From 99d6e507d8dfa6c2ba0a40798d148bb487f9f7f0 Mon Sep 17 00:00:00 2001
From: Smaug123 <patrick+github@patrickstevens.co.uk>
Date: Sat, 12 Nov 2022 20:57:39 +0000
Subject: [PATCH] Resolve one TODO

---
 Raft/Server.fs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Raft/Server.fs b/Raft/Server.fs
index e8400af..b780cdb 100644
--- a/Raft/Server.fs
+++ b/Raft/Server.fs
@@ -454,8 +454,8 @@ type Server<'a>
                 | None ->
                     // The leader knows what we've committed, so it won't try and give us anything further than
                     // the element immediately past our persisted log.
-                    // TODO - why can't this be -1?
-                    assert (desiredLogInsertionPosition = 1<LogIndex> + persistentState.CurrentLogIndex)
+                    if desiredLogInsertionPosition <> 1<LogIndex> + persistentState.CurrentLogIndex then
+                        failwith "Logic error: the leader has tried to update an entry from our future."
                     // The leader's message is after our log. Append.
                     persistentState.AppendToLog toInsert toInsertTerm