Wire up config infrastructure for diff kitten

kittens/diff/config.py

@@ -2,8 +2,78 @@
 # vim:fileencoding=utf-8
 # License: GPL v3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
 
+import os
+
+from kitty.config_utils import (
+    init_config, load_config as _load_config, merge_dicts, parse_config_base,
+    resolve_config, to_color
+)
+from kitty.constants import config_dir
+
+defaults = None
+default_config_path = os.path.join(
+    os.path.dirname(os.path.abspath(__file__)), 'diff.conf'
+)
+
 formats = {
     'title': '',
     'margin': '',
     'text': '',
 }
+
+type_map = {}
+
+for name in (
+    'foreground background'
+).split():
+    type_map[name] = to_color
+
+
+def special_handling(*a):
+    pass
+
+
+def parse_config(lines, check_keys=True):
+    ans = {}
+    parse_config_base(
+        lines,
+        defaults,
+        type_map,
+        special_handling,
+        ans,
+        check_keys=check_keys
+    )
+    return ans
+
+
+def merge_configs(defaults, vals):
+    ans = {}
+    for k, v in defaults.items():
+        if isinstance(v, dict):
+            newvals = vals.get(k, {})
+            ans[k] = merge_dicts(v, newvals)
+        else:
+            ans[k] = vals.get(k, v)
+    return ans
+
+
+def parse_defaults(lines, check_keys=False):
+    return parse_config(lines, check_keys)
+
+
+Options, defaults = init_config(default_config_path, parse_defaults)
+
+
+def load_config(*paths, overrides=None):
+    return _load_config(Options, defaults, parse_config, merge_configs, *paths, overrides=overrides)
+
+
+SYSTEM_CONF = '/etc/xdg/kitty/diff.conf'
+defconf = os.path.join(config_dir, 'diff.conf')
+
+
+def init_config(args):
+    config = tuple(resolve_config(SYSTEM_CONF, defconf, args.config))
+    overrides = (a.replace('=', ' ', 1) for a in args.override or ())
+    opts = load_config(*config, overrides=overrides)
+    return opts