Update list of available search filters in help menu

Author: GuillaumeGomez

src/librustdoc/html/static/js/main.js

@@ -1634,14 +1634,23 @@ function preLoadCss(cssUrl) {
         addClass(div_shortcuts, "shortcuts");
         div_shortcuts.innerHTML = "<h2>Keyboard Shortcuts</h2><dl>" + shortcuts + "</dl></div>";
 
+        // FIXME: Find a better way to keep this list up-to-date with search.js `itemTypes` and
+        // `rustdoc::formats::item_type::ItemType`.
+        let filters = [
+            "keyword", "primitive", "mod", "externcrate", "import", "struct", "enum", "fn", "type",
+            "static", "trait", "impl", "tymethod", "method", "structfield", "variant", "macro",
+            "associatedtype", "constant", "associatedconstant", "union", "foreigntype",
+            "existential", "attr", "derive", "traitalias", "generic", "attribute",
+        ];
+        filters.sort();
+        filters = filters.map(f => `<code>${f}</code>`);
+        const last = filters.pop();
         const infos = [
             `For a full list of all search features, take a look \
              <a href="${drloChannel}/rustdoc/read-documentation/search.html">here</a>.`,
             "Prefix searches with a type followed by a colon (e.g., <code>fn:</code>) to \
              restrict the search to a given item kind.",
-            "Accepted kinds are: <code>fn</code>, <code>mod</code>, <code>struct</code>, \
-             <code>enum</code>, <code>trait</code>, <code>type</code>, <code>macro</code>, \
-             and <code>const</code>.",
+            `Accepted kinds are: ${filters.join(', ')} and ${last}.`,
             "Search functions by type signature (e.g., <code>vec -&gt; usize</code> or \
              <code>-&gt; vec</code> or <code>String, enum:Cow -&gt; bool</code>)",
             "You can look for items with an exact name by putting double quotes around \