rustdoc: link consistently to stable/beta in diagnostic messages

src/librustdoc/clean/utils.rs

@@ -544,7 +544,8 @@ fn print_const_with_custom_print_scalar(tcx: TyCtxt<'_>, ct: &'tcx ty::Const<'tc
     })
 }
 
-/// A link to `doc.rust-lang.org` that includes the channel name.
+/// A link to `doc.rust-lang.org` that includes the channel name. Use this instead of manual links
+/// so that the channel is consistent.
 ///
 /// Set by `bootstrap::Builder::doc_rust_lang_org_channel` in order to keep tests passing on beta/stable.
 crate const DOC_RUST_LANG_ORG_CHANNEL: &'static str = env!("DOC_RUST_LANG_ORG_CHANNEL");

src/librustdoc/core.rs

@@ -399,15 +399,18 @@ impl<'tcx> DocContext<'tcx> {
     let mut krate = tcx.sess.time("clean_crate", || clean::krate(&mut ctxt));
 
     if krate.module.doc_value().map(|d| d.is_empty()).unwrap_or(true) {
-        let help = "The following guide may be of use:\n\
-                https://doc.rust-lang.org/nightly/rustdoc/how-to-write-documentation.html";
+        let help = format!(
+            "The following guide may be of use:\n\
+            {}/rustdoc/how-to-write-documentation.html",
+            crate::DOC_RUST_LANG_ORG_CHANNEL
+        );
         tcx.struct_lint_node(
             crate::lint::MISSING_CRATE_LEVEL_DOCS,
             DocContext::as_local_hir_id(tcx, krate.module.def_id).unwrap(),
             |lint| {
                 let mut diag =
                     lint.build("no documentation found for this crate's top-level module");
-                diag.help(help);
+                diag.help(&help);
                 diag.emit();
             },
         );

src/librustdoc/lib.rs

@@ -605,7 +605,10 @@ fn usage(argv0: &str) {
     }
     println!("{}", options.usage(&format!("{} [options] <input>", argv0)));
     println!("    @path               Read newline separated options from `path`\n");
-    println!("More information available at https://doc.rust-lang.org/rustdoc/what-is-rustdoc.html")
+    println!(
+        "More information available at {}/rustdoc/what-is-rustdoc.html",
+        DOC_RUST_LANG_ORG_CHANNEL
+    );
 }
 
 /// A result type used by several functions under `main()`.

src/librustdoc/passes/collect_intra_doc_links.rs

@@ -1999,8 +1999,11 @@ fn disambiguator_error(
 ) {
     diag_info.link_range = disambiguator_range;
     report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, msg, &diag_info, |diag, _sp| {
-        let msg = "see https://doc.rust-lang.org/nightly/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators";
-        diag.note(msg);
+        let msg = format!(
+            "see {}/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators",
+            crate::DOC_RUST_LANG_ORG_CHANNEL
+        );
+        diag.note(&msg);
     });
 }