summaryrefslogtreecommitdiffstats
path: root/Lib/distutils/fancy_getopt.py
blob: 5de64e15da64cd3c434fea7d4c55caf01962a55a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
"""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

__revision__ = "$Id$"

import sys, 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('-', '_')

class FancyGetopt:
    """Wrapper around the standard 'getopt()' module that provides some
    handy extra functionality:
      * short and long options are tied together
      * options have help strings, and help text can be assembled
        from them
      * options set attributes of a passed-in object
      * boolean options can have "negative aliases" -- eg. if
        --quiet is the "negative alias" of --verbose, then "--quiet"
        on the command line sets 'verbose' to false
    """

    def __init__ (self, option_table=None):

        # The option table is (currently) 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.
        self.option_table = option_table

        # 'option_index' maps long option names to entries in the option
        # table (ie. those 3-tuples).
        self.option_index = {}
        if self.option_table:
            self._build_index()

        # 'alias' records (duh) alias options; {'foo': 'bar'} means
        # --foo is an alias for --bar
        self.alias = {}

        # 'negative_alias' keeps track of options that are the boolean
        # opposite of some other option
        self.negative_alias = {}

        # These keep track of the information in the option table.  We
        # don't actually populate these structures until we're ready to
        # parse the command-line, since the 'option_table' passed in here
        # isn't necessarily the final word.
        self.short_opts = []
        self.long_opts = []
        self.short2long = {}
        self.attr_name = {}
        self.takes_arg = {}

        # And 'option_order' is filled up in 'getopt()'; it records the
        # original order of options (and their values) on the command-line,
        # but expands short options, converts aliases, etc.
        self.option_order = []

    # __init__ ()


    def _build_index (self):
        self.option_index.clear()
        for option in self.option_table:
            self.option_index[option[0]] = option

    def set_option_table (self, option_table):
        self.option_table = option_table
        self._build_index()

    def add_option (self, long_option, short_option=None, help_string=None):
        if self.option_index.has_key(long_option):
            raise DistutilsGetoptError, \
                  "option conflict: already an option '%s'" % long_option
        else:
            option = (long_option, short_option, help_string)
            self.option_table.append(option)
            self.option_index[long_option] = option


    def has_option (self, long_option):
        """Return true if the option table for this parser has an
        option with long name 'long_option'."""
        return self.option_index.has_key(long_option)

    def get_attr_name (self, long_option):
        """Translate long option name 'long_option' to the form it
        has as an attribute of some object: ie., translate hyphens
        to underscores."""
        return string.translate(long_option, longopt_xlate)


    def _check_alias_dict (self, aliases, what):
        assert type(aliases) is DictionaryType
        for (alias, opt) in aliases.items():
            if not self.option_index.has_key(alias):
                raise DistutilsGetoptError, \
                      ("invalid %s '%s': "
                       "option '%s' not defined") % (what, alias, alias)
            if not self.option_index.has_key(opt):
                raise DistutilsGetoptError, \
                      ("invalid %s '%s': "
                       "aliased option '%s' not defined") % (what, alias, opt)

    def set_aliases (self, alias):
        """Set the aliases for this option parser."""
        self._check_alias_dict(alias, "alias")
        self.alias = alias

    def set_negative_aliases (self, negative_alias):
        """Set the negative aliases for this option parser.
        'negative_alias' should be a dictionary mapping option names to
        option names, both the key and value must already be defined
        in the option table."""
        self._check_alias_dict(negative_alias, "negative alias")
        self.negative_alias = negative_alias


    def _grok_option_table (self):
        """Populate the various data structures that keep tabs on the
        option table.  Called by 'getopt()' before it can do anything
        worthwhile.
        """
        self.long_opts = []
        self.short_opts = []
        self.short2long.clear()
        self.repeat = {}

        for option in self.option_table:
            if len(option) == 3:
                long, short, help = option
                repeat = 0
            elif len(option) == 4:
                long, short, help, repeat = option
            else:
                # the option table is part of the code, so simply
                # assert that it is correct
                assert "invalid option tuple: %s" % `option`

            # Type- and value-check the option names
            if type(long) is not StringType or len(long) < 2:
                raise DistutilsGetoptError, \
                      ("invalid 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, \
                      ("invalid short option '%s': "
                       "must a single character or None") % short

            self.repeat[long] = repeat
            self.long_opts.append(long)

            if long[-1] == '=':             # option takes an argument?
                if short: short = short + ':'
                long = long[0:-1]
                self.takes_arg[long] = 1
            else:

                # Is option is a "negative alias" for some other option (eg.
                # "quiet" == "!verbose")?
                alias_to = self.negative_alias.get(long)
                if alias_to is not None:
                    if self.takes_arg[alias_to]:
                        raise DistutilsGetoptError, \
                              ("invalid negative alias '%s': "
                               "aliased option '%s' takes a value") % \
                               (long, alias_to)

                    self.long_opts[-1] = long # XXX redundant?!
                    self.takes_arg[long] = 0

                else:
                    self.takes_arg[long] = 0

            # If this is an alias option, make sure its "takes arg" flag is
            # the same as the option it's aliased to.
            alias_to = self.alias.get(long)
            if alias_to is not None:
                if self.takes_arg[long] != self.takes_arg[alias_to]:
                    raise DistutilsGetoptError, \
                          ("invalid alias '%s': inconsistent with "
                           "aliased option '%s' (one of them takes a value, "
                           "the other doesn't") % (long, alias_to)


            # Now enforce some bondage on the long option name, so we can
            # later translate it to an attribute name on some 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

            self.attr_name[long] = self.get_attr_name(long)
            if short:
                self.short_opts.append(short)
                self.short2long[short[0]] = long

        # for option_table

    # _grok_option_table()


    def getopt (self, args=None, object=None):
        """Parse command-line options in args. Store as attributes on object.

        If 'args' is None or not supplied, uses 'sys.argv[1:]'.  If
        'object' is None or not supplied, creates a new OptionDummy
        object, stores option values there, and returns a tuple (args,
        object).  If 'object' is supplied, it is modified in place and
        'getopt()' just returns 'args'; in both cases, the returned
        'args' is a modified copy of the passed-in 'args' list, which
        is left untouched.
        """
        if args is None:
            args = sys.argv[1:]
        if object is None:
            object = OptionDummy()
            created_object = 1
        else:
            created_object = 0

        self._grok_option_table()

        short_opts = string.join(self.short_opts)
        try:
            opts, args = getopt.getopt(args, short_opts, self.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 = self.short2long[opt[1]]
            else:
                assert len(opt) > 2 and opt[:2] == '--'
                opt = opt[2:]

            alias = self.alias.get(opt)
            if alias:
                opt = alias

            if not self.takes_arg[opt]:     # boolean option?
                assert val == '', "boolean option can't have value"
                alias = self.negative_alias.get(opt)
                if alias:
                    opt = alias
                    val = 0
                else:
                    val = 1

            attr = self.attr_name[opt]
            # The only repeating option at the moment is 'verbose'.
            # It has a negative option -q quiet, which should set verbose = 0.
            if val and self.repeat.get(attr) is not None:
                val = getattr(object, attr, 0) + 1
            setattr(object, attr, val)
            self.option_order.append((opt, val))

        # for opts
        if created_object:
            return args, object
        else:
            return args

    # getopt()


    def get_option_order (self):
        """Returns the list of (option, value) tuples processed by the
        previous run of 'getopt()'.  Raises RuntimeError if
        'getopt()' hasn't been called yet.
        """
        if self.option_order is None:
            raise RuntimeError, "'getopt()' hasn't been called yet"
        else:
            return self.option_order


    def generate_help (self, header=None):
        """Generate help text (a list of strings, one per suggested line of
        output) from the option table for this FancyGetopt object.
        """
        # Blithely assume the option table is good: probably wouldn't call
        # 'generate_help()' unless you've already called 'getopt()'.

        # First pass: determine maximum length of long option names
        max_opt = 0
        for option in self.option_table:
            long = option[0]
            short = option[1]
            l = len(long)
            if long[-1] == '=':
                l = l - 1
            if short is not None:
                l = l + 5                   # " (-x)" where short == 'x'
            if l > max_opt:
                max_opt = l

        opt_width = max_opt + 2 + 2 + 2     # room for indent + dashes + gutter

        # Typical help block looks like this:
        #   --foo       controls foonabulation
        # Help block for longest option looks like this:
        #   --flimflam  set the flim-flam level
        # and with wrapped text:
        #   --flimflam  set the flim-flam level (must be between
        #               0 and 100, except on Tuesdays)
        # Options with short names will have the short name shown (but
        # it doesn't contribute to max_opt):
        #   --foo (-f)  controls foonabulation
        # If adding the short option would make the left column too wide,
        # we push the explanation off to the next line
        #   --flimflam (-l)
        #               set the flim-flam level
        # Important parameters:
        #   - 2 spaces before option block start lines
        #   - 2 dashes for each long option name
        #   - min. 2 spaces between option and explanation (gutter)
        #   - 5 characters (incl. space) for short option name

        # Now generate lines of help text.  (If 80 columns were good enough
        # for Jesus, then 78 columns are good enough for me!)
        line_width = 78
        text_width = line_width - opt_width
        big_indent = ' ' * opt_width
        if header:
            lines = [header]
        else:
            lines = ['Option summary:']

        for option in self.option_table:
            long, short, help = option[:3]
            text = wrap_text(help, text_width)
            if long[-1] == '=':
                long = long[0:-1]

            # Case 1: no short option at all (makes life easy)
            if short is None:
                if text:
                    lines.append("  --%-*s  %s" % (max_opt, long, text[0]))
                else:
                    lines.append("  --%-*s  " % (max_opt, long))

            # Case 2: we have a short option, so we have to include it
            # just after the long option
            else:
                opt_names = "%s (-%s)" % (long, short)
                if text:
                    lines.append("  --%-*s  %s" %
                                 (max_opt, opt_names, text[0]))
                else:
                    lines.append("  --%-*s" % opt_names)

            for l in text[1:]:
                lines.append(big_indent + l)

        # for self.option_table

        return lines

    # generate_help ()

    def print_help (self, header=None, file=None):
        if file is None:
            file = sys.stdout
        for line in self.generate_help(header):
            file.write(line + "\n")

# class FancyGetopt


def fancy_getopt (options, negative_opt, object, args):
    parser = FancyGetopt(options)
    parser.set_negative_aliases(negative_opt)
    return parser.getopt(args, object)


WS_TRANS = string.maketrans(string.whitespace, ' ' * len(string.whitespace))

def wrap_text (text, width):
    """wrap_text(text : string, width : int) -> [string]

    Split 'text' into multiple lines of no more than 'width' characters
    each, and return the list of strings that results.
    """

    if text is None:
        return []
    if len(text) <= width:
        return [text]

    text = string.expandtabs(text)
    text = string.translate(text, WS_TRANS)
    chunks = re.split(r'( +|-+)', text)
    chunks = filter(None, chunks)      # ' - ' results in empty strings
    lines = []

    while chunks:

        cur_line = []                   # list of chunks (to-be-joined)
        cur_len = 0                     # length of current line

        while chunks:
            l = len(chunks[0])
            if cur_len + l <= width:    # can squeeze (at least) this chunk in
                cur_line.append(chunks[0])
                del chunks[0]
                cur_len = cur_len + l
            else:                       # this line is full
                # drop last chunk if all space
                if cur_line and cur_line[-1][0] == ' ':
                    del cur_line[-1]
                break

        if chunks:                      # any chunks left to process?

            # if the current line is still empty, then we had a single
            # chunk that's too big too fit on a line -- so we break
            # down and break it up at the line width
            if cur_len == 0:
                cur_line.append(chunks[0][0:width])
                chunks[0] = chunks[0][width:]

            # all-whitespace chunks at the end of a line can be discarded
            # (and we know from the re.split above that if a chunk has
            # *any* whitespace, it is *all* whitespace)
            if chunks[0][0] == ' ':
                del chunks[0]

        # and store this line in the list-of-all-lines -- as a single
        # string, of course!
        lines.append(string.join(cur_line, ''))

    # while chunks

    return lines

# wrap_text ()


def translate_longopt (opt):
    """Convert a long option name to a valid Python identifier by
    changing "-" to "_".
    """
    return string.translate(opt, longopt_xlate)


class OptionDummy:
    """Dummy class just used as a place to hold command-line option
    values as instance attributes."""

    def __init__ (self, options=[]):
        """Create a new OptionDummy instance.  The attributes listed in
        'options' will be initialized to None."""
        for opt in options:
            setattr(self, opt, None)

# class OptionDummy


if __name__ == "__main__":
    text = """\
Tra-la-la, supercalifragilisticexpialidocious.
How *do* you spell that odd word, anyways?
(Someone ask Mary -- she'll know [or she'll
say, "How should I know?"].)"""

    for w in (10, 20, 30, 40):
        print "width: %d" % w
        print string.join(wrap_text(text, w), "\n")
        print