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Editing: docopt.py
"""Pythonic command-line interface parser that will make you smile. * http://docopt.org * Repository and issue-tracker: https://github.com/docopt/docopt * Licensed under terms of MIT license (see LICENSE-MIT) * Copyright (c) 2013 Vladimir Keleshev, vladimir@keleshev.com """ import sys import re __all__ = ['docopt'] __version__ = '0.6.2' class DocoptLanguageError(Exception): """Error in construction of usage-message by developer.""" class DocoptExit(SystemExit): """Exit in case user invoked program with incorrect arguments.""" usage = '' def __init__(self, message=''): SystemExit.__init__(self, (message + '\n' + self.usage).strip()) class Pattern(object): def __eq__(self, other): return repr(self) == repr(other) def __hash__(self): return hash(repr(self)) def fix(self): self.fix_identities() self.fix_repeating_arguments() return self def fix_identities(self, uniq=None): """Make pattern-tree tips point to same object if they are equal.""" if not hasattr(self, 'children'): return self uniq = list(set(self.flat())) if uniq is None else uniq for i, c in enumerate(self.children): if not hasattr(c, 'children'): assert c in uniq self.children[i] = uniq[uniq.index(c)] else: c.fix_identities(uniq) def fix_repeating_arguments(self): """Fix elements that should accumulate/increment values.""" either = [list(c.children) for c in self.either.children] for case in either: for e in [c for c in case if case.count(c) > 1]: if type(e) is Argument or type(e) is Option and e.argcount: if e.value is None: e.value = [] elif type(e.value) is not list: e.value = e.value.split() if type(e) is Command or type(e) is Option and e.argcount == 0: e.value = 0 return self @property def either(self): """Transform pattern into an equivalent, with only top-level Either.""" # Currently the pattern will not be equivalent, but more "narrow", # although good enough to reason about list arguments. ret = [] groups = [[self]] while groups: children = groups.pop(0) types = [type(c) for c in children] if Either in types: either = [c for c in children if type(c) is Either][0] children.pop(children.index(either)) for c in either.children: groups.append([c] + children) elif Required in types: required = [c for c in children if type(c) is Required][0] children.pop(children.index(required)) groups.append(list(required.children) + children) elif Optional in types: optional = [c for c in children if type(c) is Optional][0] children.pop(children.index(optional)) groups.append(list(optional.children) + children) elif AnyOptions in types: optional = [c for c in children if type(c) is AnyOptions][0] children.pop(children.index(optional)) groups.append(list(optional.children) + children) elif OneOrMore in types: oneormore = [c for c in children if type(c) is OneOrMore][0] children.pop(children.index(oneormore)) groups.append(list(oneormore.children) * 2 + children) else: ret.append(children) return Either(*[Required(*e) for e in ret]) class ChildPattern(Pattern): def __init__(self, name, value=None): self.name = name self.value = value def __repr__(self): return '%s(%r, %r)' % (self.__class__.__name__, self.name, self.value) def flat(self, *types): return [self] if not types or type(self) in types else [] def match(self, left, collected=None): collected = [] if collected is None else collected pos, match = self.single_match(left) if match is None: return False, left, collected left_ = left[:pos] + left[pos + 1:] same_name = [a for a in collected if a.name == self.name] if type(self.value) in (int, list): if type(self.value) is int: increment = 1 else: increment = ([match.value] if type(match.value) is str else match.value) if not same_name: match.value = increment return True, left_, collected + [match] same_name[0].value += increment return True, left_, collected return True, left_, collected + [match] class ParentPattern(Pattern): def __init__(self, *children): self.children = list(children) def __repr__(self): return '%s(%s)' % (self.__class__.__name__, ', '.join(repr(a) for a in self.children)) def flat(self, *types): if type(self) in types: return [self] return sum([c.flat(*types) for c in self.children], []) class Argument(ChildPattern): def single_match(self, left): for n, p in enumerate(left): if type(p) is Argument: return n, Argument(self.name, p.value) return None, None @classmethod def parse(class_, source): name = re.findall('(<\S*?>)', source)[0] value = re.findall('\[default: (.*)\]', source, flags=re.I) return class_(name, value[0] if value else None) class Command(Argument): def __init__(self, name, value=False): self.name = name self.value = value def single_match(self, left): for n, p in enumerate(left): if type(p) is Argument: if p.value == self.name: return n, Command(self.name, True) else: break return None, None class Option(ChildPattern): def __init__(self, short=None, long=None, argcount=0, value=False): assert argcount in (0, 1) self.short, self.long = short, long self.argcount, self.value = argcount, value self.value = None if value is False and argcount else value @classmethod def parse(class_, option_description): short, long, argcount, value = None, None, 0, False options, _, description = option_description.strip().partition(' ') options = options.replace(',', ' ').replace('=', ' ') for s in options.split(): if s.startswith('--'): long = s elif s.startswith('-'): short = s else: argcount = 1 if argcount: matched = re.findall('\[default: (.*)\]', description, flags=re.I) value = matched[0] if matched else None return class_(short, long, argcount, value) def single_match(self, left): for n, p in enumerate(left): if self.name == p.name: return n, p return None, None @property def name(self): return self.long or self.short def __repr__(self): return 'Option(%r, %r, %r, %r)' % (self.short, self.long, self.argcount, self.value) class Required(ParentPattern): def match(self, left, collected=None): collected = [] if collected is None else collected l = left c = collected for p in self.children: matched, l, c = p.match(l, c) if not matched: return False, left, collected return True, l, c class Optional(ParentPattern): def match(self, left, collected=None): collected = [] if collected is None else collected for p in self.children: m, left, collected = p.match(left, collected) return True, left, collected class AnyOptions(Optional): """Marker/placeholder for [options] shortcut.""" class OneOrMore(ParentPattern): def match(self, left, collected=None): assert len(self.children) == 1 collected = [] if collected is None else collected l = left c = collected l_ = None matched = True times = 0 while matched: # could it be that something didn't match but changed l or c? matched, l, c = self.children[0].match(l, c) times += 1 if matched else 0 if l_ == l: break l_ = l if times >= 1: return True, l, c return False, left, collected class Either(ParentPattern): def match(self, left, collected=None): collected = [] if collected is None else collected outcomes = [] for p in self.children: matched, _, _ = outcome = p.match(left, collected) if matched: outcomes.append(outcome) if outcomes: return min(outcomes, key=lambda outcome: len(outcome[1])) return False, left, collected class TokenStream(list): def __init__(self, source, error): self += source.split() if hasattr(source, 'split') else source self.error = error def move(self): return self.pop(0) if len(self) else None def current(self): return self[0] if len(self) else None def parse_long(tokens, options): """long ::= '--' chars [ ( ' ' | '=' ) chars ] ;""" long, eq, value = tokens.move().partition('=') assert long.startswith('--') value = None if eq == value == '' else value similar = [o for o in options if o.long == long] if tokens.error is DocoptExit and similar == []: # if no exact match similar = [o for o in options if o.long and o.long.startswith(long)] if len(similar) > 1: # might be simply specified ambiguously 2+ times? raise tokens.error('%s is not a unique prefix: %s?' % (long, ', '.join(o.long for o in similar))) elif len(similar) < 1: argcount = 1 if eq == '=' else 0 o = Option(None, long, argcount) options.append(o) if tokens.error is DocoptExit: o = Option(None, long, argcount, value if argcount else True) else: o = Option(similar[0].short, similar[0].long, similar[0].argcount, similar[0].value) if o.argcount == 0: if value is not None: raise tokens.error('%s must not have an argument' % o.long) else: if value is None: if tokens.current() is None: raise tokens.error('%s requires argument' % o.long) value = tokens.move() if tokens.error is DocoptExit: o.value = value if value is not None else True return [o] def parse_shorts(tokens, options): """shorts ::= '-' ( chars )* [ [ ' ' ] chars ] ;""" token = tokens.move() assert token.startswith('-') and not token.startswith('--') left = token.lstrip('-') parsed = [] while left != '': short, left = '-' + left[0], left[1:] similar = [o for o in options if o.short == short] if len(similar) > 1: raise tokens.error('%s is specified ambiguously %d times' % (short, len(similar))) elif len(similar) < 1: o = Option(short, None, 0) options.append(o) if tokens.error is DocoptExit: o = Option(short, None, 0, True) else: # why copying is necessary here? o = Option(short, similar[0].long, similar[0].argcount, similar[0].value) value = None if o.argcount != 0: if left == '': if tokens.current() is None: raise tokens.error('%s requires argument' % short) value = tokens.move() else: value = left left = '' if tokens.error is DocoptExit: o.value = value if value is not None else True parsed.append(o) return parsed def parse_pattern(source, options): tokens = TokenStream(re.sub(r'([\[\]\(\)\|]|\.\.\.)', r' \1 ', source), DocoptLanguageError) result = parse_expr(tokens, options) if tokens.current() is not None: raise tokens.error('unexpected ending: %r' % ' '.join(tokens)) return Required(*result) def parse_expr(tokens, options): """expr ::= seq ( '|' seq )* ;""" seq = parse_seq(tokens, options) if tokens.current() != '|': return seq result = [Required(*seq)] if len(seq) > 1 else seq while tokens.current() == '|': tokens.move() seq = parse_seq(tokens, options) result += [Required(*seq)] if len(seq) > 1 else seq return [Either(*result)] if len(result) > 1 else result def parse_seq(tokens, options): """seq ::= ( atom [ '...' ] )* ;""" result = [] while tokens.current() not in [None, ']', ')', '|']: atom = parse_atom(tokens, options) if tokens.current() == '...': atom = [OneOrMore(*atom)] tokens.move() result += atom return result def parse_atom(tokens, options): """atom ::= '(' expr ')' | '[' expr ']' | 'options' | long | shorts | argument | command ; """ token = tokens.current() result = [] if token in '([': tokens.move() matching, pattern = {'(': [')', Required], '[': [']', Optional]}[token] result = pattern(*parse_expr(tokens, options)) if tokens.move() != matching: raise tokens.error("unmatched '%s'" % token) return [result] elif token == 'options': tokens.move() return [AnyOptions()] elif token.startswith('--') and token != '--': return parse_long(tokens, options) elif token.startswith('-') and token not in ('-', '--'): return parse_shorts(tokens, options) elif token.startswith('<') and token.endswith('>') or token.isupper(): return [Argument(tokens.move())] else: return [Command(tokens.move())] def parse_argv(tokens, options, options_first=False): """Parse command-line argument vector. If options_first: argv ::= [ long | shorts ]* [ argument ]* [ '--' [ argument ]* ] ; else: argv ::= [ long | shorts | argument ]* [ '--' [ argument ]* ] ; """ parsed = [] while tokens.current() is not None: if tokens.current() == '--': return parsed + [Argument(None, v) for v in tokens] elif tokens.current().startswith('--'): parsed += parse_long(tokens, options) elif tokens.current().startswith('-') and tokens.current() != '-': parsed += parse_shorts(tokens, options) elif options_first: return parsed + [Argument(None, v) for v in tokens] else: parsed.append(Argument(None, tokens.move())) return parsed def parse_defaults(doc): # in python < 2.7 you can't pass flags=re.MULTILINE split = re.split('\n *(<\S+?>|-\S+?)', doc)[1:] split = [s1 + s2 for s1, s2 in zip(split[::2], split[1::2])] options = [Option.parse(s) for s in split if s.startswith('-')] #arguments = [Argument.parse(s) for s in split if s.startswith('<')] #return options, arguments return options def printable_usage(doc): # in python < 2.7 you can't pass flags=re.IGNORECASE usage_split = re.split(r'([Uu][Ss][Aa][Gg][Ee]:)', doc) if len(usage_split) < 3: raise DocoptLanguageError('"usage:" (case-insensitive) not found.') if len(usage_split) > 3: raise DocoptLanguageError('More than one "usage:" (case-insensitive).') return re.split(r'\n\s*\n', ''.join(usage_split[1:]))[0].strip() def formal_usage(printable_usage): pu = printable_usage.split()[1:] # split and drop "usage:" return '( ' + ' '.join(') | (' if s == pu[0] else s for s in pu[1:]) + ' )' def extras(help, version, options, doc): if help and any((o.name in ('-h', '--help')) and o.value for o in options): print(doc.strip("\n")) sys.exit() if version and any(o.name == '--version' and o.value for o in options): print(version) sys.exit() class Dict(dict): def __repr__(self): return '{%s}' % ',\n '.join('%r: %r' % i for i in sorted(self.items())) def docopt(doc, argv=None, help=True, version=None, options_first=False): """Parse `argv` based on command-line interface described in `doc`. `docopt` creates your command-line interface based on its description that you pass as `doc`. Such description can contain --options, <positional-argument>, commands, which could be [optional], (required), (mutually | exclusive) or repeated... Parameters ---------- doc : str Description of your command-line interface. argv : list of str, optional Argument vector to be parsed. sys.argv[1:] is used if not provided. help : bool (default: True) Set to False to disable automatic help on -h or --help options. version : any object If passed, the object will be printed if --version is in `argv`. options_first : bool (default: False) Set to True to require options preceed positional arguments, i.e. to forbid options and positional arguments intermix. Returns ------- args : dict A dictionary, where keys are names of command-line elements such as e.g. "--verbose" and "<path>", and values are the parsed values of those elements. Example ------- >>> from docopt import docopt >>> doc = ''' Usage: my_program tcp <host> <port> [--timeout=<seconds>] my_program serial <port> [--baud=<n>] [--timeout=<seconds>] my_program (-h | --help | --version) Options: -h, --help Show this screen and exit. --baud=<n> Baudrate [default: 9600] ''' >>> argv = ['tcp', '127.0.0.1', '80', '--timeout', '30'] >>> docopt(doc, argv) {'--baud': '9600', '--help': False, '--timeout': '30', '--version': False, '<host>': '127.0.0.1', '<port>': '80', 'serial': False, 'tcp': True} See also -------- * For video introduction see http://docopt.org * Full documentation is available in README.rst as well as online at https://github.com/docopt/docopt#readme """ if argv is None: argv = sys.argv[1:] DocoptExit.usage = printable_usage(doc) options = parse_defaults(doc) pattern = parse_pattern(formal_usage(DocoptExit.usage), options) # [default] syntax for argument is disabled #for a in pattern.flat(Argument): # same_name = [d for d in arguments if d.name == a.name] # if same_name: # a.value = same_name[0].value argv = parse_argv(TokenStream(argv, DocoptExit), list(options), options_first) pattern_options = set(pattern.flat(Option)) for ao in pattern.flat(AnyOptions): doc_options = parse_defaults(doc) ao.children = list(set(doc_options) - pattern_options) #if any_options: # ao.children += [Option(o.short, o.long, o.argcount) # for o in argv if type(o) is Option] extras(help, version, argv, doc) matched, left, collected = pattern.fix().match(argv) if matched and left == []: # better error message if left? return Dict((a.name, a.value) for a in (pattern.flat() + collected)) raise DocoptExit()
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