Set console font automatically when selecting language (#4356)

* Set console font automatically when selecting language

Add console_font field to languages.json and Language dataclass.
When a language is activated, setfont is called automatically,
falling back to default8x16 on error or for languages without
a custom font. Also activate translation when loading language
from config file.

* Support FONT environment variable for console font override

When FONT env var is set, use it as the console font instead of the language-specific font mapping from languages.json. The font is applied at startup and preserved across language switches.

On exit (success or failure), restore the console font to default8x16.

* CI checks fix

* Try to restore original console font with setfont -O

* Fix for pylint

* Restore console font before Textual exits application mode

Move font set/restore into Textual lifecycle to prevent color
artifacts from 256/512 glyph transitions. Apply FONT env var
and language font in on_mount, restore in _on_exit_app.

Skip font change when loading language from config (set_font=False)
to defer it until TUI starts.

* Fall back to language font mapping when FONT env var is invalid

Add _using_env_font flag to skip mapping only when FONT was
successfully applied. Show info message after TUI exits if FONT
could not be set.

* Use tempfile for console font backup files

* Fix linter errors: use mkstemp, close fds, add @override

* Fix ruff formatting

* Move font state from module singleton into TranslationHandler

* Refactor font handling per review feedback

* Make font methods members of TranslationHandler, skip on non-ISO

* ci: trigger tests

* Move running_from_iso import to module level

No circular dep, simpler than per-method local imports.

* Add explicit ISO guard to restore_console_font

Matches the existing guards in _set_font and save_console_font.
Behaviour was already safe implicitly via _font_backup=None, but
the explicit check makes intent obvious at the call site.

* Skip apply_console_font off-ISO

* Use list form for setfont SysCommand calls

archinstall/lib/args.py

@@ -143,6 +143,7 @@ class ArchConfig:
 
 		if archinstall_lang := args_config.get('archinstall-language', None):
 			arch_config.archinstall_language = translation_handler.get_language_by_name(archinstall_lang)
+			translation_handler.activate(arch_config.archinstall_language, set_font=False)
 
 		if disk_config := args_config.get('disk_config', {}):
 			enc_password = args_config.get('encryption_password', '')

archinstall/lib/general/general_menu.py

@@ -105,9 +105,9 @@ async def select_archinstall_language(languages: list[Language], preset: Languag
 	group = MenuItemGroup(items, sort_items=True)
 	group.set_focus_by_value(preset)
 
-	title = 'NOTE: If a language can not displayed properly, a proper font must be set manually in the console.\n'
-	title += 'All available fonts can be found in "/usr/share/kbd/consolefonts"\n'
-	title += 'e.g. setfont LatGrkCyr-8x16 (to display latin/greek/cyrillic characters)\n'
+	title = 'NOTE: Console font will be set automatically for supported languages.\n'
+	title += 'For other languages, fonts can be found in "/usr/share/kbd/consolefonts"\n'
+	title += 'and set manually with: setfont <fontname>\n'
 
 	result = await Selection[Language](
 		header=title,

archinstall/lib/translationhandler.py

@@ -2,10 +2,16 @@ import builtins
 import gettext
 import json
 import os
+import tempfile
 from dataclasses import dataclass
 from pathlib import Path
 from typing import override
 
+from archinstall.lib.command import SysCommand
+from archinstall.lib.exceptions import SysCallError
+from archinstall.lib.output import debug
+from archinstall.lib.utils.util import running_from_iso
+
 
 @dataclass
 class Language:
@@ -14,6 +20,7 @@ class Language:
 	translation: gettext.NullTranslations
 	translation_percent: int
 	translated_lang: str | None
+	console_font: str | None = None
 
 	@property
 	def display_name(self) -> str:
@@ -31,10 +38,18 @@ class Language:
 		return self.name_en
 
 
+_DEFAULT_FONT = 'default8x16'
+_ENV_FONT = os.environ.get('FONT')
+
+
 class TranslationHandler:
 	def __init__(self) -> None:
 		self._base_pot = 'base.pot'
 		self._languages = 'languages.json'
+		self._active_language: Language | None = None
+		self._font_backup: Path | None = None
+		self._cmap_backup: Path | None = None
+		self._using_env_font: bool = False
 
 		self._total_messages = self._get_total_active_messages()
 		self._translated_languages = self._get_translations()
@@ -43,6 +58,65 @@ class TranslationHandler:
 	def translated_languages(self) -> list[Language]:
 		return self._translated_languages
 
+	@property
+	def active_font(self) -> str | None:
+		if self._active_language is not None:
+			return self._active_language.console_font
+		return None
+
+	def _set_font(self, font_name: str | None) -> bool:
+		"""Set the console font via setfont. Only runs on ISO. Returns True on success."""
+		if not running_from_iso():
+			return False
+
+		target = font_name or _DEFAULT_FONT
+		try:
+			SysCommand(['setfont', target])
+			return True
+		except SysCallError as err:
+			debug(f'Failed to set console font {target}: {err}')
+			return False
+
+	def save_console_font(self) -> None:
+		"""Save the current console font (with unicode map) and console map to temp files."""
+		if not running_from_iso():
+			return
+
+		try:
+			font_fd, font_path = tempfile.mkstemp(prefix='archinstall_font_')
+			cmap_fd, cmap_path = tempfile.mkstemp(prefix='archinstall_cmap_')
+			os.close(font_fd)
+			os.close(cmap_fd)
+			self._font_backup = Path(font_path)
+			self._cmap_backup = Path(cmap_path)
+			SysCommand(['setfont', '-O', str(self._font_backup), '-om', str(self._cmap_backup)])
+		except SysCallError as err:
+			debug(f'Failed to save console font: {err}')
+			self._font_backup = None
+			self._cmap_backup = None
+
+	def restore_console_font(self) -> None:
+		"""Restore console font (with unicode map) and console map from backup."""
+		if not running_from_iso():
+			return
+
+		if self._font_backup is None or not self._font_backup.exists():
+			return
+
+		cmd = ['setfont', str(self._font_backup)]
+		if self._cmap_backup is not None and self._cmap_backup.exists():
+			cmd += ['-m', str(self._cmap_backup)]
+		try:
+			SysCommand(cmd)
+		except SysCallError as err:
+			debug(f'Failed to restore console font: {err}')
+
+		self._font_backup.unlink(missing_ok=True)
+		self._font_backup = None
+		if self._cmap_backup is not None:
+			self._cmap_backup.unlink(missing_ok=True)
+			self._cmap_backup = None
+
 	def _get_translations(self) -> list[Language]:
 		"""
 		Load all translated languages and return a list of such
@@ -57,6 +131,7 @@ class TranslationHandler:
 			abbr = mapping_entry['abbr']
 			lang = mapping_entry['lang']
 			translated_lang = mapping_entry.get('translated_lang', None)
+			console_font = mapping_entry.get('console_font', None)
 
 			try:
 				# get a translation for a specific language
@@ -71,7 +146,7 @@ class TranslationHandler:
 					# prevent cases where the .pot file is out of date and the percentage is above 100
 					percent = min(100, percent)
 
-				language = Language(abbr, lang, translation, percent, translated_lang)
+				language = Language(abbr, lang, translation, percent, translated_lang, console_font)
 				languages.append(language)
 			except FileNotFoundError as err:
 				raise FileNotFoundError(f"Could not locate language file for '{lang}': {err}")
@@ -127,12 +202,39 @@ class TranslationHandler:
 		except Exception:
 			raise ValueError(f'No language with abbreviation "{abbr}" found')
 
-	def activate(self, language: Language) -> None:
+	def activate(self, language: Language, set_font: bool = True) -> None:
 		"""
 		Set the provided language as the current translation
 		"""
 		# The install() call has the side effect of assigning GNUTranslations.gettext to builtins._
 		language.translation.install()
+		self._active_language = language
+
+		if set_font and not self._using_env_font:
+			self._set_font(language.console_font)
+
+	def apply_console_font(self) -> None:
+		"""Apply console font from FONT env var or active language mapping.
+
+		If FONT env var is set and valid, use it and skip language mapping.
+		If FONT is set but invalid, fall back to language font.
+		If FONT is not set, use active language font.
+		"""
+		if not running_from_iso():
+			return
+
+		if _ENV_FONT:
+			if self._set_font(_ENV_FONT):
+				self._using_env_font = True
+				debug(f'Console font set from FONT env var: {_ENV_FONT}')
+			else:
+				debug(f'FONT={_ENV_FONT} could not be set, falling back to language font mapping')
+				if self.active_font:
+					self._set_font(self.active_font)
+					debug(f'Console font set from language mapping: {self.active_font}')
+		elif self.active_font:
+			self._set_font(self.active_font)
+			debug(f'Console font set from language mapping: {self.active_font}')
 
 	def _get_locales_dir(self) -> Path:
 		"""

archinstall/locales/languages.json

@@ -169,7 +169,7 @@
  {"abbr": "tr", "lang": "Turkish", "translated_lang" :  "Türkçe"},
  {"abbr": "tw", "lang": "Twi"},
  {"abbr": "ug", "lang": "Uighur"},
- {"abbr": "uk", "lang": "Ukrainian"},
+ {"abbr": "uk", "lang": "Ukrainian", "console_font": "UniCyr_8x16"},
  {"abbr": "ur", "lang": "Urdu", "translated_lang": "اردو"},
  {"abbr": "uz", "lang": "Uzbek", "translated_lang": "O'zbek"},
  {"abbr": "ve", "lang": "Venda"},

archinstall/main.py

@@ -16,7 +16,7 @@ from archinstall.lib.networking import ping
 from archinstall.lib.output import debug, error, info, warn
 from archinstall.lib.packages.util import check_version_upgrade
 from archinstall.lib.pacman.pacman import Pacman
-from archinstall.lib.translationhandler import tr
+from archinstall.lib.translationhandler import tr, translation_handler
 from archinstall.lib.utils.util import running_from_iso
 from archinstall.tui.ui.components import tui
 
@@ -95,6 +95,8 @@ def run() -> int:
 		print(tr('Archinstall requires root privileges to run. See --help for more.'))
 		return 1
 
+	translation_handler.save_console_font()
+
 	_log_sys_info()
 
 	if not arch_config_handler.args.offline:
@@ -159,6 +161,8 @@ def main() -> int:
 			_error_message(exc)
 			rc = 1
 
+		translation_handler.restore_console_font()
+
 	return rc
 
 

archinstall/tui/ui/components.py

@@ -1272,6 +1272,13 @@ class _AppInstance(App[ValueT]):
 		super().__init__(ansi_color=True)
 		self._main = main
 
+	@override
+	async def _on_exit_app(self) -> None:
+		from archinstall.lib.translationhandler import translation_handler
+
+		translation_handler.restore_console_font()
+		await super()._on_exit_app()
+
 	def action_trigger_help(self) -> None:
 		from textual.widgets import HelpPanel
 
@@ -1281,6 +1288,9 @@ class _AppInstance(App[ValueT]):
 			_ = self.screen.mount(HelpPanel())
 
 	def on_mount(self) -> None:
+		from archinstall.lib.translationhandler import translation_handler
+
+		translation_handler.apply_console_font()
 		_translate_bindings(self._merged_bindings, self._bindings)
 		self._run_worker()