Use relative path for local links to primitives

src/librustdoc/clean/types.rs

@@ -628,6 +628,7 @@ impl Attributes {
     /// Cache must be populated before call
     pub fn links(&self, krate: &CrateNum) -> Vec<(String, String)> {
         use crate::html::format::href;
+        use crate::html::render::CURRENT_DEPTH;
 
         self.links
             .iter()
@@ -648,13 +649,16 @@ impl Attributes {
                         if let Some(ref fragment) = *fragment {
                             let cache = cache();
                             let url = match cache.extern_locations.get(krate) {
-                                Some(&(_, ref src, ExternalLocation::Local)) => {
-                                    src.to_str().expect("invalid file path")
-                                }
-                                Some(&(_, _, ExternalLocation::Remote(ref s))) => s,
-                                Some(&(_, _, ExternalLocation::Unknown)) | None => {
-                                    "https://doc.rust-lang.org/nightly"
+                                Some(&(ref krate_name, _, ExternalLocation::Local))
+                                    if krate_name == "core" =>
+                                {
+                                    let depth = CURRENT_DEPTH.with(|l| l.get());
+                                    "../".repeat(depth)
                                 }
+                                Some(&(_, _, ExternalLocation::Remote(ref s))) => s.to_string(),
+                                Some(&(_, _, ExternalLocation::Local))
+                                | Some(&(_, _, ExternalLocation::Unknown))
+                                | None => String::from("https://doc.rust-lang.org/nightly"),
                             };
                             // This is a primitive so the url is done "by hand".
                             let tail = fragment.find('#').unwrap_or_else(|| fragment.len());

src/test/rustdoc/auxiliary/my-core.rs

@@ -0,0 +1,18 @@
+#![feature(no_core, lang_items)]
+#![no_core]
+
+#[lang = "char"]
+impl char {
+    pub fn len_utf8(self) -> usize {
+        42
+    }
+}
+
+#[lang = "sized"]
+pub trait Sized {}
+
+#[lang = "clone"]
+pub trait Clone: Sized {}
+
+#[lang = "copy"]
+pub trait Copy: Clone {}

src/test/rustdoc/intra-link-prim-methods-external-core.rs

@@ -0,0 +1,16 @@
+// aux-build:my-core.rs
+// build-aux-docs
+// ignore-cross-compile
+// ignore-tidy-linelength
+
+#![deny(intra_doc_link_resolution_failure)]
+#![feature(no_core, lang_items)]
+#![no_core]
+
+// @has intra_link_prim_methods_external_core/index.html
+// @has - '//*[@id="main"]//a[@href="https://doc.rust-lang.org/nightly/std/primitive.char.html"]' 'char'
+// @has - '//*[@id="main"]//a[@href="https://doc.rust-lang.org/nightly/std/primitive.char.html#method.len_utf8"]' 'char::len_utf8'
+
+//! A [`char`] and its [`char::len_utf8`].
+
+extern crate my_core;

src/test/rustdoc/intra-link-prim-methods-local.rs

@@ -0,0 +1,27 @@
+#![deny(intra_doc_link_resolution_failure)]
+#![feature(no_core, lang_items)]
+#![no_core]
+
+// ignore-tidy-linelength
+
+// @has intra_link_prim_methods_local/index.html
+// @has - '//*[@id="main"]//a[@href="https://doc.rust-lang.org/nightly/std/primitive.char.html"]' 'char'
+// @has - '//*[@id="main"]//a[@href="https://doc.rust-lang.org/nightly/std/primitive.char.html#method.len_utf8"]' 'char::len_utf8'
+
+//! A [`char`] and its [`char::len_utf8`].
+
+#[lang = "char"]
+impl char {
+    pub fn len_utf8(self) -> usize {
+        42
+    }
+}
+
+#[lang = "sized"]
+pub trait Sized {}
+
+#[lang = "clone"]
+pub trait Clone: Sized {}
+
+#[lang = "copy"]
+pub trait Copy: Clone {}

src/test/rustdoc/intra-link-prim-methods.rs

@@ -1,3 +1,9 @@
 #![deny(intra_doc_link_resolution_failure)]
 
+// ignore-tidy-linelength
+
+// @has intra_link_prim_methods/index.html
+// @has - '//*[@id="main"]//a[@href="https://doc.rust-lang.org/nightly/std/primitive.char.html"]' 'char'
+// @has - '//*[@id="main"]//a[@href="https://doc.rust-lang.org/nightly/std/primitive.char.html#method.len_utf8"]' 'char::len_utf8'
+
 //! A [`char`] and its [`char::len_utf8`].