only store locations in extern_locations

src/librustdoc/clean/types.rs

@@ -106,38 +106,39 @@ fn def_id(&self) -> DefId {
     crate fn location(
         &self,
         extern_url: Option<&str>,
-        ast_attrs: &[ast::Attribute],
         dst: &std::path::Path,
         tcx: TyCtxt<'_>,
     ) -> ExternalLocation {
         use ExternalLocation::*;
+
+        fn to_remote(url: impl ToString) -> ExternalLocation {
+            let mut url = url.to_string();
+            if !url.ends_with('/') {
+                url.push('/');
+            }
+            Remote(url)
+        }
+
         // See if there's documentation generated into the local directory
+        // WARNING: since rustdoc creates these directories as it generates documentation, this check is only accurate before rendering starts.
+        // Make sure to call `location()` by that time.
         let local_location = dst.join(&*self.name(tcx).as_str());
         if local_location.is_dir() {
             return Local;
         }
 
         if let Some(url) = extern_url {
-            let mut url = url.to_string();
-            if !url.ends_with('/') {
-                url.push('/');
-            }
-            return Remote(url);
+            return to_remote(url);
         }
 
         // Failing that, see if there's an attribute specifying where to find this
         // external crate
-        ast_attrs
+        let did = DefId { krate: self.crate_num, index: CRATE_DEF_INDEX };
+        tcx.get_attrs(did)
             .lists(sym::doc)
             .filter(|a| a.has_name(sym::html_root_url))
             .filter_map(|a| a.value_str())
-            .map(|url| {
-                let mut url = url.to_string();
-                if !url.ends_with('/') {
-                    url.push('/')
-                }
-                Remote(url)
-            })
+            .map(to_remote)
             .next()
             .unwrap_or(Unknown) // Well, at least we tried.
     }
@@ -433,7 +434,7 @@ pub fn from_def_id_and_attrs_and_parts(
                         let relative_to = &cx.current;
                         if let Some(ref fragment) = *fragment {
                             let url = match cx.cache().extern_locations.get(&self.def_id.krate) {
-                                Some(&(_, _, ExternalLocation::Local)) => {
+                                Some(ExternalLocation::Local) => {
                                     if relative_to[0] == "std" {
                                         let depth = relative_to.len() - 1;
                                         "../".repeat(depth)
@@ -442,10 +443,10 @@ pub fn from_def_id_and_attrs_and_parts(
                                         format!("{}std/", "../".repeat(depth))
                                     }
                                 }
-                                Some(&(_, _, ExternalLocation::Remote(ref s))) => {
+                                Some(ExternalLocation::Remote(ref s)) => {
                                     format!("{}/std/", s.trim_end_matches('/'))
                                 }
-                                Some(&(_, _, ExternalLocation::Unknown)) | None => format!(
+                                Some(ExternalLocation::Unknown) | None => format!(
                                     "https://doc.rust-lang.org/{}/std/",
                                     crate::doc_rust_lang_org_channel(),
                                 ),

src/librustdoc/formats/cache.rs

 use std::collections::BTreeMap;
 use std::mem;
-use std::path::{Path, PathBuf};
+use std::path::Path;
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX};
 use rustc_middle::middle::privacy::AccessLevels;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::symbol::sym;
-use rustc_span::Symbol;
 
 use crate::clean::{self, GetDefId};
 use crate::fold::DocFolder;
@@ -71,7 +70,7 @@
     crate implementors: FxHashMap<DefId, Vec<Impl>>,
 
     /// Cache of where external crate documentation can be found.
-    crate extern_locations: FxHashMap<CrateNum, (Symbol, PathBuf, ExternalLocation)>,
+    crate extern_locations: FxHashMap<CrateNum, ExternalLocation>,
 
     /// Cache of where documentation for primitives can be found.
     crate primitive_locations: FxHashMap<clean::PrimitiveType, DefId>,
@@ -157,10 +156,7 @@ impl Cache {
             let name = e.name(tcx);
             let extern_url = extern_html_root_urls.get(&*name.as_str()).map(|u| &**u);
             let did = DefId { krate: n, index: CRATE_DEF_INDEX };
-            self.extern_locations.insert(
-                n,
-                (name, e.src_root(tcx), e.location(extern_url, tcx.get_attrs(did), &dst, tcx)),
-            );
+            self.extern_locations.insert(n, e.location(extern_url, &dst, tcx));
             self.external_paths.insert(did, (vec![name.to_string()], ItemType::Module));
         }
 

src/librustdoc/html/format.rs

@@ -16,7 +16,7 @@
 use rustc_span::def_id::{DefId, CRATE_DEF_INDEX};
 use rustc_target::spec::abi::Abi;
 
-use crate::clean::{self, utils::find_nearest_parent_module, PrimitiveType};
+use crate::clean::{self, utils::find_nearest_parent_module, ExternalCrate, PrimitiveType};
 use crate::formats::item_type::ItemType;
 use crate::html::escape::Escape;
 use crate::html::render::cache::ExternalLocation;
@@ -461,14 +461,14 @@ fn to_module_fqp(shortty: ItemType, fqp: &[String]) -> &[String] {
                 fqp,
                 shortty,
                 match cache.extern_locations[&did.krate] {
-                    (.., ExternalLocation::Remote(ref s)) => {
+                    ExternalLocation::Remote(ref s) => {
                         let s = s.trim_end_matches('/');
                         let mut s = vec![&s[..]];
                         s.extend(module_fqp[..].iter().map(String::as_str));
                         s
                     }
-                    (.., ExternalLocation::Local) => href_relative_parts(module_fqp, relative_to),
-                    (.., ExternalLocation::Unknown) => return None,
+                    ExternalLocation::Local => href_relative_parts(module_fqp, relative_to),
+                    ExternalLocation::Unknown => return None,
                 },
             )
         }
@@ -574,12 +574,14 @@ fn primitive_link(
             Some(&def_id) => {
                 let cname_str;
                 let loc = match m.extern_locations[&def_id.krate] {
-                    (ref cname, _, ExternalLocation::Remote(ref s)) => {
-                        cname_str = cname.as_str();
+                    ExternalLocation::Remote(ref s) => {
+                        cname_str =
+                            ExternalCrate { crate_num: def_id.krate }.name(cx.tcx()).as_str();
                         Some(vec![s.trim_end_matches('/'), &cname_str[..]])
                     }
-                    (ref cname, _, ExternalLocation::Local) => {
-                        cname_str = cname.as_str();
+                    ExternalLocation::Local => {
+                        cname_str =
+                            ExternalCrate { crate_num: def_id.krate }.name(cx.tcx()).as_str();
                         Some(if cx.current.first().map(|x| &x[..]) == Some(&cname_str[..]) {
                             iter::repeat("..").take(cx.current.len() - 1).collect()
                         } else {
@@ -587,7 +589,7 @@ fn primitive_link(
                             iter::repeat("..").take(cx.current.len()).chain(cname).collect()
                         })
                     }
-                    (.., ExternalLocation::Unknown) => None,
+                    ExternalLocation::Unknown => None,
                 };
                 if let Some(loc) = loc {
                     write!(

src/librustdoc/html/render/context.rs

@@ -18,7 +18,7 @@
 use super::write_shared::write_shared;
 use super::{print_sidebar, settings, AllTypes, NameDoc, StylePath, BASIC_KEYWORDS};
 
-use crate::clean;
+use crate::clean::{self, ExternalCrate};
 use crate::config::RenderOptions;
 use crate::docfs::{DocFS, PathError};
 use crate::error::Error;
@@ -304,12 +304,16 @@ pub(super) fn src_href(&self, item: &clean::Item) -> Option<String> {
             }
         } else {
             let (krate, src_root) = match *self.cache.extern_locations.get(&cnum)? {
-                (name, ref src, ExternalLocation::Local) => (name, src),
-                (name, ref src, ExternalLocation::Remote(ref s)) => {
+                ExternalLocation::Local => {
+                    let e = ExternalCrate { crate_num: cnum };
+                    (e.name(self.tcx()), e.src_root(self.tcx()))
+                }
+                ExternalLocation::Remote(ref s) => {
                     root = s.to_string();
-                    (name, src)
+                    let e = ExternalCrate { crate_num: cnum };
+                    (e.name(self.tcx()), e.src_root(self.tcx()))
                 }
-                (_, _, ExternalLocation::Unknown) => return None,
+                ExternalLocation::Unknown => return None,
             };
 
             sources::clean_path(&src_root, file, false, |component| {

src/librustdoc/json/mod.rs

@@ -17,7 +17,7 @@
 
 use rustdoc_json_types as types;
 
-use crate::clean;
+use crate::clean::{self, ExternalCrate};
 use crate::config::RenderOptions;
 use crate::error::Error;
 use crate::formats::cache::Cache;
@@ -218,12 +218,13 @@ fn after_krate(&mut self) -> Result<(), Error> {
                 .cache
                 .extern_locations
                 .iter()
-                .map(|(k, v)| {
+                .map(|(crate_num, external_location)| {
+                    let e = ExternalCrate { crate_num: *crate_num };
                     (
-                        k.as_u32(),
+                        crate_num.as_u32(),
                         types::ExternalCrate {
-                            name: v.0.to_string(),
-                            html_root_url: match &v.2 {
+                            name: e.name(self.tcx).to_string(),
+                            html_root_url: match external_location {
                                 ExternalLocation::Remote(s) => Some(s.clone()),
                                 _ => None,
                             },