From 4cc9c9997e5d9f190a5cfaa28ea1aac0fae34b4b Mon Sep 17 00:00:00 2001
From: Maxime Coste <mawww@kakoune.org>
Date: Wed, 16 May 2018 20:41:02 +1000
Subject: [PATCH] compute_line_modifications: avoid potentially long iteration

---
 src/line_modification.cc | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/line_modification.cc b/src/line_modification.cc
index df2b9cbc..da3ee87f 100644
--- a/src/line_modification.cc
+++ b/src/line_modification.cc
@@ -73,10 +73,13 @@ Vector<LineModification> compute_line_modifications(const Buffer& buffer, size_t
             }
             next = res.erase(next, delend);
 
-            for (auto it = next; it != res.end(); ++it)
-                it->new_line -= diff;
+            if (diff != 0)
+            {
+                for (auto it = next; it != res.end(); ++it)
+                    it->new_line -= diff;
+            }
         }
-        else
+        else if (diff != 0)
         {
             for (auto it = next; it != res.end(); ++it)
                 it->new_line += diff;