SERVER-26016 Add a basic test of oplog replay on startup

Fixes a small but important bug in SERVER-7200.

1 files changed, 5 insertions, 4 deletions

diff --git a/src/mongo/db/repl/sync_tail.cpp b/src/mongo/db/repl/sync_tail.cpp
index 91d6592ad58..992ed5b3781 100644
--- a/src/mongo/db/repl/sync_tail.cpp
+++ b/src/mongo/db/repl/sync_tail.cpp
@@ -804,10 +804,11 @@ void SyncTail::oplogApplication(ReplicationCoordinator* replCoord) {
         // Do the work.
         multiApply(&txn, ops.releaseBatch());
 
-        // Update various things that care about our last applied optime.
-        setNewTimestamp(lastOpTimeInBatch.getTimestamp());
-        StorageInterface::get(&txn)->setAppliedThrough(&txn, lastOpTimeInBatch);
-        finalizer->record(lastOpTimeInBatch);
+        // Update various things that care about our last applied optime. Tests rely on 2 happening
+        // before 3 even though it isn't strictly necessary. The order of 1 doesn't matter.
+        setNewTimestamp(lastOpTimeInBatch.getTimestamp());                        // 1
+        StorageInterface::get(&txn)->setAppliedThrough(&txn, lastOpTimeInBatch);  // 2
+        finalizer->record(lastOpTimeInBatch);                                     // 3
     }
 }