Add a test spec for autocompletion

spec/autocomplete.js

+(function (root, factory) {
+    define([
+        "jasmine",
+        "mock",
+        "test-utils"
+        ], factory);
+} (this, function (jasmine, mock, test_utils) {
+    "use strict";
+    const _ = converse.env._;
+    const $iq = converse.env.$iq;
+    const $msg = converse.env.$msg;
+    const $pres = converse.env.$pres;
+    const Strophe = converse.env.Strophe;
+    const u = converse.env.utils;
+    const sizzle = converse.env.sizzle;
+
+    return describe("A groupchat textarea", function () {
+
+        it("autocompletes when the user presses tab",
+            mock.initConverseWithPromises(
+                null, ['rosterGroupsFetched'], {},
+                    function (done, _converse) {
+
+            test_utils.openAndEnterChatRoom(_converse, 'lounge', 'localhost', 'dummy')
+            .then(() => {
+                const view = _converse.chatboxviews.get('lounge@localhost');
+                expect(view.model.occupants.length).toBe(1);
+                const presence = $pres({
+                        'to': 'dummy@localhost/resource',
+                        'from': 'lounge@localhost/some1'
+                    })
+                    .c('x', {xmlns: Strophe.NS.MUC_USER})
+                    .c('item', {
+                        'affiliation': 'none',
+                        'jid': 'some1@localhost/resource',
+                        'role': 'participant'
+                    });
+                _converse.connection._dataRecv(test_utils.createRequest(presence));
+                expect(view.model.occupants.length).toBe(2);
+
+                const textarea = view.el.querySelector('textarea.chat-textarea');
+                textarea.value = "hello som";
+
+                // Press tab
+                view.keyPressed({
+                    target: textarea,
+                    preventDefault: _.noop,
+                    keyCode: 9
+                });
+                expect(view.el.querySelector('.suggestion-box__results').hidden).toBeFalsy();
+                done();
+            }).catch(_.partial(console.error, _));
+        }));
+    });
+}));

tests/runner.js

@@ -201,6 +201,7 @@ var specs = [
     "spec/user-details-modal",
     "spec/messages",
     "spec/chatroom",
+    "spec/autocomplete",
     "spec/minchats",
     "spec/notification",
     "spec/login",