc_span::Span;
+use rustc_span::{Span, Symbol};
 
 use once_cell::sync::Lazy;
 use std::borrow::Cow;
@@ -198,7 +198,7 @@ fn slugify(c: char) -> Option<char> {
 
 #[derive(Clone, Debug)]
 pub struct Playground {
- pub crate_name: Option<String>,
+ pub crate_name: Option<Symbol>,
  pub url: String,
 }
 
@@ -290,7 +290,7 @@ impl<'a, I: Iterator<Item = Event<'a>>> Iterator for CodeBlocks<'_, 'a, I> {
  .map(|l| map_line(l).for_code())
  .intersperse("\n".into())
  .collect::<String>();
- let krate = krate.as_ref().map(|s| &**s);
+ let krate = krate.as_ref().map(|s| s.as_str());
  let (test, _, _) =
  doctest::make_test(&test, krate, false, &Default::default(), edition, None);
  let channel = if test.contains("#![feature(") { "&amp;version=nightly" } else { "" };

src/librustdoc/html/render/context.rs

@@ -464,8 +464,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
  // If user passed in `--playground-url` arg, we fill in crate name here
  let mut playground = None;
  if let Some(url) = playground_url {
- playground =
- Some(markdown::Playground { crate_name: Some(krate.name(tcx).to_string()), url });
+ playground = Some(markdown::Playground { crate_name: Some(krate.name(tcx)), url });
  }
  let mut layout = layout::Layout {
  logo: String::new(),
@@ -491,7 +490,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
  }
  (sym::html_playground_url, Some(s)) => {
  playground = Some(markdown::Playground {
- crate_name: Some(krate.name(tcx).to_string()),
+ crate_name: Some(krate.name(tcx)),
  url: s.to_string(),
  });
  }

src/librustdoc/html/render/mod.rs

@@ -100,7 +100,7 @@ pub(crate) fn ensure_trailing_slash(v: &str) -> impl fmt::Display + '_ {
 #[derive(Debug)]
 pub(crate) struct IndexItem {
  pub(crate) ty: ItemType,
- pub(crate) name: String,
+ pub(crate) name: Symbol,
  pub(crate) path: String,
  pub(crate) desc: String,
  pub(crate) parent: Option<DefId>,
@@ -2769,8 +2769,8 @@ fn collect_paths_for_type(first_ty: clean::Type, cache: &Cache) -> Vec<String> {
  let mut work = VecDeque::new();
 
  let mut process_path = |did: DefId| {
- let get_extern = || cache.external_paths.get(&did).map(|s| s.0.clone());
- let fqp = cache.exact_paths.get(&did).cloned().or_else(get_extern);
+ let get_extern = || cache.external_paths.get(&did).map(|s| &s.0);
+ let fqp = cache.exact_paths.get(&did).or_else(get_extern);
 
  if let Some(path) = fqp {
  out.push(join_with_double_colon(&path));

src/librustdoc/html/render/print_item.rs

@@ -1027,8 +1027,8 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
  .chain(std::iter::once("implementors"))
  .collect();
  if let Some(did) = it.item_id.as_def_id() &&
- let get_extern = { || cache.external_paths.get(&did).map(|s| s.0.clone()) } &&
- let Some(fqp) = cache.exact_paths.get(&did).cloned().or_else(get_extern) {
+ let get_extern = { || cache.external_paths.get(&did).map(|s| &s.0) } &&
+ let Some(fqp) = cache.exact_paths.get(&did).or_else(get_extern) {
  js_src_path.extend(fqp[..fqp.len() - 1].iter().copied());
  js_src_path.push_fmt(format_args!("{}.{}.js", it.type_(), fqp.last().unwrap()));
  } else {

src/librustdoc/html/render/search_index.rs

@@ -35,7 +35,7 @@ pub(crate) fn build_index<'tcx>(
  .map_or_else(String::new, |s| short_markdown_summary(&s, &item.link_names(cache)));
  cache.search_index.push(IndexItem {
  ty: item.type_(),
- name: item.name.unwrap().to_string(),
+ name: item.name.unwrap(),
  path: join_with_double_colon(&fqp[..fqp.len() - 1]),
  desc,
  parent: Some(parent),
@@ -58,8 +58,8 @@ pub(crate) fn build_index<'tcx>(
  // Sort search index items. This improves the compressibility of the search index.
  cache.search_index.sort_unstable_by(|k1, k2| {
  // `sort_unstable_by_key` produces lifetime errors
- let k1 = (&k1.path, &k1.name, &k1.ty, &k1.parent);
- let k2 = (&k2.path, &k2.name, &k2.ty, &k2.parent);
+ let k1 = (&k1.path, k1.name.as_str(), &k1.ty, &k1.parent);
+ let k2 = (&k2.path, k2.name.as_str(), &k2.ty, &k2.parent);
  std::cmp::Ord::cmp(&k1, &k2)
  });
 
@@ -240,7 +240,7 @@ pub(crate) fn build_index<'tcx>(
  )?;
  crate_data.serialize_field(
  "n",
- &self.items.iter().map(|item| &item.name).collect::<Vec<_>>(),
+ &self.items.iter().map(|item| item.name.as_str()).collect::<Vec<_>>(),
  )?;
  crate_data.serialize_field(
  "q",
@@ -299,7 +299,7 @@ pub(crate) fn build_index<'tcx>(
  )?;
  crate_data.serialize_field(
  "p",
- &self.paths.iter().map(|(it, s)| (it, s.to_string())).collect::<Vec<_>>(),
+ &self.paths.iter().map(|(it, s)| (it, s.as_str())).collect::<Vec<_>>(),
  )?;
  if has_aliases {
  crate_data.serialize_field("a", &self.aliases)?;