hotkey: Make 'Ctrl' hotkeys work with 'CMD' on MacOS.

We only have a couple hotkeys with this model, but they should both
do the correct corresponding thing on MacOS.

frontend_tests/node_tests/hotkey.js

@@ -14,6 +14,10 @@
 set_global('activity', {
 });
 
+set_global('navigator', {
+    userAgent: '',
+});
+
 set_global('page_params', {
 });
 
@@ -66,11 +70,12 @@ function stubbing(func_name_to_stub, test_function) {
         });
     }
 
-    function map_down(which, shiftKey, ctrlKey) {
+    function map_down(which, shiftKey, ctrlKey, metaKey) {
         return hotkey.get_keydown_hotkey({
             which: which,
             shiftKey: shiftKey,
             ctrlKey: ctrlKey,
+            metaKey: metaKey,
         });
     }
 
@@ -93,8 +98,8 @@ function stubbing(func_name_to_stub, test_function) {
     assert.equal(map_press(47).name, 'search'); // slash
     assert.equal(map_press(106).name, 'vim_down'); // j
 
-    assert.equal(map_down(219, false, true).name, 'escape');
-    assert.equal(map_down(75, false, true).name, 'search');
+    assert.equal(map_down(219, false, true).name, 'escape'); // ctrl + [
+    assert.equal(map_down(75, false, true).name, 'search'); // ctrl + k
 
     // More negative tests.
     assert.equal(map_down(47), undefined);
@@ -114,6 +119,17 @@ function stubbing(func_name_to_stub, test_function) {
     assert.equal(map_down(88, false, true), undefined); // ctrl + x
     assert.equal(map_down(78, false, true), undefined); // ctrl + n
     assert.equal(map_down(77, false, true), undefined); // ctrl + m
+    assert.equal(map_down(75, false, false, true), undefined); // cmd + k
+
+    // CMD tests for MacOS
+    global.navigator.userAgent = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.167 Safari/537.36";
+    assert.equal(map_down(219, false, false, true).name, 'escape'); // cmd + [
+    assert.equal(map_down(75, false, false, true).name, 'search'); // cmd + k
+
+    assert.equal(map_down(75, false, true, false), undefined); // ctrl + k
+
+    // Reset userAgent
+    global.navigator.userAgent = '';
 }());
 
 (function test_basic_chars() {

static/js/hotkey.js

@@ -47,7 +47,7 @@ var keydown_unshift_mappings = {
     40: {name: 'down_arrow', message_view_only: false}, // down arrow
 };
 
-var keydown_ctrl_mappings = {
+var keydown_cmd_or_ctrl_mappings = {
     75: {name: 'search', message_view_only: false}, // 'K'
     219: {name: 'escape', message_view_only: false}, // '['
 };
@@ -107,17 +107,21 @@ var keypress_mappings = {
 };
 
 exports.get_keydown_hotkey = function (e) {
-    if (e.metaKey || e.altKey) {
+    if (e.altKey) {
         return;
     }
 
     var hotkey;
-    if (e.ctrlKey) {
-        hotkey = keydown_ctrl_mappings[e.which];
+
+    var isCmdOrCtrl = /Mac/i.test(navigator.userAgent) ? e.metaKey : e.ctrlKey;
+    if (isCmdOrCtrl) {
+        hotkey = keydown_cmd_or_ctrl_mappings[e.which];
         if (hotkey) {
             return hotkey;
         }
         return;
+    } else if (e.metaKey || e.ctrlKey) {
+        return;
     }
 
     if (e.shiftKey) {