From 3c8df764be5ca2dc2ff423258ee7d14eb5409db2 Mon Sep 17 00:00:00 2001
From: Maxime Coste <frrrwww@gmail.com>
Date: Tue, 30 Jul 2013 19:09:36 +0100
Subject: [PATCH] fix insert mode erase utf-8 handling, add unit test

---
 src/editor.cc     | 4 +++-
 src/unit_tests.cc | 9 ++++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/editor.cc b/src/editor.cc
index c03fd396c..ae156041e 100644
--- a/src/editor.cc
+++ b/src/editor.cc
@@ -558,8 +558,10 @@ void IncrementalInserter::erase()
     auto& buffer = m_editor.buffer();
     for (auto& sel : m_editor.m_selections)
     {
+        if (sel.last() == BufferCoord{0,0})
+            continue;
         auto pos = buffer.iterator_at(sel.last());
-        buffer.erase(pos-1, pos);
+        buffer.erase(utf8::previous(pos), pos);
     }
 }
 
diff --git a/src/unit_tests.cc b/src/unit_tests.cc
index 5058bb915..c0d8a15b2 100644
--- a/src/unit_tests.cc
+++ b/src/unit_tests.cc
@@ -94,7 +94,7 @@ void test_editor()
 
 void test_incremental_inserter()
 {
-    Buffer buffer("test", Buffer::Flags::None, { "test\n", "\n", "youpi\n", "matin\n" });
+    Buffer buffer("test", Buffer::Flags::None, { "test\n", "\n", "yoüpi\n", "matin\n" });
     Editor editor(buffer);
 
     editor.select({0,0});
@@ -106,6 +106,13 @@ void test_incremental_inserter()
         kak_assert(editor.selections().front().last() == BufferCoord{0 COMMA 0});
         kak_assert(*buffer.begin() == L'\n');
     }
+    // check utf-8 erase
+    editor.select({3,4});
+    {
+        IncrementalInserter inserter(editor, InsertMode::Insert);
+        inserter.erase();
+        kak_assert(editor.selections().back().last() == BufferCoord{3 COMMA 2});
+    }
     kak_assert(not editor.is_editing());
 }