Rollup merge of #84150 - jsha:defer-search-js, r=GuillaumeGomez

rustdoc: move some search code into search.js

This reduces main.s from 3094 lines to 1587. Also it saves some bytes
of download in the case where search isn't used.

There were a fair number of variables that needed to be accessible in
both main.js and search.js, but I didn't want to put too many symbols in
the global namespace, so I consolidated much of the search-related
state and functions into a new object `window.searchState`.

Demo at https://hoffman-andrews.com/rust/move-search/std/?search=foo

src/librustdoc/html/layout.rs

@@ -113,7 +113,8 @@ crate fn render<T: Print, S: Print>(
     <section class=\"footer\"></section>\
     {after_content}\
     <div id=\"rustdoc-vars\" data-root-path=\"{root_path}\" data-current-crate=\"{krate}\" \
-       data-search-js=\"{root_path}search-index{suffix}.js\"></div>
+       data-search-index-js=\"{root_path}search-index{suffix}.js\" \
+       data-search-js=\"{static_root_path}search{suffix}.js\"></div>
     <script src=\"{static_root_path}main{suffix}.js\"></script>\
     {extra_scripts}\
 </body>\

src/librustdoc/html/render/write_shared.rs

@@ -222,6 +222,7 @@ pub(super) fn write_shared(
             &format!(" = {}", serde_json::to_string(&themes).unwrap()),
         ),
     )?;
+    write_minify("search.js", static_files::SEARCH_JS)?;
     write_minify("settings.js", static_files::SETTINGS_JS)?;
     if cx.shared.include_sources {
         write_minify("source-script.js", static_files::sidebar::SOURCE_SCRIPT)?;
@@ -409,7 +410,7 @@ pub(super) fn write_shared(
     write_crate("search-index.js", &|| {
         let mut v = String::from("var searchIndex = JSON.parse('{\\\n");
         v.push_str(&all_indexes.join(",\\\n"));
-        v.push_str("\\\n}');\ninitSearch(searchIndex);");
+        v.push_str("\\\n}');\nif (window.initSearch) {window.initSearch(searchIndex)};");
         Ok(v.into_bytes())
     })?;
 

src/librustdoc/html/static_files.rs

@@ -24,6 +24,9 @@ crate static NORMALIZE_CSS: &str = include_str!("static/normalize.css");
 /// including search behavior and docblock folding, among others.
 crate static MAIN_JS: &str = include_str!("static/main.js");
 
+/// The file contents of `search.js`, which contains the search behavior.
+crate static SEARCH_JS: &str = include_str!("static/search.js");
+
 /// The file contents of `settings.js`, which contains the JavaScript used to handle the settings
 /// page.
 crate static SETTINGS_JS: &str = include_str!("static/settings.js");

src/tools/rustdoc-js/tester.js

@@ -246,7 +246,7 @@ function lookForEntry(entry, data) {
     return null;
 }
 
-function loadMainJsAndIndex(mainJs, searchIndex, storageJs, crate) {
+function loadSearchJsAndIndex(searchJs, searchIndex, storageJs, crate) {
     if (searchIndex[searchIndex.length - 1].length === 0) {
         searchIndex.pop();
     }
@@ -270,9 +270,9 @@ function loadMainJsAndIndex(mainJs, searchIndex, storageJs, crate) {
     ALIASES = {};
     finalJS += 'window = { "currentCrate": "' + crate + '", rootPath: "../" };\n';
     finalJS += loadThings(["hasOwnProperty", "onEach"], 'function', extractFunction, storageJs);
-    finalJS += loadThings(arraysToLoad, 'array', extractArrayVariable, mainJs);
-    finalJS += loadThings(variablesToLoad, 'variable', extractVariable, mainJs);
-    finalJS += loadThings(functionsToLoad, 'function', extractFunction, mainJs);
+    finalJS += loadThings(arraysToLoad, 'array', extractArrayVariable, searchJs);
+    finalJS += loadThings(variablesToLoad, 'variable', extractVariable, searchJs);
+    finalJS += loadThings(functionsToLoad, 'function', extractFunction, searchJs);
 
     var loaded = loadContent(finalJS);
     var index = loaded.buildIndex(searchIndex.rawSearchIndex);
@@ -382,12 +382,12 @@ function runChecks(testFile, loaded, index) {
 }
 
 function load_files(doc_folder, resource_suffix, crate) {
-    var mainJs = readFile(path.join(doc_folder, "main" + resource_suffix + ".js"));
+    var searchJs = readFile(path.join(doc_folder, "search" + resource_suffix + ".js"));
     var storageJs = readFile(path.join(doc_folder, "storage" + resource_suffix + ".js"));
     var searchIndex = readFile(
         path.join(doc_folder, "search-index" + resource_suffix + ".js")).split("\n");
 
-    return loadMainJsAndIndex(mainJs, searchIndex, storageJs, crate);
+    return loadSearchJsAndIndex(searchJs, searchIndex, storageJs, crate);
 }
 
 function showHelp() {