From a9d33a879696818b556fab00080fcabb8a120db9 Mon Sep 17 00:00:00 2001
From: nojhan <nojhan@nojhan.net>
Date: Tue, 27 Apr 2021 15:27:57 +0200
Subject: [PATCH] fix ncurses' padding option

- Use less iterations when drawing padding fill with multiple characters.
- Use column_length to handle null-width character as no character.
---
 src/ncurses_ui.cc | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/ncurses_ui.cc b/src/ncurses_ui.cc
index d2d93b0e..86fcedec 100644
--- a/src/ncurses_ui.cc
+++ b/src/ncurses_ui.cc
@@ -477,8 +477,11 @@ void NCursesUI::draw(const DisplayBuffer& display_buffer,
         if (m_padding_fill)
         {
             ColumnCount column_index = 0;
-            while (column_index++ < dim.column)
+            while (column_index < dim.column)
+            {
                 m_window.draw(m_palette, m_padding_char, face);
+                column_index += m_padding_char.length();
+            }
         }
         else
             m_window.draw(m_palette, m_padding_char, face);
@@ -1372,8 +1375,10 @@ void NCursesUI::set_ui_options(const Options& options)
     {
         auto it = options.find("ncurses_padding_char"_sv);
         if (it == options.end())
+            // Defaults to tilde.
             m_padding_char = DisplayAtom("~");
-        else if (it->value.length() < 1)
+        else if (it->value.column_length() < 1)
+            // Do not allow empty string, use space instead.
             m_padding_char = DisplayAtom(" ");
         else
             m_padding_char = DisplayAtom(it->value);