Linux: Fix match rules used as aliases in Fontconfig configuration not being respected

Fixes #1085

docs/changelog.rst

@@ -27,11 +27,14 @@ Changelog
 
 - macOS: Fix drag and drop of files not working on mojave (:iss:`1058`)
 
-- macOS: Fix IME input for east asian languages (:iss:`910`)
+- macOS: Fix IME input for East Asian languages (:iss:`910`)
 
 - macOS: Fix rendering frames-per-second very low when processing
   large amounts of input in small chunks (:pull:`1082`)
 
+- Linux: Fix match rules used as aliases in Fontconfig configuration not being
+  respected (:iss:`1085`)
+
 - Fix expansion of env vars not working in the :opt:`env` directive
   (:iss:`1075`)
 

kitty/fonts/fontconfig.py

@@ -44,8 +44,12 @@ def list_fonts():
             yield {'family': f, 'full_name': fn, 'is_monospace': is_mono}
 
 
+def family_name_to_key(family):
+    return re.sub(r'\s+', ' ', family.lower())
+
+
 def find_best_match(family, bold=False, italic=False, monospaced=True):
-    q = re.sub(r'\s+', ' ', family.lower())
+    q = family_name_to_key(family)
     font_map = all_fonts_map(monospaced)
 
     def score(candidate):
@@ -61,6 +65,16 @@ def find_best_match(family, bold=False, italic=False, monospaced=True):
             candidates.sort(key=score)
             return candidates[0]
 
+    # Use fc-match to see if we can find a monospaced font that matches family
+    possibility = fc_match(family, False, False)
+    for key, map_key in (('postscript_name', 'ps_map'), ('full_name', 'full_map'), ('family', 'family_map')):
+        val = possibility.get(key)
+        if val:
+            candidates = font_map[map_key].get(family_name_to_key(val))
+            if candidates:
+                candidates.sort(key=score)
+                return candidates[0]
+
     # Use fc-match with a generic family
     family = 'monospace' if monospaced else 'sans-serif'
     return fc_match(family, bold, italic)