From 64a09fca0f8cc2bce6629eddf3707bc52565515f Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Mon, 26 Dec 2016 14:01:24 -0500
Subject: [PATCH] add Buffer::erase_code_point()

---
 src/core/Buffer.cc | 18 ++++++++++++++++++
 src/core/Buffer.h  |  1 +
 2 files changed, 19 insertions(+)

diff --git a/src/core/Buffer.cc b/src/core/Buffer.cc
index 71228b8..52dd692 100644
--- a/src/core/Buffer.cc
+++ b/src/core/Buffer.cc
@@ -180,3 +180,21 @@ void Buffer::insert_code_point(uint32_t code_point)
         m_insert_position += bytes;
     }
 }
+
+void Buffer::erase_code_point(const Buffer::Iterator & position)
+{
+    if (position.valid())
+    {
+        uint8_t bytes = 0u;
+        uint32_t code_point = Encoding::decode(m_encoding, position.address(), &bytes);
+        m_gap_buffer->erase(position.offset(), bytes);
+        ssize_t lines = (code_point == '\n') ? -1 : 0;
+        for (auto iterator : m_iterators)
+        {
+            if (*iterator > position)
+            {
+                iterator->warp(-(ssize_t)bytes, lines);
+            }
+        }
+    }
+}
diff --git a/src/core/Buffer.h b/src/core/Buffer.h
index f93e716..e37ef74 100644
--- a/src/core/Buffer.h
+++ b/src/core/Buffer.h
@@ -106,6 +106,7 @@ public:
     void exit_insert_mode();
     bool insert_mode() const { return m_insert_mode; }
     void insert_code_point(uint32_t code_point);
+    void erase_code_point(const Buffer::Iterator & position);
 
 protected:
     bool m_eol_at_eof;