From c92aca5d1901d176ea88c3c9e0c16f94f27a7f6e Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 24 Apr 2020 19:45:51 +0530
Subject: [PATCH] Use a Literal as the type for choice based options

---
 kitty/conf/definition.py |  4 +++-
 kitty/conf/utils.py      | 18 +++++++++++-------
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/kitty/conf/definition.py b/kitty/conf/definition.py
index 3c1e77757..a858e34ff 100644
--- a/kitty/conf/definition.py
+++ b/kitty/conf/definition.py
@@ -9,7 +9,7 @@ from typing import (
     Set, Tuple, Union, get_type_hints
 )
 
-from .utils import to_bool
+from .utils import Choice, to_bool
 
 
 def to_string(x: str) -> str:
@@ -56,6 +56,8 @@ class Option:
 
         if type(self.option_type) is type:
             return type_name(self.option_type)
+        if isinstance(self.option_type, Choice):
+            return 'typing.Literal[{}]'.format(','.join(f'{x!r}' for x in self.option_type.all_choices))
         th = get_type_hints(self.option_type)
         try:
             rettype = th['return']
diff --git a/kitty/conf/utils.py b/kitty/conf/utils.py
index e007c175d..9bc0134e5 100644
--- a/kitty/conf/utils.py
+++ b/kitty/conf/utils.py
@@ -68,17 +68,21 @@ def python_string(text: str) -> str:
     return ans
 
 
-def choices(*choices: str) -> Callable[[str], str]:
-    defval = choices[0]
-    uc = frozenset(choices)
+class Choice:
 
-    def choice(x: str) -> str:
+    def __init__(self, choices: Sequence[str]):
+        self.defval = choices[0]
+        self.all_choices = frozenset(choices)
+
+    def __call__(self, x: str) -> str:
         x = x.lower()
-        if x not in uc:
-            x = defval
+        if x not in self.all_choices:
+            x = self.defval
         return x
 
-    return choice
+
+def choices(*choices: str) -> Choice:
+    return Choice(choices)
 
 
 def parse_line(