From 704050da2334c465784954d81c8990c4bc7a92c5 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Sun, 8 Nov 2020 14:49:29 +0100
Subject: [PATCH] Make keyboard interactions in the settings menu more pleasant

---
 src/librustdoc/html/static/main.js     | 45 +++++++++++++-------------
 src/librustdoc/html/static/settings.js | 25 +++++++++++---
 2 files changed, 44 insertions(+), 26 deletions(-)

diff --git a/src/librustdoc/html/static/main.js b/src/librustdoc/html/static/main.js
index 10342679cf474..4d75195fb81d4 100644
--- a/src/librustdoc/html/static/main.js
+++ b/src/librustdoc/html/static/main.js
@@ -40,6 +40,29 @@ if (!DOMTokenList.prototype.remove) {
     };
 }
 
+
+// Gets the human-readable string for the virtual-key code of the
+// given KeyboardEvent, ev.
+//
+// This function is meant as a polyfill for KeyboardEvent#key,
+// since it is not supported in Trident.  We also test for
+// KeyboardEvent#keyCode because the handleShortcut handler is
+// also registered for the keydown event, because Blink doesn't fire
+// keypress on hitting the Escape key.
+//
+// So I guess you could say things are getting pretty interoperable.
+function getVirtualKey(ev) {
+    if ("key" in ev && typeof ev.key != "undefined") {
+        return ev.key;
+    }
+
+    var c = ev.charCode || ev.keyCode;
+    if (c == 27) {
+        return "Escape";
+    }
+    return String.fromCharCode(c);
+}
+
 function getSearchInput() {
     return document.getElementsByClassName("search-input")[0];
 }
@@ -323,28 +346,6 @@ function defocusSearchBar() {
         }
     }
 
-    // Gets the human-readable string for the virtual-key code of the
-    // given KeyboardEvent, ev.
-    //
-    // This function is meant as a polyfill for KeyboardEvent#key,
-    // since it is not supported in Trident.  We also test for
-    // KeyboardEvent#keyCode because the handleShortcut handler is
-    // also registered for the keydown event, because Blink doesn't fire
-    // keypress on hitting the Escape key.
-    //
-    // So I guess you could say things are getting pretty interoperable.
-    function getVirtualKey(ev) {
-        if ("key" in ev && typeof ev.key != "undefined") {
-            return ev.key;
-        }
-
-        var c = ev.charCode || ev.keyCode;
-        if (c == 27) {
-            return "Escape";
-        }
-        return String.fromCharCode(c);
-    }
-
     function getHelpElement() {
         buildHelperPopup();
         return document.getElementById("help");
diff --git a/src/librustdoc/html/static/settings.js b/src/librustdoc/html/static/settings.js
index da3378ccf0dd0..daed6e731343e 100644
--- a/src/librustdoc/html/static/settings.js
+++ b/src/librustdoc/html/static/settings.js
@@ -1,5 +1,5 @@
 // Local js definitions:
-/* global getCurrentValue, updateLocalStorage, updateSystemTheme */
+/* global getCurrentValue, getVirtualKey, updateLocalStorage, updateSystemTheme */
 
 (function () {
     function changeSetting(settingName, value) {
@@ -14,10 +14,25 @@
         }
     }
 
+    function handleKey(ev) {
+        // Don't interfere with browser shortcuts
+        if (ev.ctrlKey || ev.altKey || ev.metaKey) {
+            return;
+        }
+        switch (getVirtualKey(ev)) {
+            case "Enter":
+            case "Return":
+            case "Space":
+                ev.target.checked = !ev.target.checked;
+                ev.preventDefault();
+                break;
+        }
+    }
+
     function setEvents() {
         var elems = {
-            toggles: document.getElementsByClassName("slider"),
-            selects: document.getElementsByClassName("select-wrapper")
+            toggles: Array.prototype.slice.call(document.getElementsByClassName("slider")),
+            selects: Array.prototype.slice.call(document.getElementsByClassName("select-wrapper")),
         };
         var i;
 
@@ -32,6 +47,8 @@
                 toggle.onchange = function() {
                     changeSetting(this.id, this.checked);
                 };
+                toggle.onkeyup = handleKey;
+                toggle.onkeyrelease = handleKey;
             }
         }
 
@@ -50,5 +67,5 @@
         }
     }
 
-    setEvents();
+    window.addEventListener("DOMContentLoaded", setEvents);
 })();