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- # -*- coding: utf-8 -*-
- """
- click.parser
- ~~~~~~~~~~~~
-
- This module started out as largely a copy paste from the stdlib's
- optparse module with the features removed that we do not need from
- optparse because we implement them in Click on a higher level (for
- instance type handling, help formatting and a lot more).
-
- The plan is to remove more and more from here over time.
-
- The reason this is a different module and not optparse from the stdlib
- is that there are differences in 2.x and 3.x about the error messages
- generated and optparse in the stdlib uses gettext for no good reason
- and might cause us issues.
- """
-
- import re
- from collections import deque
- from .exceptions import UsageError, NoSuchOption, BadOptionUsage, \
- BadArgumentUsage
-
-
- def _unpack_args(args, nargs_spec):
- """Given an iterable of arguments and an iterable of nargs specifications,
- it returns a tuple with all the unpacked arguments at the first index
- and all remaining arguments as the second.
-
- The nargs specification is the number of arguments that should be consumed
- or `-1` to indicate that this position should eat up all the remainders.
-
- Missing items are filled with `None`.
- """
- args = deque(args)
- nargs_spec = deque(nargs_spec)
- rv = []
- spos = None
-
- def _fetch(c):
- try:
- if spos is None:
- return c.popleft()
- else:
- return c.pop()
- except IndexError:
- return None
-
- while nargs_spec:
- nargs = _fetch(nargs_spec)
- if nargs == 1:
- rv.append(_fetch(args))
- elif nargs > 1:
- x = [_fetch(args) for _ in range(nargs)]
- # If we're reversed, we're pulling in the arguments in reverse,
- # so we need to turn them around.
- if spos is not None:
- x.reverse()
- rv.append(tuple(x))
- elif nargs < 0:
- if spos is not None:
- raise TypeError('Cannot have two nargs < 0')
- spos = len(rv)
- rv.append(None)
-
- # spos is the position of the wildcard (star). If it's not `None`,
- # we fill it with the remainder.
- if spos is not None:
- rv[spos] = tuple(args)
- args = []
- rv[spos + 1:] = reversed(rv[spos + 1:])
-
- return tuple(rv), list(args)
-
-
- def _error_opt_args(nargs, opt):
- if nargs == 1:
- raise BadOptionUsage(opt, '%s option requires an argument' % opt)
- raise BadOptionUsage(opt, '%s option requires %d arguments' % (opt, nargs))
-
-
- def split_opt(opt):
- first = opt[:1]
- if first.isalnum():
- return '', opt
- if opt[1:2] == first:
- return opt[:2], opt[2:]
- return first, opt[1:]
-
-
- def normalize_opt(opt, ctx):
- if ctx is None or ctx.token_normalize_func is None:
- return opt
- prefix, opt = split_opt(opt)
- return prefix + ctx.token_normalize_func(opt)
-
-
- def split_arg_string(string):
- """Given an argument string this attempts to split it into small parts."""
- rv = []
- for match in re.finditer(r"('([^'\\]*(?:\\.[^'\\]*)*)'"
- r'|"([^"\\]*(?:\\.[^"\\]*)*)"'
- r'|\S+)\s*', string, re.S):
- arg = match.group().strip()
- if arg[:1] == arg[-1:] and arg[:1] in '"\'':
- arg = arg[1:-1].encode('ascii', 'backslashreplace') \
- .decode('unicode-escape')
- try:
- arg = type(string)(arg)
- except UnicodeError:
- pass
- rv.append(arg)
- return rv
-
-
- class Option(object):
-
- def __init__(self, opts, dest, action=None, nargs=1, const=None, obj=None):
- self._short_opts = []
- self._long_opts = []
- self.prefixes = set()
-
- for opt in opts:
- prefix, value = split_opt(opt)
- if not prefix:
- raise ValueError('Invalid start character for option (%s)'
- % opt)
- self.prefixes.add(prefix[0])
- if len(prefix) == 1 and len(value) == 1:
- self._short_opts.append(opt)
- else:
- self._long_opts.append(opt)
- self.prefixes.add(prefix)
-
- if action is None:
- action = 'store'
-
- self.dest = dest
- self.action = action
- self.nargs = nargs
- self.const = const
- self.obj = obj
-
- @property
- def takes_value(self):
- return self.action in ('store', 'append')
-
- def process(self, value, state):
- if self.action == 'store':
- state.opts[self.dest] = value
- elif self.action == 'store_const':
- state.opts[self.dest] = self.const
- elif self.action == 'append':
- state.opts.setdefault(self.dest, []).append(value)
- elif self.action == 'append_const':
- state.opts.setdefault(self.dest, []).append(self.const)
- elif self.action == 'count':
- state.opts[self.dest] = state.opts.get(self.dest, 0) + 1
- else:
- raise ValueError('unknown action %r' % self.action)
- state.order.append(self.obj)
-
-
- class Argument(object):
-
- def __init__(self, dest, nargs=1, obj=None):
- self.dest = dest
- self.nargs = nargs
- self.obj = obj
-
- def process(self, value, state):
- if self.nargs > 1:
- holes = sum(1 for x in value if x is None)
- if holes == len(value):
- value = None
- elif holes != 0:
- raise BadArgumentUsage('argument %s takes %d values'
- % (self.dest, self.nargs))
- state.opts[self.dest] = value
- state.order.append(self.obj)
-
-
- class ParsingState(object):
-
- def __init__(self, rargs):
- self.opts = {}
- self.largs = []
- self.rargs = rargs
- self.order = []
-
-
- class OptionParser(object):
- """The option parser is an internal class that is ultimately used to
- parse options and arguments. It's modelled after optparse and brings
- a similar but vastly simplified API. It should generally not be used
- directly as the high level Click classes wrap it for you.
-
- It's not nearly as extensible as optparse or argparse as it does not
- implement features that are implemented on a higher level (such as
- types or defaults).
-
- :param ctx: optionally the :class:`~click.Context` where this parser
- should go with.
- """
-
- def __init__(self, ctx=None):
- #: The :class:`~click.Context` for this parser. This might be
- #: `None` for some advanced use cases.
- self.ctx = ctx
- #: This controls how the parser deals with interspersed arguments.
- #: If this is set to `False`, the parser will stop on the first
- #: non-option. Click uses this to implement nested subcommands
- #: safely.
- self.allow_interspersed_args = True
- #: This tells the parser how to deal with unknown options. By
- #: default it will error out (which is sensible), but there is a
- #: second mode where it will ignore it and continue processing
- #: after shifting all the unknown options into the resulting args.
- self.ignore_unknown_options = False
- if ctx is not None:
- self.allow_interspersed_args = ctx.allow_interspersed_args
- self.ignore_unknown_options = ctx.ignore_unknown_options
- self._short_opt = {}
- self._long_opt = {}
- self._opt_prefixes = set(['-', '--'])
- self._args = []
-
- def add_option(self, opts, dest, action=None, nargs=1, const=None,
- obj=None):
- """Adds a new option named `dest` to the parser. The destination
- is not inferred (unlike with optparse) and needs to be explicitly
- provided. Action can be any of ``store``, ``store_const``,
- ``append``, ``appnd_const`` or ``count``.
-
- The `obj` can be used to identify the option in the order list
- that is returned from the parser.
- """
- if obj is None:
- obj = dest
- opts = [normalize_opt(opt, self.ctx) for opt in opts]
- option = Option(opts, dest, action=action, nargs=nargs,
- const=const, obj=obj)
- self._opt_prefixes.update(option.prefixes)
- for opt in option._short_opts:
- self._short_opt[opt] = option
- for opt in option._long_opts:
- self._long_opt[opt] = option
-
- def add_argument(self, dest, nargs=1, obj=None):
- """Adds a positional argument named `dest` to the parser.
-
- The `obj` can be used to identify the option in the order list
- that is returned from the parser.
- """
- if obj is None:
- obj = dest
- self._args.append(Argument(dest=dest, nargs=nargs, obj=obj))
-
- def parse_args(self, args):
- """Parses positional arguments and returns ``(values, args, order)``
- for the parsed options and arguments as well as the leftover
- arguments if there are any. The order is a list of objects as they
- appear on the command line. If arguments appear multiple times they
- will be memorized multiple times as well.
- """
- state = ParsingState(args)
- try:
- self._process_args_for_options(state)
- self._process_args_for_args(state)
- except UsageError:
- if self.ctx is None or not self.ctx.resilient_parsing:
- raise
- return state.opts, state.largs, state.order
-
- def _process_args_for_args(self, state):
- pargs, args = _unpack_args(state.largs + state.rargs,
- [x.nargs for x in self._args])
-
- for idx, arg in enumerate(self._args):
- arg.process(pargs[idx], state)
-
- state.largs = args
- state.rargs = []
-
- def _process_args_for_options(self, state):
- while state.rargs:
- arg = state.rargs.pop(0)
- arglen = len(arg)
- # Double dashes always handled explicitly regardless of what
- # prefixes are valid.
- if arg == '--':
- return
- elif arg[:1] in self._opt_prefixes and arglen > 1:
- self._process_opts(arg, state)
- elif self.allow_interspersed_args:
- state.largs.append(arg)
- else:
- state.rargs.insert(0, arg)
- return
-
- # Say this is the original argument list:
- # [arg0, arg1, ..., arg(i-1), arg(i), arg(i+1), ..., arg(N-1)]
- # ^
- # (we are about to process arg(i)).
- #
- # Then rargs is [arg(i), ..., arg(N-1)] and largs is a *subset* of
- # [arg0, ..., arg(i-1)] (any options and their arguments will have
- # been removed from largs).
- #
- # The while loop will usually consume 1 or more arguments per pass.
- # If it consumes 1 (eg. arg is an option that takes no arguments),
- # then after _process_arg() is done the situation is:
- #
- # largs = subset of [arg0, ..., arg(i)]
- # rargs = [arg(i+1), ..., arg(N-1)]
- #
- # If allow_interspersed_args is false, largs will always be
- # *empty* -- still a subset of [arg0, ..., arg(i-1)], but
- # not a very interesting subset!
-
- def _match_long_opt(self, opt, explicit_value, state):
- if opt not in self._long_opt:
- possibilities = [word for word in self._long_opt
- if word.startswith(opt)]
- raise NoSuchOption(opt, possibilities=possibilities, ctx=self.ctx)
-
- option = self._long_opt[opt]
- if option.takes_value:
- # At this point it's safe to modify rargs by injecting the
- # explicit value, because no exception is raised in this
- # branch. This means that the inserted value will be fully
- # consumed.
- if explicit_value is not None:
- state.rargs.insert(0, explicit_value)
-
- nargs = option.nargs
- if len(state.rargs) < nargs:
- _error_opt_args(nargs, opt)
- elif nargs == 1:
- value = state.rargs.pop(0)
- else:
- value = tuple(state.rargs[:nargs])
- del state.rargs[:nargs]
-
- elif explicit_value is not None:
- raise BadOptionUsage(opt, '%s option does not take a value' % opt)
-
- else:
- value = None
-
- option.process(value, state)
-
- def _match_short_opt(self, arg, state):
- stop = False
- i = 1
- prefix = arg[0]
- unknown_options = []
-
- for ch in arg[1:]:
- opt = normalize_opt(prefix + ch, self.ctx)
- option = self._short_opt.get(opt)
- i += 1
-
- if not option:
- if self.ignore_unknown_options:
- unknown_options.append(ch)
- continue
- raise NoSuchOption(opt, ctx=self.ctx)
- if option.takes_value:
- # Any characters left in arg? Pretend they're the
- # next arg, and stop consuming characters of arg.
- if i < len(arg):
- state.rargs.insert(0, arg[i:])
- stop = True
-
- nargs = option.nargs
- if len(state.rargs) < nargs:
- _error_opt_args(nargs, opt)
- elif nargs == 1:
- value = state.rargs.pop(0)
- else:
- value = tuple(state.rargs[:nargs])
- del state.rargs[:nargs]
-
- else:
- value = None
-
- option.process(value, state)
-
- if stop:
- break
-
- # If we got any unknown options we re-combinate the string of the
- # remaining options and re-attach the prefix, then report that
- # to the state as new larg. This way there is basic combinatorics
- # that can be achieved while still ignoring unknown arguments.
- if self.ignore_unknown_options and unknown_options:
- state.largs.append(prefix + ''.join(unknown_options))
-
- def _process_opts(self, arg, state):
- explicit_value = None
- # Long option handling happens in two parts. The first part is
- # supporting explicitly attached values. In any case, we will try
- # to long match the option first.
- if '=' in arg:
- long_opt, explicit_value = arg.split('=', 1)
- else:
- long_opt = arg
- norm_long_opt = normalize_opt(long_opt, self.ctx)
-
- # At this point we will match the (assumed) long option through
- # the long option matching code. Note that this allows options
- # like "-foo" to be matched as long options.
- try:
- self._match_long_opt(norm_long_opt, explicit_value, state)
- except NoSuchOption:
- # At this point the long option matching failed, and we need
- # to try with short options. However there is a special rule
- # which says, that if we have a two character options prefix
- # (applies to "--foo" for instance), we do not dispatch to the
- # short option code and will instead raise the no option
- # error.
- if arg[:2] not in self._opt_prefixes:
- return self._match_short_opt(arg, state)
- if not self.ignore_unknown_options:
- raise
- state.largs.append(arg)
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