From ad1ff455a0e999916eeb9641ce18aeffaa620e22 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 27 Apr 2020 16:17:05 +0530
Subject: [PATCH] macOS: Fix a regression in the previous release that caused
 ligatures to be not be centered horizontally

Fixes #2591
---
 docs/changelog.rst |  8 ++++++++
 kitty/fonts.c      | 15 +++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/docs/changelog.rst b/docs/changelog.rst
index fdb107fd3..fd0931c0e 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -4,6 +4,14 @@ Changelog
 |kitty| is a feature full, cross-platform, *fast*, GPU based terminal emulator.
 To update |kitty|, :doc:`follow the instructions <binary>`.
 
+
+0.17.4 [future]
+--------------------
+
+- macOS: Fix a regression in the previous release that caused ligatures to be
+  not be centered horizontally (:iss:`2591`)
+
+
 0.17.3 [2020-04-23]
 --------------------
 
diff --git a/kitty/fonts.c b/kitty/fonts.c
index d35dc902a..b6c4c7b9a 100644
--- a/kitty/fonts.c
+++ b/kitty/fonts.c
@@ -1004,14 +1004,20 @@ merge_groups_for_pua_space_ligature(void) {
     G(groups)->is_space_ligature = true;
 }
 
+static inline bool
+is_group_calt_ligature(const Group *group) {
+    GPUCell *first_cell = G(first_gpu_cell) + group->first_cell_idx;
+    return group->num_cells > 1 && group->has_special_glyph && (first_cell->attrs & WIDTH_MASK) == 1;
+}
+
+
 static inline void
 split_run_at_offset(index_type cursor_offset, index_type *left, index_type *right) {
     *left = 0; *right = 0;
     for (unsigned idx = 0; idx < G(group_idx) + 1; idx++) {
         Group *group = G(groups) + idx;
         if (group->first_cell_idx <= cursor_offset && cursor_offset < group->first_cell_idx + group->num_cells) {
-            GPUCell *first_cell = G(first_gpu_cell) + group->first_cell_idx;
-            if (group->num_cells > 1 && group->has_special_glyph && (first_cell->attrs & WIDTH_MASK) == 1) {
+            if (is_group_calt_ligature(group)) {
                 // likely a calt ligature
                 *left = group->first_cell_idx; *right = group->first_cell_idx + group->num_cells;
             }
@@ -1039,6 +1045,11 @@ render_groups(FontGroup *fg, Font *font, bool center_glyph) {
         // there exist stupid fonts like Powerline that have no space glyph,
         // so special case it: https://github.com/kovidgoyal/kitty/issues/1225
         unsigned int num_glyphs = group->is_space_ligature ? 1 : group->num_glyphs;
+#ifdef __APPLE__
+        // FiraCode ligatures need to be centered on macOS
+        // see https://github.com/kovidgoyal/kitty/issues/2591
+        if (is_group_calt_ligature(group)) center_glyph = true;
+#endif
         render_group(fg, group->num_cells, num_glyphs, G(first_cpu_cell) + group->first_cell_idx, G(first_gpu_cell) + group->first_cell_idx, G(info) + group->first_glyph_idx, G(positions) + group->first_glyph_idx, font, primary, &ed, center_glyph);
         idx++;
     }