From 2e2cdfdb81a12b30a4a0929fc7cc2db78c9590b3 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Sun, 15 Jan 2017 20:58:18 -0500
Subject: [PATCH] bug fix: when applying change operations in reverse, apply
 their change units in reverse order

---
 src/core/Buffer.cc | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/core/Buffer.cc b/src/core/Buffer.cc
index 9f4856a..be08f6d 100644
--- a/src/core/Buffer.cc
+++ b/src/core/Buffer.cc
@@ -387,9 +387,21 @@ void Buffer::save_current_operation()
 
 void Buffer::apply_change_operation(const ChangeOperation & change_operation, bool forward)
 {
-    for (auto change_unit : change_operation.changes)
+    if (forward)
     {
-        apply_change_unit(change_unit, forward);
+        for (auto change_unit : change_operation.changes)
+        {
+            apply_change_unit(change_unit, forward);
+        }
+    }
+    else
+    {
+        for (auto i = change_operation.changes.rbegin();
+             i != change_operation.changes.rend();
+             i++)
+        {
+            apply_change_unit(*i, forward);
+        }
     }
 }