git-linter/git_lint/git_lint_options.py

import os
import sys
import getopt
import gettext

_ = gettext.gettext


def make_rational_options(optlist, args):

    # OptionTupleList -> (getOptOptions -> dictionaryOfOptions)
    def make_options_rationalizer(optlist):
        """Takes a list of option tuples, and returns a function that takes
            the output of getopt and reduces it to the longopt key and
            associated values as a dictionary.
        """
    
        def make_opt_assoc(prefix, pos):
            def associater(acc, it):
                acc[(prefix + it[pos])] = it[1]
                return acc
            return associater
    
        short_opt_assoc = make_opt_assoc('-', 0)
        long_opt_assoc = make_opt_assoc('--', 1)
    
        def make_full_set(acc, i):
            return long_opt_assoc(short_opt_assoc(acc, i), i)
    
        fullset = reduce(make_full_set, optlist, {})
    
        def rationalizer(acc, it):
            acc[fullset[it[0]]] = it[1]
            return acc
    
        return rationalizer

    
    # (OptionTupleList, dictionaryOfOptions) -> (dictionaryOfOptions, excludedOptions)
    def remove_conflicted_options(optlist, request):
        """Takes our list of option tuples, and a cleaned copy of what was
            requested from getopt, and returns a copy of the request
            without any options that are marked as superseded, along with
            the list of superseded options
        """
        def get_excluded_keys(memo, opt):
            return memo + (len(opt) > 4 and opt[4] or [])
    
        keys = request.keys()
        marked = [option for option in optlist if option[1] in keys]
        exclude = reduce(get_excluded_keys, marked, [])
        excluded = [key for key in keys if key in exclude]
        cleaned = {key: request[key] for key in keys
                   if key not in excluded}
        return (cleaned, excluded)
    
    def shortoptstogo(i):
        return i[0] + (i[2] and ':' or '')

    def longoptstogo(i):
        return i[1] + (i[2] and '=' or '')

    optstringsshort = ''.join([shortoptstogo(opt) for opt in optlist])
    optstringslong = [longoptstogo(opt) for opt in optlist]
    (options, filenames) = getopt.getopt(args[1:], optstringsshort,
                                         optstringslong)

    # Turns what getopt returns into something more human-readable
    rationalize_options = make_options_rationalizer(optlist)

    # Remove any options that
    (retoptions, excluded) = remove_conflicted_options(
        optlist, reduce(rationalize_options, options, {}))

    return (retoptions, filenames, excluded)