From 0b9a37139e26b294547c21a9c564348955faa81c Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 6 Apr 2020 23:00:34 +0530
Subject: [PATCH] Render any flag pair in two cells not just known ones

---
 gen-wcwidth.py | 18 +-----------------
 kitty/emoji.h  | 32 --------------------------------
 kitty/screen.c |  5 ++++-
 3 files changed, 5 insertions(+), 50 deletions(-)

diff --git a/gen-wcwidth.py b/gen-wcwidth.py
index 8a45e4d99..ec4c67ce3 100755
--- a/gen-wcwidth.py
+++ b/gen-wcwidth.py
@@ -10,7 +10,7 @@ from contextlib import contextmanager
 from datetime import date
 from functools import partial
 from html.entities import html5
-from itertools import groupby, repeat
+from itertools import groupby
 from operator import itemgetter
 from typing import (
     Callable, DefaultDict, Dict, FrozenSet, Generator, Iterable, List,
@@ -266,22 +266,6 @@ def gen_emoji() -> None:
         p('\t}')
         p('\treturn false;\n}')
 
-        p('static inline bool is_flag_pair(char_type a, char_type b) {')
-        p('static const unsigned char flag_combinations[26][26] = {')
-        for i in range(26):
-            q = 0x1F1E6 + i
-            vals = flags.get(q, [])
-            arr = list(repeat(0, 26))
-            for x in vals:
-                idx = x - 0x1F1E6
-                arr[idx] = 1
-            comma = '' if i == 0 else ','
-            p(comma, '{', ', '.join(map(str, arr)), '}')
-        p('};')
-        p('if (a < 0x1F1E6 || b < 0x1F1E6 || a >= 0x1F1E6 + 26 || b >= 0x1F1E6 + 26) return false;')
-        p('return flag_combinations[a - 0x1F1E6][b - 0x1F1E6];')
-        p('};')
-
 
 def category_test(
     name: str,
diff --git a/kitty/emoji.h b/kitty/emoji.h
index 8bb04f521..a3e6f1f97 100644
--- a/kitty/emoji.h
+++ b/kitty/emoji.h
@@ -781,37 +781,5 @@ is_symbol(char_type code) {
 	}
 	return false;
 }
-static inline bool is_flag_pair(char_type a, char_type b) {
-static const unsigned char flag_combinations[26][26] = {
- { 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1 }
-, { 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1 }
-, { 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1 }
-, { 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 }
-, { 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0 }
-, { 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0 }
-, { 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0 }
-, { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0 }
-, { 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0 }
-, { 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
-, { 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1 }
-, { 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 0 }
-, { 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 }
-, { 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1 }
-, { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
-, { 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0 }
-, { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
-, { 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0 }
-, { 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1 }
-, { 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1 }
-, { 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1 }
-, { 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0 }
-, { 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 }
-, { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
-, { 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0 }
-, { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0 }
-};
-if (a < 0x1F1E6 || b < 0x1F1E6 || a >= 0x1F1E6 + 26 || b >= 0x1F1E6 + 26) return false;
-return flag_combinations[a - 0x1F1E6][b - 0x1F1E6];
-};
 
 END_ALLOW_CASE_RANGE
diff --git a/kitty/screen.c b/kitty/screen.c
index 28ee6824a..c28fe5066 100644
--- a/kitty/screen.c
+++ b/kitty/screen.c
@@ -14,7 +14,6 @@
 #include "fonts.h"
 #include "lineops.h"
 #include "screen.h"
-#include "emoji.h"
 #include <structmember.h>
 #include <limits.h>
 #include <sys/types.h>
@@ -358,6 +357,10 @@ selection_has_screen_line(Selection *s, int y) {
     return top <= y && y <= bottom;
 }
 
+static inline bool is_flag_pair(char_type a, char_type b) {
+    return is_flag_codepoint(a) && is_flag_codepoint(b);
+}
+
 static inline bool
 draw_second_flag_codepoint(Screen *self, char_type ch) {
     index_type xpos = 0, ypos = 0;