From 0aa9af3dfc6460291bbb37f5f39408cacd09be61 Mon Sep 17 00:00:00 2001
From: David Glasser <glasser@meteor.com>
Date: Mon, 17 Mar 2014 11:10:06 -0700
Subject: [PATCH] Make some white-box tests less flaky

If we want the *internal* state of the oplog driver to be consistent, we
need to make sure that we start our observes at a consistent point in
the oplog.  (ie, initial inserts need to have been fully processed, so
that we don't process them during the original QUERYING phase, which can
give us a different unpublished buffer.)

Note that only the white-box tests (looked at _unpublishedBuffer, eg)
appeared to be flaky: the actual docs published seemed to be correct in
all cases.
---
 .../mongo-livedata/mongo_livedata_tests.js    | 24 ++++++++++++++-----
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/packages/mongo-livedata/mongo_livedata_tests.js b/packages/mongo-livedata/mongo_livedata_tests.js
index 48dfa6fa92..20f2126886 100644
--- a/packages/mongo-livedata/mongo_livedata_tests.js
+++ b/packages/mongo-livedata/mongo_livedata_tests.js
@@ -818,6 +818,8 @@ if (Meteor.isServer) {
 
     // Insert a doc and start observing.
     var docId1 = ins({foo: 22, bar: 5});
+    waitUntilOplogCaughtUp();
+
     // State: [ 5:1 | ]!
     var o = observer();
     var usesOplog = o.handle._multiplexer._observeDriver._usesOplog;
@@ -1154,6 +1156,10 @@ if (Meteor.isServer) {
       ids[i] = ins({ x: x, y: i });
     });
 
+    // Ensure that we are past all the 'i' entries before we run the query, so
+    // that we get the expected phase transitions.
+    waitUntilOplogCaughtUp();
+
     var o = observer();
     var usesOplog = o.handle._multiplexer._observeDriver._usesOplog;
     //  x: [1 1 2 | 2 3 3] 4 5 5 5  9
@@ -2407,8 +2413,7 @@ Meteor.isServer && Tinytest.add("mongo-livedata - oplog - include selector field
   // during the observeChanges, the bug in question is not consistently
   // reproduced.) We don't have to do this for polling observe (eg
   // --disable-oplog).
-  var oplog = MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle;
-  oplog && oplog.waitUntilCaughtUp();
+  waitUntilOplogCaughtUp();
 
   var output = [];
   var handle = coll.find({a: 1, b: 2}, {fields: {c: 1}}).observeChanges({
@@ -2450,8 +2455,7 @@ Meteor.isServer && Tinytest.add("mongo-livedata - oplog - transform", function (
   // during the observeChanges, the bug in question is not consistently
   // reproduced.) We don't have to do this for polling observe (eg
   // --disable-oplog).
-  var oplog = MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle;
-  oplog && oplog.waitUntilCaughtUp();
+  waitUntilOplogCaughtUp();
 
   var cursor = coll.find({}, {transform: function (doc) {
     return doc.x;
@@ -2513,8 +2517,7 @@ Meteor.isServer && Tinytest.add("mongo-livedata - oplog - drop collection", func
 
   // Wait until we've processed the insert oplog entry, so that we are in a
   // steady state (and we don't see the dropped docs because we are FETCHING).
-  var oplog = MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle;
-  oplog && oplog.waitUntilCaughtUp();
+  waitUntilOplogCaughtUp();
 
   // Drop the collection. Should remove all docs.
   runInFence(function () {
@@ -2664,3 +2667,12 @@ testAsyncMulti("mongo-livedata - oplog - update EJSON", [
     self.handle.stop();
   }
 ]);
+
+
+var waitUntilOplogCaughtUp = function () {
+  var oplogHandle =
+        MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle;
+  if (oplogHandle)
+    oplogHandle.waitUntilCaughtUp();
+};
+