cpython/Lib/distutils/fancy_getopt.py

153 lines
5.1 KiB
Python

"""distutils.fancy_getopt
Wrapper around the standard getopt module that provides the following
additional features:
* short and long options are tied together
* options have help strings, so fancy_getopt could potentially
create a complete usage summary
* options set attributes of a passed-in object
"""
# created 1999/03/03, Greg Ward
__rcsid__ = "$Id$"
import string, re
from types import *
import getopt
from distutils.errors import *
# Much like command_re in distutils.core, this is close to but not quite
# the same as a Python NAME -- except, in the spirit of most GNU
# utilities, we use '-' in place of '_'. (The spirit of LISP lives on!)
# The similarities to NAME are again not a coincidence...
longopt_pat = r'[a-zA-Z](?:[a-zA-Z0-9-]*)'
longopt_re = re.compile (r'^%s$' % longopt_pat)
# For recognizing "negative alias" options, eg. "quiet=!verbose"
neg_alias_re = re.compile ("^(%s)=!(%s)$" % (longopt_pat, longopt_pat))
# This is used to translate long options to legitimate Python identifiers
# (for use as attributes of some object).
longopt_xlate = string.maketrans ('-', '_')
def fancy_getopt (options, object, args):
# The 'options' table is a list of 3-tuples:
# (long_option, short_option, help_string)
# if an option takes an argument, its long_option should have '='
# appended; short_option should just be a single character, no ':' in
# any case. If a long_option doesn't have a corresponding
# short_option, short_option should be None. All option tuples must
# have long options.
# Build the short_opts string and long_opts list, remembering how
# the two are tied together
short_opts = [] # we'll join 'em when done
long_opts = []
short2long = {}
attr_name = {}
takes_arg = {}
neg_alias = {}
for option in options:
try:
(long, short, help) = option
except ValueError:
raise DistutilsGetoptError, \
"invalid option tuple " + str (option)
# Type-check the option names
if type (long) is not StringType or len (long) < 2:
raise DistutilsGetoptError, \
"long option '%s' must be a string of length >= 2" % \
long
if (not ((short is None) or
(type (short) is StringType and len (short) == 1))):
raise DistutilsGetoptError, \
"short option '%s' must be None or string of length 1" % \
short
long_opts.append (long)
if long[-1] == '=': # option takes an argument?
if short: short = short + ':'
long = long[0:-1]
takes_arg[long] = 1
else:
# Is option is a "negative alias" for some other option (eg.
# "quiet=!verbose")?
match = neg_alias_re.match (long)
if match:
(alias_from, alias_to) = match.group (1,2)
if not takes_arg.has_key(alias_to) or takes_arg[alias_to]:
raise DistutilsGetoptError, \
("option '%s' is a negative alias for '%s', " +
"which either hasn't been defined yet " +
"or takes an argument") % (alias_from, alias_to)
long = alias_from
neg_alias[long] = alias_to
long_opts[-1] = long
takes_arg[long] = 0
else:
takes_arg[long] = 0
# Now enforce some bondage on the long option name, so we can later
# translate it to an attribute name in 'object'. Have to do this a
# bit late to make sure we've removed any trailing '='.
if not longopt_re.match (long):
raise DistutilsGetoptError, \
("invalid long option name '%s' " +
"(must be letters, numbers, hyphens only") % long
attr_name[long] = string.translate (long, longopt_xlate)
if short:
short_opts.append (short)
short2long[short[0]] = long
# end loop over 'options'
short_opts = string.join (short_opts)
try:
(opts, args) = getopt.getopt (args, short_opts, long_opts)
except getopt.error, msg:
raise DistutilsArgError, msg
for (opt, val) in opts:
if len (opt) == 2 and opt[0] == '-': # it's a short option
opt = short2long[opt[1]]
elif len (opt) > 2 and opt[0:2] == '--':
opt = opt[2:]
else:
raise RuntimeError, "getopt lies! (bad option string '%s')" % \
opt
attr = attr_name[opt]
if takes_arg[opt]:
setattr (object, attr, val)
else:
if val == '':
alias = neg_alias.get (opt)
if alias:
setattr (object, attr_name[alias], 0)
else:
setattr (object, attr, 1)
else:
raise RuntimeError, "getopt lies! (bad value '%s')" % value
# end loop over options found in 'args'
return args
# end fancy_getopt()