* Select the current channel as the default selected version.

* Improve bootstrap source code

Author: GuillaumeGomez

src/bootstrap/doc.rs

@@ -430,12 +430,11 @@ impl Step for Std {
         t!(fs::create_dir_all(&out));
         t!(fs::copy(builder.src.join("src/doc/rust.css"), out.join("rust.css")));
 
-        let content = fs::read_to_string(builder.src.join("src/doc/version-switcher.js")).unwrap();
-        fs::write(
+        let content = t!(fs::read_to_string(builder.src.join("src/doc/version-switcher.js")));
+        t!(fs::write(
             out.join("version-switcher.js"),
             content.replace("/* VERSION TO BE REPLACED */", &builder.version),
-        )
-        .unwrap();
+        ));
 
         let index_page = builder.src.join("src/doc/index.md").into_os_string();
         let switcher_script = builder.src.join("src/doc/switcher.inc").into_os_string();

src/doc/version-switcher.js

@@ -2,7 +2,7 @@ const CURRENT_VERSION = "/* VERSION TO BE REPLACED */";
 
 function checkIfIsOldVersion() {
     if (["http:", "https:"].indexOf(window.location.protocol) === -1) {
-        return;
+        return false;
     }
     const parts = window.location.pathname.split("/");
 
@@ -155,9 +155,9 @@ function showSwitcher(isOldVersion) {
     const current_doc_version = window.location.pathname.split("/")[1];
     const version_picker = document.createElement("select");
 
-    version_picker.appendChild(createOption("stable", false));
-    version_picker.appendChild(createOption("beta", false));
-    version_picker.appendChild(createOption("nightly", false));
+    version_picker.appendChild(createOption("stable", current_doc_version === "stable"));
+    version_picker.appendChild(createOption("beta", current_doc_version === "beta"));
+    version_picker.appendChild(createOption("nightly", current_doc_version === "nightly"));
 
     const version_parts = CURRENT_VERSION.split(".");
     for (let major = parseInt(version_parts[0]); major >= 1; --major) {