Fix search-index.js on-demand load mode compatiblity

rustdoc merged a new PR [#82310](rust-lang/rust#82310) a few days ago, this cause breaking changes to this extension. This commit aims to fix this incompatibility.

Author: Folyd

extension/script/add-rustc-search-index.js

@@ -1,12 +1,59 @@
-(function() {
-    // Parse crate info from location pathname.
-    let [_, crateVersion, crateName] = location.pathname.slice(1).split("/");
-    window.postMessage({
-        direction: "rust-search-extension",
-        message: {
-            crateName,
-            crateVersion,
-            searchIndex: window.searchIndex,
-        },
-    }, "*");
+(function () {
+    function sendSearchIndex() {
+        if (location.hostname === "docs.rs") { // docs.rs pages
+            // Parse crate info from location pathname.
+            let [_, crateVersion, crateName] = location.pathname.slice(1).split("/");
+            window.postMessage({
+                direction: "rust-search-extension",
+                message: {
+                    crateName,
+                    crateVersion,
+                    searchIndex: window.searchIndex,
+                },
+            }, "*");
+        } else if (location.pathname.startsWith("/nightly/nightly-rustc/")
+            && location.hostname === "doc.rust-lang.org") { // rustc pages
+            window.postMessage({
+                direction: 'rust-search-extension:rustc',
+                message: {
+                    searchIndex: window.searchIndex,
+                },
+            }, "*");
+        } else { // stable/nightly pages
+            const STD_CRATES = ['std', 'test', 'proc_macro'];
+
+            // Remove unnecessary std crate's search index, such as core, alloc, etc
+            function cleanSearchIndex() {
+                let searchIndex = {};
+                STD_CRATES.forEach(crate => {
+                    searchIndex[crate] = window.searchIndex[crate];
+                });
+                return searchIndex;
+            }
+
+            window.postMessage({
+                direction: `rust-search-extension:std`,
+                message: {
+                    searchIndex: cleanSearchIndex(window.searchIndex),
+                },
+            }, "*");
+        }
+        console.log("Send search index success.");
+    }
+
+    if (window.searchIndex) {
+        sendSearchIndex();
+    } else {
+        // Due to the new search-index.js on-demand load mode after PR #82310 has been merged.
+        // We need to trigger a manual search-index.js load here.
+        console.log("Not search index found, start loading...")
+        let rustdocVars = document.getElementById("rustdoc-vars");
+        if (rustdocVars) {
+            let searchJS = rustdocVars.attributes["data-search-js"].value;
+            let script = document.createElement('script');
+            script.src = searchJS;
+            script.onload = sendSearchIndex;
+            document.head.append(script);
+        }
+    }
 })();

extension/script/add-search-index.js

@@ -16,7 +16,7 @@ document.addEventListener("DOMContentLoaded", () => {
             // Check version between localStorage and today to ensure update search index once a day.
             return;
         }
-        injectScripts(["script/add-std-search-index.js"]);
+        injectScripts(["script/add-search-index.js"]);
     }
 });
 

extension/script/add-std-search-index.js

@@ -7,7 +7,7 @@ document.addEventListener("DOMContentLoaded", () => {
                 // Check version to ensure update search index once a day.
                 return;
             }
-            injectScripts(["script/add-rustc-search-index.js"]);
+            injectScripts(["script/add-search-index.js"]);
         }
     );
 });

extension/script/doc-rust-lang-org.js

@@ -14,7 +14,7 @@ local json = manifest.new(
 )
              .addIcons(icons())
              .addPermissions(['storage'])
-             .addWebAccessibleResources(utils.js_files('script', ['add-search-index', 'add-std-search-index', 'add-rustc-search-index']))
+             .addWebAccessibleResources(utils.js_files('script', ['add-search-index']))
              .addBackgroundScripts(['settings.js', 'deminifier.js'])
              .addBackgroundScripts(utils.js_files('search', ['algorithm', 'book', 'crate', 'attribute', 'caniuse', 'lint']))
              .addBackgroundScripts(utils.js_files('search/docs', ['base', 'std', 'crate-doc', 'rustc']))