From d7e1cab11679cd983359b22c3b29188264d44ceb Mon Sep 17 00:00:00 2001
From: Maxime Coste <frrrwww@gmail.com>
Date: Tue, 3 Jul 2012 19:13:16 +0200
Subject: [PATCH] DisplayAtom: support empty replacement

---
 src/display_buffer.cc | 24 ++++++++++++++++++------
 src/display_buffer.hh | 10 +++++++++-
 2 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/src/display_buffer.cc b/src/display_buffer.cc
index 303f1b26..3926e227 100644
--- a/src/display_buffer.cc
+++ b/src/display_buffer.cc
@@ -8,10 +8,15 @@ namespace Kakoune
 
 String DisplayAtom::content() const
 {
-    if (m_replacement_text.empty())
+    switch (m_content_mode)
+    {
+    case BufferText:
         return m_begin.buffer().string(m_begin, m_end);
-    else
+    case ReplacementText:
         return m_replacement_text;
+    }
+    assert(false);
+    return "";
 }
 
 static DisplayCoord advance_coord(const DisplayCoord& pos,
@@ -40,17 +45,23 @@ static DisplayCoord advance_coord(const DisplayCoord& pos,
     }
     return res;
 }
+
 DisplayCoord DisplayAtom::end_coord() const
 {
-    if (m_replacement_text.empty())
+    switch (m_content_mode)
+    {
+    case BufferText:
         return advance_coord(m_coord, m_begin, m_end);
-    else
+    case ReplacementText:
         return advance_coord(m_coord, m_replacement_text);
+    }
+    assert(false);
+    return { 0, 0 };
 }
 
 BufferIterator DisplayAtom::iterator_at(const DisplayCoord& coord) const
 {
-    if (not m_replacement_text.empty() or coord <= m_coord)
+    if (m_content_mode != BufferText or coord <= m_coord)
         return m_begin;
 
     DisplayCoord pos = m_coord;
@@ -74,7 +85,7 @@ DisplayCoord DisplayAtom::line_and_column_at(const BufferIterator& iterator) con
 {
     assert(iterator >= m_begin and iterator < m_end);
 
-    if (not m_replacement_text.empty())
+    if (m_content_mode != BufferText)
         return m_coord;
 
     return advance_coord(m_coord, m_begin, iterator);
@@ -140,6 +151,7 @@ void DisplayBuffer::check_invariant() const
 void DisplayBuffer::replace_atom_content(iterator atom,
                                          const String& replacement)
 {
+    atom->m_content_mode = DisplayAtom::ReplacementText;
     atom->m_replacement_text = replacement;
 
     // update coordinates of subsequents atoms
diff --git a/src/display_buffer.hh b/src/display_buffer.hh
index 36b4803e..89561bde 100644
--- a/src/display_buffer.hh
+++ b/src/display_buffer.hh
@@ -57,7 +57,8 @@ struct DisplayAtom
                 Color fg_color = Color::Default,
                 Color bg_color = Color::Default,
                 Attribute attribute = Attributes::Normal)
-        : m_coord(coord),
+        : m_content_mode(BufferText),
+          m_coord(coord),
           m_begin(begin), m_end(end),
           m_fg_color(fg_color),
           m_bg_color(bg_color),
@@ -86,6 +87,13 @@ struct DisplayAtom
 private:
     friend class DisplayBuffer;
 
+    enum ContentMode
+    {
+        BufferText,
+        ReplacementText
+    };
+    ContentMode    m_content_mode;
+
     DisplayCoord   m_coord;
     BufferIterator m_begin;
     BufferIterator m_end;