[vte] draw: Do not cache ligatured glyphs

[Egmont Koblinger <egmontkob src gnome org>]

commit b398e253053806a05261aca79d6cfbfa9d69ed9b
Author: Egmont Koblinger <egmont gmail com>
Date:   Sat Mar 3 17:42:34 2018 +0100

    draw: Do not cache ligatured glyphs
    
    This workaround avoids ligatured glyphs (e.g. for "<=>") from being cached.
    A more proper solution is still pending.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=793391

 src/vtedraw.cc |   15 ++++++++-------
 1 files changed, 8 insertions(+), 7 deletions(-)
---
diff --git a/src/vtedraw.cc b/src/vtedraw.cc
index 37d324c..178f844 100644
--- a/src/vtedraw.cc
+++ b/src/vtedraw.cc
@@ -32,14 +32,15 @@
 
 #include <pango/pangocairo.h>
 
+/* Have a space between letters to make sure ligatures aren't used when caching the glyphs: bug 793391. */
 #define VTE_DRAW_SINGLE_WIDE_CHARACTERS        \
-                                       " !\"#$%&'()*+,-./" \
-                                       "0123456789" \
-                                       ":;<=>?@" \
-                                       "ABCDEFGHIJKLMNOPQRSTUVWXYZ" \
-                                       "[\\]^_`" \
-                                       "abcdefghijklmnopqrstuvwxyz" \
-                                       "{|}~" \
+                                       "  ! \" # $ % & ' ( ) * + , - . / " \
+                                       "0 1 2 3 4 5 6 7 8 9 " \
+                                       ": ; < = > ? @ " \
+                                       "A B C D E F G H I J K L M N O P Q R S T U V W X Y Z " \
+                                       "[ \\ ] ^ _ ` " \
+                                       "a b c d e f g h i j k l m n o p q r s t u v w x y z " \
+                                       "{ | } ~ " \
                                        ""
 
 static inline bool