From 50cacc0758ea7e6acd7dcc350f8dbb2e6559a30e Mon Sep 17 00:00:00 2001
From: Maxime Coste <mawww@kakoune.org>
Date: Mon, 11 Jul 2022 18:17:51 +1000
Subject: [PATCH] Fix buffer location of column highlighter's past-eol atoms

Using buffer end was confusing Window::display_position that
assumes display atom buffer locations are always increasing.
---
 src/display_buffer.cc | 3 ++-
 src/display_buffer.hh | 2 +-
 src/highlighters.cc   | 8 ++++++--
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/display_buffer.cc b/src/display_buffer.cc
index a1dfbc36..2b377310 100644
--- a/src/display_buffer.cc
+++ b/src/display_buffer.cc
@@ -134,7 +134,7 @@ DisplayLine::iterator DisplayLine::insert(iterator it, DisplayAtom atom)
     return res;
 }
 
-void DisplayLine::push_back(DisplayAtom atom)
+DisplayAtom& DisplayLine::push_back(DisplayAtom atom)
 {
     if (atom.has_buffer_range())
     {
@@ -142,6 +142,7 @@ void DisplayLine::push_back(DisplayAtom atom)
         m_range.end = std::max(m_range.end, atom.end());
     }
     m_atoms.push_back(std::move(atom));
+    return m_atoms.back();
 }
 
 DisplayLine::iterator DisplayLine::erase(iterator beg, iterator end)
diff --git a/src/display_buffer.hh b/src/display_buffer.hh
index ec5da89e..6d739095 100644
--- a/src/display_buffer.hh
+++ b/src/display_buffer.hh
@@ -142,7 +142,7 @@ public:
     }
 
     iterator erase(iterator beg, iterator end);
-    void push_back(DisplayAtom atom);
+    DisplayAtom& push_back(DisplayAtom atom);
 
     // remove first_col from the begining of the line, and make sure
     // the line is less that col_count character
diff --git a/src/highlighters.cc b/src/highlighters.cc
index 3f60721e..6d370aae 100644
--- a/src/highlighters.cc
+++ b/src/highlighters.cc
@@ -647,8 +647,12 @@ std::unique_ptr<Highlighter> create_column_highlighter(HighlighterParameters par
             auto remaining_col = column;
             bool found = false;
             auto first_buf = find_if(line, [](auto& atom) { return atom.has_buffer_range(); });
+            BufferCoord last_pos{};
             for (auto atom_it = first_buf; atom_it != line.end(); ++atom_it)
             {
+                if (atom_it->has_buffer_range())
+                    last_pos = atom_it->end();
+
                 const auto atom_len = atom_it->length();
                 if (remaining_col < atom_len)
                 {
@@ -666,8 +670,8 @@ std::unique_ptr<Highlighter> create_column_highlighter(HighlighterParameters par
                 continue;
 
             if (remaining_col > 0)
-                line.push_back({buffer, buffer.end_coord(), buffer.end_coord(), String{' ', remaining_col}});
-            line.push_back({" ", face});
+                line.push_back({buffer, last_pos, last_pos, String{' ', remaining_col}});
+            line.push_back({buffer, last_pos, last_pos, " "}).face = face;
         }
     };