From d142db80f2393d7b74b2088cf8df986b592b9675 Mon Sep 17 00:00:00 2001
From: Maxime Coste <mawww@kakoune.org>
Date: Mon, 27 Nov 2017 17:29:19 +0800
Subject: [PATCH] Fix compute_modified_ranges corner case that would crash on
 undo

Fixes #1506
Fixes #1215
---
 src/selection.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/selection.cc b/src/selection.cc
index 0ea173ce..3574afaa 100644
--- a/src/selection.cc
+++ b/src/selection.cc
@@ -167,6 +167,8 @@ Vector<Selection> compute_modified_ranges(Buffer& buffer, size_t timestamp)
 
         kak_assert(std::is_sorted(ranges.begin() + prev_size, ranges.end(), compare_selections));
         std::inplace_merge(ranges.begin(), ranges.begin() + prev_size, ranges.end(), compare_selections);
+        // The newly added ranges might be overlapping pre-existing ones
+        ranges.erase(merge_overlapping(ranges.begin(), ranges.end(), dummy, overlaps), ranges.end());
     }
 
     const auto end_coord = buffer.end_coord();