From 24bc90f9cc9e74b930bcf4655e93805632382046 Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <richard@matrix.org>
Date: Tue, 11 Oct 2016 13:54:57 +0100
Subject: [PATCH] Fix flaky TimelinePanel test

The 'should load new events even if you are scrolled up' test was sometimes
failing. It turned out that pagination *sometimes* wasn't starting soon enough
after setting the scrollTop, and awaitPaginationCompletion was incorrectly
believing it to have already been and gone.

Add an awaitScroll to make sure that we wait long enough for the pagination to
begin.
---
 .../structures/TimelinePanel-test.js          | 25 ++++++++++---------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/test/components/structures/TimelinePanel-test.js b/test/components/structures/TimelinePanel-test.js
index 993973cb1d..cbfa4de990 100644
--- a/test/components/structures/TimelinePanel-test.js
+++ b/test/components/structures/TimelinePanel-test.js
@@ -41,11 +41,15 @@ describe('TimelinePanel', function() {
     var timeline;
     var parentDiv;
 
-    function mkMessage(opts) {
+    // make a dummy message. eventNum is put in the message text to help
+    // identification during debugging, and also in the timestamp so that we
+    // don't get lots of events with the same timestamp.
+    function mkMessage(eventNum, opts) {
         return test_utils.mkMessage(
             {
                 event: true, room: ROOM_ID, user: USER_ID,
-                ts: Date.now(),
+                ts: Date.now() + eventNum,
+                msg: "Event " + eventNum,
                 ... opts,
             });
     }
@@ -97,7 +101,7 @@ describe('TimelinePanel', function() {
         // enough events to allow us to scroll back
         var N_EVENTS = 30;
         for (var i = 0; i < N_EVENTS; i++) {
-            timeline.addEvent(mkMessage());
+            timeline.addEvent(mkMessage(i));
         }
 
         var scrollDefer;
@@ -148,7 +152,7 @@ describe('TimelinePanel', function() {
             console.log("adding event");
 
             // a new event!
-            var ev = mkMessage();
+            var ev = mkMessage(31);
             timeline.addEvent(ev);
             panel.onRoomTimeline(ev, room, false, false, {
                 liveEvent: true,
@@ -161,7 +165,9 @@ describe('TimelinePanel', function() {
             expect(scryEventTiles(panel).length).toEqual(N_EVENTS);
 
             scrollingDiv.scrollTop = 10;
-        }).delay(0).then(awaitPaginationCompletion).then(() => {
+
+            return awaitScroll();
+        }).then(awaitPaginationCompletion).then(() => {
             expect(scryEventTiles(panel).length).toEqual(N_EVENTS+1);
         }).done(done, done);
     });
@@ -171,12 +177,7 @@ describe('TimelinePanel', function() {
         // joining a room
         var d = Date.now();
         for (var i = 0; i < 3; i++) {
-            timeline.addEvent(test_utils.mkMessage(
-                {
-                    event: true, room: ROOM_ID, user: USER_ID,
-                    ts: d+i,
-                }
-            ));
+            timeline.addEvent(mkMessage(i));
         }
         timeline.setPaginationToken('tok', EventTimeline.BACKWARDS);
 
@@ -230,7 +231,7 @@ describe('TimelinePanel', function() {
 
         // fill the timeline with lots of events
         for (var i = 0; i < N_EVENTS; i++) {
-            timeline.addEvent(mkMessage({msg: "Event "+i}));
+            timeline.addEvent(mkMessage(i));
         }
         console.log("added events to timeline");