help_doc_gen.py

#!/usr/bin/env python3

import collections
import re
import sys

# Config help binding extraction regex
CONF_HELP_BINDING_RE = r'bind -T HELP (\w) (.*)(?:\s+#\s+(.*))'

# Output formatters
HELP_PAGE_LINE_FMT = '{key:<8}{doc}'
HELP_PAGE_HEADER = 'You have typed C-h, the help character. Type a Help option:\n(Type q to exit the Help command.)'
HelpBinding = collections.namedtuple('HelpBinding', 'key command docstring')

def extract_conf_file_help_bindings(conf_file):
    """Extract all lines in our config that are help key bindings and return them as aa list of
    HelpBinding namedtuples."""
    with open(conf_file) as lines:
        return [HelpBinding(*re.match(CONF_HELP_BINDING_RE, line).groups()) for line in lines
                if re.match(CONF_HELP_BINDING_RE, line)]

def sort_help_bindings_by_key(help_bindings):
    """Sort a list of help bindings alphabetically by key."""
    return sorted(help_bindings, key=lambda x: x.key.lower())


def format_help_binding(help_binding):
    """Format a HelpBinding namedtuple for output to the hmux help page."""
    return HELP_PAGE_LINE_FMT.format(
        key=help_binding.key,
        doc=(help_binding.docstring)
    )

def main():
    """Main"""
    conf_file = sys.argv[1]
    help_bindings = extract_conf_file_help_bindings(conf_file)
    help_bindings = sort_help_bindings_by_key(help_bindings)

    print(HELP_PAGE_HEADER + '\n')
    for help_binding in help_bindings:
        print(format_help_binding(help_binding))


if __name__ == '__main__':
    main()