Extract argument parsing to a file

src/textual_paint/args.py

@@ -0,0 +1,76 @@
+"""Command line arguments for the app."""
+
+import argparse
+import os
+import re
+
+from .__init__ import __version__
+
+parser = argparse.ArgumentParser(description='Paint in the terminal.', usage='%(prog)s [options] [filename]', prog="textual-paint")
+parser.add_argument('--version', action='version', version=f'%(prog)s {__version__}')
+parser.add_argument('--theme', default='light', help='Theme to use, either "light" or "dark"', choices=['light', 'dark'])
+parser.add_argument('--language', default='en', help='Language to use', choices=['ar', 'cs', 'da', 'de', 'el', 'en', 'es', 'fi', 'fr', 'he', 'hu', 'it', 'ja', 'ko', 'nl', 'no', 'pl', 'pt', 'pt-br', 'ru', 'sk', 'sl', 'sv', 'tr', 'zh', 'zh-simplified'])
+parser.add_argument('--ascii-only-icons', action='store_true', help='Use only ASCII characters for tool icons, no emoji or other Unicode symbols')
+parser.add_argument('--ascii-only', action='store_true', help='Use only ASCII characters for the entire UI, for use in older terminals. Implies --ascii-only-icons')
+parser.add_argument('--backup-folder', default=None, metavar="FOLDER", help='Folder to save backups to. By default a backup is saved alongside the edited file.')
+
+# TODO: hide development options from help? there's quite a few of them now
+parser.add_argument('--inspect-layout', action='store_true', help='Enables DOM inspector (F12) and middle click highlight, for development')
+# This flag is for development, because it's very confusing
+# to see the error message from the previous run,
+# when a problem is actually solved.
+# There are enough ACTUAL "that should have worked!!" moments to deal with.
+# I really don't want false ones mixed in. You want to reward your brain for finding good solutions, after all.
+parser.add_argument('--clear-screen', action='store_true', help='Clear the screen before starting; useful for development, to avoid seeing outdated errors')
+parser.add_argument('--restart-on-changes', action='store_true', help='Restart the app when the source code is changed, for development')
+parser.add_argument('--recode-samples', action='store_true', help='Open and save each file in samples/, for testing')
+
+parser.add_argument('filename', nargs='?', default=None, help='Path to a file to open. File will be created if it doesn\'t exist.')
+
+def update_cli_help_on_readme():
+    """Update the readme with the current CLI usage info"""
+    readme_help_start = re.compile(r"```\n.*--help\n")
+    readme_help_end = re.compile(r"```")
+    readme_file_path = os.path.join(os.path.dirname(__file__), "../../README.md")
+    with open(readme_file_path, "r+", encoding="utf-8") as f:
+        # By default, argparse uses the terminal width for formatting help text,
+        # even when using format_help() to get a string.
+        # The only way to override that is to override the formatter_class.
+        # This is hacky, but it seems like the simplest way to fix the width
+        # without creating a separate ArgumentParser, and without breaking the wrapping for --help.
+        # This lambda works because python uses the same syntax for construction and function calls,
+        # so formatter_class doesn't need to be an actual class.
+        # See: https://stackoverflow.com/questions/44333577/explain-lambda-argparse-helpformatterprog-width
+        width = 80
+        old_formatter_class = parser.formatter_class
+        parser.formatter_class = lambda prog: argparse.HelpFormatter(prog, width=width)
+        help_text = parser.format_help()
+        parser.formatter_class = old_formatter_class
+        
+        md = f.read()
+        start_match = readme_help_start.search(md)
+        if start_match is None:
+            raise Exception("Couldn't find help section in readme")
+        start = start_match.end()
+        end_match = readme_help_end.search(md, start)
+        if end_match is None:
+            raise Exception("Couldn't find end of help section in readme")
+        end = end_match.start()
+        md = md[:start] + help_text + md[end:]
+        f.seek(0)
+        f.write(md)
+        f.truncate()
+# Manually disabled for release.
+# TODO: disable for release builds, while keeping it automatic during development.
+# (I could make this another dev flag, but I like the idea of it being automatic.)
+# (Maybe a pre-commit hook would be ideal, if it's worth the complexity.)
+# update_cli_help_on_readme()
+
+args = parser.parse_args()
+"""Parsed command line arguments."""
+
+def get_help_text() -> str:
+    """Get the help text for the command line arguments."""
+    return parser.format_help()
+
+__all__ = ["args", "get_help_text"]

src/textual_paint/paint.py

@@ -7,7 +7,6 @@ import os
 from pathlib import Path
 import re
 import shlex
-import argparse
 import asyncio
 from enum import Enum
 from random import randint, random
@@ -57,6 +56,7 @@ from .localization.i18n import get as _, load_language, remove_hotkey
 from .rasterize_ansi_art import rasterize
 from .wallpaper import get_config_dir, set_wallpaper
 from .auto_restart import restart_on_changes, restart_program
+from .args import args, get_help_text
 
 from .__init__ import __version__
 
@@ -69,72 +69,10 @@ DEBUG_SVG_LOADING = False # writes debug.svg when flexible character grid loader
 # ICNS is disabled because it only supports a limited set of sizes.
 SAVE_DISABLED_FORMATS = ["JPEG", "ICNS"]
 
-# Command line arguments
-parser = argparse.ArgumentParser(description='Paint in the terminal.', usage='%(prog)s [options] [filename]', prog="textual-paint")
-parser.add_argument('--version', action='version', version=f'%(prog)s {__version__}')
-parser.add_argument('--theme', default='light', help='Theme to use, either "light" or "dark"', choices=['light', 'dark'])
-parser.add_argument('--language', default='en', help='Language to use', choices=['ar', 'cs', 'da', 'de', 'el', 'en', 'es', 'fi', 'fr', 'he', 'hu', 'it', 'ja', 'ko', 'nl', 'no', 'pl', 'pt', 'pt-br', 'ru', 'sk', 'sl', 'sv', 'tr', 'zh', 'zh-simplified'])
-parser.add_argument('--ascii-only-icons', action='store_true', help='Use only ASCII characters for tool icons, no emoji or other Unicode symbols')
-parser.add_argument('--ascii-only', action='store_true', help='Use only ASCII characters for the entire UI, for use in older terminals. Implies --ascii-only-icons')
-parser.add_argument('--backup-folder', default=None, metavar="FOLDER", help='Folder to save backups to. By default a backup is saved alongside the edited file.')
-
-# TODO: hide development options from help? there's quite a few of them now
-parser.add_argument('--inspect-layout', action='store_true', help='Enables DOM inspector (F12) and middle click highlight, for development')
-# This flag is for development, because it's very confusing
-# to see the error message from the previous run,
-# when a problem is actually solved.
-# There are enough ACTUAL "that should have worked!!" moments to deal with.
-# I really don't want false ones mixed in. You want to reward your brain for finding good solutions, after all.
-parser.add_argument('--clear-screen', action='store_true', help='Clear the screen before starting; useful for development, to avoid seeing outdated errors')
-parser.add_argument('--restart-on-changes', action='store_true', help='Restart the app when the source code is changed, for development')
-parser.add_argument('--recode-samples', action='store_true', help='Open and save each file in samples/, for testing')
-
-parser.add_argument('filename', nargs='?', default=None, help='Path to a file to open. File will be created if it doesn\'t exist.')
-
-def update_cli_help_on_readme():
-    """Update the readme with the current CLI usage info"""
-    readme_help_start = re.compile(r"```\n.*--help\n")
-    readme_help_end = re.compile(r"```")
-    readme_file_path = os.path.join(os.path.dirname(__file__), "../../README.md")
-    with open(readme_file_path, "r+", encoding="utf-8") as f:
-        # By default, argparse uses the terminal width for formatting help text,
-        # even when using format_help() to get a string.
-        # The only way to override that is to override the formatter_class.
-        # This is hacky, but it seems like the simplest way to fix the width
-        # without creating a separate ArgumentParser, and without breaking the wrapping for --help.
-        # This lambda works because python uses the same syntax for construction and function calls,
-        # so formatter_class doesn't need to be an actual class.
-        # See: https://stackoverflow.com/questions/44333577/explain-lambda-argparse-helpformatterprog-width
-        width = 80
-        old_formatter_class = parser.formatter_class
-        parser.formatter_class = lambda prog: argparse.HelpFormatter(prog, width=width)
-        help_text = parser.format_help()
-        parser.formatter_class = old_formatter_class
-        
-        md = f.read()
-        start_match = readme_help_start.search(md)
-        if start_match is None:
-            raise Exception("Couldn't find help section in readme")
-        start = start_match.end()
-        end_match = readme_help_end.search(md, start)
-        if end_match is None:
-            raise Exception("Couldn't find end of help section in readme")
-        end = end_match.start()
-        md = md[:start] + help_text + md[end:]
-        f.seek(0)
-        f.write(md)
-        f.truncate()
-# Manually disabled for release.
-# TODO: disable for release builds, while keeping it automatic during development.
-# (I could make this another dev flag, but I like the idea of it being automatic.)
-# (Maybe a pre-commit hook would be ideal, if it's worth the complexity.)
-# update_cli_help_on_readme()
-
-args = parser.parse_args()
-
+# Most arguments are handled at the end of the file,
+# but it may be important to do this one early.
 load_language(args.language)
 
-# Most arguments are handled at the end of the file.
 
 class MetaGlyphFont:
     def __init__(self, file_path: str, width: int, height: int, covered_characters: str):
@@ -4244,7 +4182,7 @@ Columns: {len(palette) // 2}
             allow_maximize=True,
             allow_minimize=True,
         )
-        help_text = parser.format_help()
+        help_text = get_help_text()
         window.content.mount(Container(Static(help_text, markup=False),  classes="help_text_container"))
         window.content.mount(Button(_("OK"), classes="ok submit"))
         self.mount(window)
@@ -5299,9 +5237,6 @@ Columns: {len(palette) // 2}
 if args.ascii_only:
     args.ascii_only_icons = True
 
-    import textual_paint.windows
-    textual_paint.windows.ascii_only = True
-
     from .ascii_borders import force_ascii_borders
     force_ascii_borders()
 

src/textual_paint/windows.py

@@ -14,9 +14,7 @@ from textual.containers import Container, Horizontal, Vertical
 from textual.css.query import NoMatches
 
 from .localization.i18n import get as _
-
-ascii_only = False
-"""This is overwritten in paint.py when --ascii-only is passed."""
+from .args import args
 
 class WindowTitleBar(Container):
     """A title bar widget."""
@@ -597,7 +595,7 @@ warning_icon_markup_ascii_dark_mode = """[#ffff00]
 [/]"""
 
 def get_warning_icon() -> Static:
-    markup = warning_icon_markup_ascii if ascii_only else warning_icon_markup_unicode
+    markup = warning_icon_markup_ascii if args.ascii_only else warning_icon_markup_unicode
     # TODO: Use warning_icon_markup_ascii_dark_mode for a less blocky looking outline in dark mode.
     return Static(markup, classes="warning_icon message_box_icon")
 
@@ -664,7 +662,7 @@ question_icon_console_markup_ascii = """
 question_icon_console_markup_ascii = question_icon_console_markup_ascii.replace(" on rgb(128,128,128)", "")
 
 def get_question_icon() -> Static:
-    markup = question_icon_console_markup_ascii if ascii_only else question_icon_console_markup
+    markup = question_icon_console_markup_ascii if args.ascii_only else question_icon_console_markup
     return Static(markup, classes="question_icon message_box_icon")
 
 
@@ -691,7 +689,7 @@ paint_icon_console_markup_ascii = """
 paint_icon_console_markup_ascii = paint_icon_console_markup_ascii.replace(" on rgb(255,0,255)", "")
 
 def get_paint_icon() -> Static:
-    markup = paint_icon_console_markup_ascii if ascii_only else paint_icon_console_markup
+    markup = paint_icon_console_markup_ascii if args.ascii_only else paint_icon_console_markup
     return Static(markup, classes="paint_icon message_box_icon")