Nicer fix for #8124

Now colors from the auto themes are first merged onto the default colors
to ensure that themes that dont specify all colors still have correct
values for all colors.

docs/changelog.rst

@@ -90,7 +90,9 @@ Detailed list of changes
 
 - macOS: Fix a regression in the previous release that broke rendering of Emoji using the VS16 variation selector (:iss:`8130`)
 
-- themes kitten: When using the *Default* theme as an auto switch theme include all the actual settings values (:iss:`8124`)
+- When automatically changing colors based on OS color preference, first reset
+  all colors to default before applying the new theme so that even colors not
+  specified in the theme are correct (:iss:`8124`)
 
 - Graphics: Fix deleted but not freed images without any references being incorrectly freed on a subsequent delete command (:disc:`8129`)
 

kitty/colors.py

@@ -16,6 +16,7 @@
 ColorsSpec = dict[str, Optional[int]]
 TransparentBackgroundColors = tuple[tuple[Color, float], ...]
 ColorSchemes = Literal['light', 'dark', 'no_preference']
+Colors = tuple[ColorsSpec, TransparentBackgroundColors]
 
 
 class ThemeFile(Enum):
@@ -30,6 +31,29 @@ class ThemeColors:
     light_mtime: int = -1
     no_preference_mtime: int = -1
     applied_theme: Literal['light', 'dark', 'no_preference', ''] = ''
+    default_colors: Optional[ColorsSpec] = None
+
+    def get_default_colors(self) -> ColorsSpec:
+        if self.default_colors is None:
+            from kitty.options.types import defaults, option_names
+            ans: ColorsSpec = dict.fromkeys(nullable_colors)
+
+            for name in option_names:
+                defval = getattr(defaults, name)
+                if isinstance(defval, Color):
+                    ans[name] = int(defval)
+            self.default_colors = ans
+        return self.default_colors
+
+    def parse_colors(self, f: Iterable[str]) -> Colors:
+        # When parsing the theme file we first apply the default theme so that
+        # all colors are reset to default values first. This is needed for themes
+        # that don't specify all colors.
+        spec, tbc = parse_colors((f,))
+        dc_spec = self.get_default_colors()
+        ans = dc_spec.copy()
+        ans.update(spec)
+        return ans, tbc
 
     def refresh(self) -> bool:
         found = False
@@ -39,21 +63,21 @@ def refresh(self) -> bool:
                     mtime = x.stat().st_mtime_ns
                     if mtime > self.dark_mtime:
                         with open(x.path) as f:
-                            self.dark_spec, self.dark_tbc = parse_colors((f,))
+                            self.dark_spec, self.dark_tbc = self.parse_colors(f)
                         self.dark_mtime = mtime
                         found = True
                 elif x.name == ThemeFile.light.value:
                     mtime = x.stat().st_mtime_ns
                     if mtime > self.light_mtime:
                         with open(x.path) as f:
-                            self.light_spec, self.light_tbc = parse_colors((f,))
+                            self.light_spec, self.light_tbc = self.parse_colors(f)
                         self.light_mtime = mtime
                         found = True
                 elif x.name == ThemeFile.no_preference.value:
                     mtime = x.stat().st_mtime_ns
                     if mtime > self.no_preference_mtime:
                         with open(x.path) as f:
-                            self.no_preference_spec, self.no_preference_tbc = parse_colors((f,))
+                            self.no_preference_spec, self.no_preference_tbc = self.parse_colors(f)
                         self.no_preference_mtime = mtime
                         found = True
         return found
@@ -123,7 +147,7 @@ def on_system_color_scheme_change(self, new_value: ColorSchemes, is_initial_valu
 theme_colors = ThemeColors()
 
 
-def parse_colors(args: Iterable[Union[str, Iterable[str]]]) -> tuple[ColorsSpec, TransparentBackgroundColors]:
+def parse_colors(args: Iterable[Union[str, Iterable[str]]]) -> Colors:
     colors: dict[str, Optional[Color]] = {}
     nullable_color_map: dict[str, Optional[int]] = {}
     transparent_background_colors = ()