Fixes #1024

Use sizzle, otherwise we sometimes get null returned.

CHANGES.md

@@ -3,11 +3,16 @@
 ## 3.3.4 (Unreleased)
 
 - Avoid `eval` (via `_.template` from lodash).
-- Bugfix. Avatars weren't being shown.
-- Bugfix. Bookmarks list and open rooms list weren't recreated after logging in for a 2nd time (without reloading the browser).
 - Don't show bookmark toggles when PEP bookmarking not supported by the XMPP server.
 - Add LibreJS support
 
+### Bugfixes
+
+- Avatars weren't being shown.
+- Bookmarks list and open rooms list weren't recreated after logging in for a 2nd time (without reloading the browser).
+- #1024 null reference on MUC Invite
+- #1025 OTR lock icon disappears
+
 ## 3.3.3 (2018-02-14)
 
 ### Bugfixes

spec/chatroom.js

@@ -1423,16 +1423,15 @@
                     var from_jid = name.replace(/ /g,'.').toLowerCase() + '@localhost';
                     var room_jid = 'lounge@localhost';
                     var reason = "Please join this chat room";
-                    var message = $(
-                        "<message from='"+from_jid+"' to='"+_converse.bare_jid+"'>" +
-                            "<x xmlns='jabber:x:conference'" +
-                                "jid='"+room_jid+"'" +
-                                "reason='"+reason+"'/>"+
-                        "</message>"
-                    )[0];
+
                     expect(_converse.chatboxes.models.length).toBe(1);
                     expect(_converse.chatboxes.models[0].id).toBe("controlbox");
-                    _converse.onDirectMUCInvitation(message);
+
+                    var stanza = Strophe.xmlHtmlNode(
+                        '<message xmlns="jabber:client" to="'+_converse.bare_jid+'" from="'+from_jid+'" id="9bceb415-f34b-4fa4-80d5-c0d076a24231">'+
+                            '<x xmlns="jabber:x:conference" jid="'+room_jid+'" reason="'+reason+'"/>'+
+                        '</message>').firstChild;
+                    _converse.onDirectMUCInvitation(stanza);
                     expect(window.confirm).toHaveBeenCalledWith(
                         name + ' has invited you to join a chat room: '+ room_jid +
                         ', and left the following reason: "'+reason+'"');

src/converse-muc.js

@@ -2839,7 +2839,7 @@
                  *  (XMLElement) message: The message stanza containing the
                  *        invitation.
                  */
-                const x_el = message.querySelector('x[xmlns="jabber:x:conference"]'),
+                const x_el = sizzle('x[xmlns="jabber:x:conference"]', message).pop(),
                     from = Strophe.getBareJidFromJid(message.getAttribute('from')),
                     room_jid = x_el.getAttribute('jid'),
                     reason = x_el.getAttribute('reason');