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1 | """distutils.fancy_getopt |
2 | ||
3 | Wrapper around the standard getopt module that provides the following | |
4 | additional features: | |
5 | * short and long options are tied together | |
6 | * options have help strings, so fancy_getopt could potentially | |
7 | create a complete usage summary | |
8 | * options set attributes of a passed-in object | |
9 | """ | |
10 | ||
11 | # This module should be kept compatible with Python 1.5.2. | |
12 | ||
13 | __revision__ = "$Id$" | |
14 | ||
15 | import sys, string, re | |
16 | from types import * | |
17 | import getopt | |
18 | from distutils.errors import * | |
19 | ||
20 | # Much like command_re in distutils.core, this is close to but not quite | |
21 | # the same as a Python NAME -- except, in the spirit of most GNU | |
22 | # utilities, we use '-' in place of '_'. (The spirit of LISP lives on!) | |
23 | # The similarities to NAME are again not a coincidence... | |
24 | longopt_pat = r'[a-zA-Z](?:[a-zA-Z0-9-]*)' | |
25 | longopt_re = re.compile(r'^%s$' % longopt_pat) | |
26 | ||
27 | # For recognizing "negative alias" options, eg. "quiet=!verbose" | |
28 | neg_alias_re = re.compile("^(%s)=!(%s)$" % (longopt_pat, longopt_pat)) | |
29 | ||
30 | # This is used to translate long options to legitimate Python identifiers | |
31 | # (for use as attributes of some object). | |
32 | longopt_xlate = string.maketrans('-', '_') | |
33 | ||
34 | class FancyGetopt: | |
35 | """Wrapper around the standard 'getopt()' module that provides some | |
36 | handy extra functionality: | |
37 | * short and long options are tied together | |
38 | * options have help strings, and help text can be assembled | |
39 | from them | |
40 | * options set attributes of a passed-in object | |
41 | * boolean options can have "negative aliases" -- eg. if | |
42 | --quiet is the "negative alias" of --verbose, then "--quiet" | |
43 | on the command line sets 'verbose' to false | |
44 | """ | |
45 | ||
46 | def __init__ (self, option_table=None): | |
47 | ||
48 | # The option table is (currently) a list of 3-tuples: | |
49 | # (long_option, short_option, help_string) | |
50 | # if an option takes an argument, its long_option should have '=' | |
51 | # appended; short_option should just be a single character, no ':' | |
52 | # in any case. If a long_option doesn't have a corresponding | |
53 | # short_option, short_option should be None. All option tuples | |
54 | # must have long options. | |
55 | self.option_table = option_table | |
56 | ||
57 | # 'option_index' maps long option names to entries in the option | |
58 | # table (ie. those 3-tuples). | |
59 | self.option_index = {} | |
60 | if self.option_table: | |
61 | self._build_index() | |
62 | ||
63 | # 'alias' records (duh) alias options; {'foo': 'bar'} means | |
64 | # --foo is an alias for --bar | |
65 | self.alias = {} | |
66 | ||
67 | # 'negative_alias' keeps track of options that are the boolean | |
68 | # opposite of some other option | |
69 | self.negative_alias = {} | |
70 | ||
71 | # These keep track of the information in the option table. We | |
72 | # don't actually populate these structures until we're ready to | |
73 | # parse the command-line, since the 'option_table' passed in here | |
74 | # isn't necessarily the final word. | |
75 | self.short_opts = [] | |
76 | self.long_opts = [] | |
77 | self.short2long = {} | |
78 | self.attr_name = {} | |
79 | self.takes_arg = {} | |
80 | ||
81 | # And 'option_order' is filled up in 'getopt()'; it records the | |
82 | # original order of options (and their values) on the command-line, | |
83 | # but expands short options, converts aliases, etc. | |
84 | self.option_order = [] | |
85 | ||
86 | # __init__ () | |
87 | ||
88 | ||
89 | def _build_index (self): | |
90 | self.option_index.clear() | |
91 | for option in self.option_table: | |
92 | self.option_index[option[0]] = option | |
93 | ||
94 | def set_option_table (self, option_table): | |
95 | self.option_table = option_table | |
96 | self._build_index() | |
97 | ||
98 | def add_option (self, long_option, short_option=None, help_string=None): | |
99 | if self.option_index.has_key(long_option): | |
100 | raise DistutilsGetoptError, \ | |
101 | "option conflict: already an option '%s'" % long_option | |
102 | else: | |
103 | option = (long_option, short_option, help_string) | |
104 | self.option_table.append(option) | |
105 | self.option_index[long_option] = option | |
106 | ||
107 | ||
108 | def has_option (self, long_option): | |
109 | """Return true if the option table for this parser has an | |
110 | option with long name 'long_option'.""" | |
111 | return self.option_index.has_key(long_option) | |
112 | ||
113 | def get_attr_name (self, long_option): | |
114 | """Translate long option name 'long_option' to the form it | |
115 | has as an attribute of some object: ie., translate hyphens | |
116 | to underscores.""" | |
117 | return string.translate(long_option, longopt_xlate) | |
118 | ||
119 | ||
120 | def _check_alias_dict (self, aliases, what): | |
121 | assert type(aliases) is DictionaryType | |
122 | for (alias, opt) in aliases.items(): | |
123 | if not self.option_index.has_key(alias): | |
124 | raise DistutilsGetoptError, \ | |
125 | ("invalid %s '%s': " | |
126 | "option '%s' not defined") % (what, alias, alias) | |
127 | if not self.option_index.has_key(opt): | |
128 | raise DistutilsGetoptError, \ | |
129 | ("invalid %s '%s': " | |
130 | "aliased option '%s' not defined") % (what, alias, opt) | |
131 | ||
132 | def set_aliases (self, alias): | |
133 | """Set the aliases for this option parser.""" | |
134 | self._check_alias_dict(alias, "alias") | |
135 | self.alias = alias | |
136 | ||
137 | def set_negative_aliases (self, negative_alias): | |
138 | """Set the negative aliases for this option parser. | |
139 | 'negative_alias' should be a dictionary mapping option names to | |
140 | option names, both the key and value must already be defined | |
141 | in the option table.""" | |
142 | self._check_alias_dict(negative_alias, "negative alias") | |
143 | self.negative_alias = negative_alias | |
144 | ||
145 | ||
146 | def _grok_option_table (self): | |
147 | """Populate the various data structures that keep tabs on the | |
148 | option table. Called by 'getopt()' before it can do anything | |
149 | worthwhile. | |
150 | """ | |
151 | self.long_opts = [] | |
152 | self.short_opts = [] | |
153 | self.short2long.clear() | |
154 | self.repeat = {} | |
155 | ||
156 | for option in self.option_table: | |
157 | if len(option) == 3: | |
158 | long, short, help = option | |
159 | repeat = 0 | |
160 | elif len(option) == 4: | |
161 | long, short, help, repeat = option | |
162 | else: | |
163 | # the option table is part of the code, so simply | |
164 | # assert that it is correct | |
165 | assert "invalid option tuple: %s" % `option` | |
166 | ||
167 | # Type- and value-check the option names | |
168 | if type(long) is not StringType or len(long) < 2: | |
169 | raise DistutilsGetoptError, \ | |
170 | ("invalid long option '%s': " | |
171 | "must be a string of length >= 2") % long | |
172 | ||
173 | if (not ((short is None) or | |
174 | (type(short) is StringType and len(short) == 1))): | |
175 | raise DistutilsGetoptError, \ | |
176 | ("invalid short option '%s': " | |
177 | "must a single character or None") % short | |
178 | ||
179 | self.repeat[long] = repeat | |
180 | self.long_opts.append(long) | |
181 | ||
182 | if long[-1] == '=': # option takes an argument? | |
183 | if short: short = short + ':' | |
184 | long = long[0:-1] | |
185 | self.takes_arg[long] = 1 | |
186 | else: | |
187 | ||
188 | # Is option is a "negative alias" for some other option (eg. | |
189 | # "quiet" == "!verbose")? | |
190 | alias_to = self.negative_alias.get(long) | |
191 | if alias_to is not None: | |
192 | if self.takes_arg[alias_to]: | |
193 | raise DistutilsGetoptError, \ | |
194 | ("invalid negative alias '%s': " | |
195 | "aliased option '%s' takes a value") % \ | |
196 | (long, alias_to) | |
197 | ||
198 | self.long_opts[-1] = long # XXX redundant?! | |
199 | self.takes_arg[long] = 0 | |
200 | ||
201 | else: | |
202 | self.takes_arg[long] = 0 | |
203 | ||
204 | # If this is an alias option, make sure its "takes arg" flag is | |
205 | # the same as the option it's aliased to. | |
206 | alias_to = self.alias.get(long) | |
207 | if alias_to is not None: | |
208 | if self.takes_arg[long] != self.takes_arg[alias_to]: | |
209 | raise DistutilsGetoptError, \ | |
210 | ("invalid alias '%s': inconsistent with " | |
211 | "aliased option '%s' (one of them takes a value, " | |
212 | "the other doesn't") % (long, alias_to) | |
213 | ||
214 | ||
215 | # Now enforce some bondage on the long option name, so we can | |
216 | # later translate it to an attribute name on some object. Have | |
217 | # to do this a bit late to make sure we've removed any trailing | |
218 | # '='. | |
219 | if not longopt_re.match(long): | |
220 | raise DistutilsGetoptError, \ | |
221 | ("invalid long option name '%s' " + | |
222 | "(must be letters, numbers, hyphens only") % long | |
223 | ||
224 | self.attr_name[long] = self.get_attr_name(long) | |
225 | if short: | |
226 | self.short_opts.append(short) | |
227 | self.short2long[short[0]] = long | |
228 | ||
229 | # for option_table | |
230 | ||
231 | # _grok_option_table() | |
232 | ||
233 | ||
234 | def getopt (self, args=None, object=None): | |
235 | """Parse command-line options in args. Store as attributes on object. | |
236 | ||
237 | If 'args' is None or not supplied, uses 'sys.argv[1:]'. If | |
238 | 'object' is None or not supplied, creates a new OptionDummy | |
239 | object, stores option values there, and returns a tuple (args, | |
240 | object). If 'object' is supplied, it is modified in place and | |
241 | 'getopt()' just returns 'args'; in both cases, the returned | |
242 | 'args' is a modified copy of the passed-in 'args' list, which | |
243 | is left untouched. | |
244 | """ | |
245 | if args is None: | |
246 | args = sys.argv[1:] | |
247 | if object is None: | |
248 | object = OptionDummy() | |
249 | created_object = 1 | |
250 | else: | |
251 | created_object = 0 | |
252 | ||
253 | self._grok_option_table() | |
254 | ||
255 | short_opts = string.join(self.short_opts) | |
256 | try: | |
257 | opts, args = getopt.getopt(args, short_opts, self.long_opts) | |
258 | except getopt.error, msg: | |
259 | raise DistutilsArgError, msg | |
260 | ||
261 | for opt, val in opts: | |
262 | if len(opt) == 2 and opt[0] == '-': # it's a short option | |
263 | opt = self.short2long[opt[1]] | |
264 | else: | |
265 | assert len(opt) > 2 and opt[:2] == '--' | |
266 | opt = opt[2:] | |
267 | ||
268 | alias = self.alias.get(opt) | |
269 | if alias: | |
270 | opt = alias | |
271 | ||
272 | if not self.takes_arg[opt]: # boolean option? | |
273 | assert val == '', "boolean option can't have value" | |
274 | alias = self.negative_alias.get(opt) | |
275 | if alias: | |
276 | opt = alias | |
277 | val = 0 | |
278 | else: | |
279 | val = 1 | |
280 | ||
281 | attr = self.attr_name[opt] | |
282 | # The only repeating option at the moment is 'verbose'. | |
283 | # It has a negative option -q quiet, which should set verbose = 0. | |
284 | if val and self.repeat.get(attr) is not None: | |
285 | val = getattr(object, attr, 0) + 1 | |
286 | setattr(object, attr, val) | |
287 | self.option_order.append((opt, val)) | |
288 | ||
289 | # for opts | |
290 | if created_object: | |
291 | return args, object | |
292 | else: | |
293 | return args | |
294 | ||
295 | # getopt() | |
296 | ||
297 | ||
298 | def get_option_order (self): | |
299 | """Returns the list of (option, value) tuples processed by the | |
300 | previous run of 'getopt()'. Raises RuntimeError if | |
301 | 'getopt()' hasn't been called yet. | |
302 | """ | |
303 | if self.option_order is None: | |
304 | raise RuntimeError, "'getopt()' hasn't been called yet" | |
305 | else: | |
306 | return self.option_order | |
307 | ||
308 | ||
309 | def generate_help (self, header=None): | |
310 | """Generate help text (a list of strings, one per suggested line of | |
311 | output) from the option table for this FancyGetopt object. | |
312 | """ | |
313 | # Blithely assume the option table is good: probably wouldn't call | |
314 | # 'generate_help()' unless you've already called 'getopt()'. | |
315 | ||
316 | # First pass: determine maximum length of long option names | |
317 | max_opt = 0 | |
318 | for option in self.option_table: | |
319 | long = option[0] | |
320 | short = option[1] | |
321 | l = len(long) | |
322 | if long[-1] == '=': | |
323 | l = l - 1 | |
324 | if short is not None: | |
325 | l = l + 5 # " (-x)" where short == 'x' | |
326 | if l > max_opt: | |
327 | max_opt = l | |
328 | ||
329 | opt_width = max_opt + 2 + 2 + 2 # room for indent + dashes + gutter | |
330 | ||
331 | # Typical help block looks like this: | |
332 | # --foo controls foonabulation | |
333 | # Help block for longest option looks like this: | |
334 | # --flimflam set the flim-flam level | |
335 | # and with wrapped text: | |
336 | # --flimflam set the flim-flam level (must be between | |
337 | # 0 and 100, except on Tuesdays) | |
338 | # Options with short names will have the short name shown (but | |
339 | # it doesn't contribute to max_opt): | |
340 | # --foo (-f) controls foonabulation | |
341 | # If adding the short option would make the left column too wide, | |
342 | # we push the explanation off to the next line | |
343 | # --flimflam (-l) | |
344 | # set the flim-flam level | |
345 | # Important parameters: | |
346 | # - 2 spaces before option block start lines | |
347 | # - 2 dashes for each long option name | |
348 | # - min. 2 spaces between option and explanation (gutter) | |
349 | # - 5 characters (incl. space) for short option name | |
350 | ||
351 | # Now generate lines of help text. (If 80 columns were good enough | |
352 | # for Jesus, then 78 columns are good enough for me!) | |
353 | line_width = 78 | |
354 | text_width = line_width - opt_width | |
355 | big_indent = ' ' * opt_width | |
356 | if header: | |
357 | lines = [header] | |
358 | else: | |
359 | lines = ['Option summary:'] | |
360 | ||
361 | for option in self.option_table: | |
362 | long, short, help = option[:3] | |
363 | text = wrap_text(help, text_width) | |
364 | if long[-1] == '=': | |
365 | long = long[0:-1] | |
366 | ||
367 | # Case 1: no short option at all (makes life easy) | |
368 | if short is None: | |
369 | if text: | |
370 | lines.append(" --%-*s %s" % (max_opt, long, text[0])) | |
371 | else: | |
372 | lines.append(" --%-*s " % (max_opt, long)) | |
373 | ||
374 | # Case 2: we have a short option, so we have to include it | |
375 | # just after the long option | |
376 | else: | |
377 | opt_names = "%s (-%s)" % (long, short) | |
378 | if text: | |
379 | lines.append(" --%-*s %s" % | |
380 | (max_opt, opt_names, text[0])) | |
381 | else: | |
382 | lines.append(" --%-*s" % opt_names) | |
383 | ||
384 | for l in text[1:]: | |
385 | lines.append(big_indent + l) | |
386 | ||
387 | # for self.option_table | |
388 | ||
389 | return lines | |
390 | ||
391 | # generate_help () | |
392 | ||
393 | def print_help (self, header=None, file=None): | |
394 | if file is None: | |
395 | file = sys.stdout | |
396 | for line in self.generate_help(header): | |
397 | file.write(line + "\n") | |
398 | ||
399 | # class FancyGetopt | |
400 | ||
401 | ||
402 | def fancy_getopt (options, negative_opt, object, args): | |
403 | parser = FancyGetopt(options) | |
404 | parser.set_negative_aliases(negative_opt) | |
405 | return parser.getopt(args, object) | |
406 | ||
407 | ||
408 | WS_TRANS = string.maketrans(string.whitespace, ' ' * len(string.whitespace)) | |
409 | ||
410 | def wrap_text (text, width): | |
411 | """wrap_text(text : string, width : int) -> [string] | |
412 | ||
413 | Split 'text' into multiple lines of no more than 'width' characters | |
414 | each, and return the list of strings that results. | |
415 | """ | |
416 | ||
417 | if text is None: | |
418 | return [] | |
419 | if len(text) <= width: | |
420 | return [text] | |
421 | ||
422 | text = string.expandtabs(text) | |
423 | text = string.translate(text, WS_TRANS) | |
424 | chunks = re.split(r'( +|-+)', text) | |
425 | chunks = filter(None, chunks) # ' - ' results in empty strings | |
426 | lines = [] | |
427 | ||
428 | while chunks: | |
429 | ||
430 | cur_line = [] # list of chunks (to-be-joined) | |
431 | cur_len = 0 # length of current line | |
432 | ||
433 | while chunks: | |
434 | l = len(chunks[0]) | |
435 | if cur_len + l <= width: # can squeeze (at least) this chunk in | |
436 | cur_line.append(chunks[0]) | |
437 | del chunks[0] | |
438 | cur_len = cur_len + l | |
439 | else: # this line is full | |
440 | # drop last chunk if all space | |
441 | if cur_line and cur_line[-1][0] == ' ': | |
442 | del cur_line[-1] | |
443 | break | |
444 | ||
445 | if chunks: # any chunks left to process? | |
446 | ||
447 | # if the current line is still empty, then we had a single | |
448 | # chunk that's too big too fit on a line -- so we break | |
449 | # down and break it up at the line width | |
450 | if cur_len == 0: | |
451 | cur_line.append(chunks[0][0:width]) | |
452 | chunks[0] = chunks[0][width:] | |
453 | ||
454 | # all-whitespace chunks at the end of a line can be discarded | |
455 | # (and we know from the re.split above that if a chunk has | |
456 | # *any* whitespace, it is *all* whitespace) | |
457 | if chunks[0][0] == ' ': | |
458 | del chunks[0] | |
459 | ||
460 | # and store this line in the list-of-all-lines -- as a single | |
461 | # string, of course! | |
462 | lines.append(string.join(cur_line, '')) | |
463 | ||
464 | # while chunks | |
465 | ||
466 | return lines | |
467 | ||
468 | # wrap_text () | |
469 | ||
470 | ||
471 | def translate_longopt (opt): | |
472 | """Convert a long option name to a valid Python identifier by | |
473 | changing "-" to "_". | |
474 | """ | |
475 | return string.translate(opt, longopt_xlate) | |
476 | ||
477 | ||
478 | class OptionDummy: | |
479 | """Dummy class just used as a place to hold command-line option | |
480 | values as instance attributes.""" | |
481 | ||
482 | def __init__ (self, options=[]): | |
483 | """Create a new OptionDummy instance. The attributes listed in | |
484 | 'options' will be initialized to None.""" | |
485 | for opt in options: | |
486 | setattr(self, opt, None) | |
487 | ||
488 | # class OptionDummy | |
489 | ||
490 | ||
491 | if __name__ == "__main__": | |
492 | text = """\ | |
493 | Tra-la-la, supercalifragilisticexpialidocious. | |
494 | How *do* you spell that odd word, anyways? | |
495 | (Someone ask Mary -- she'll know [or she'll | |
496 | say, "How should I know?"].)""" | |
497 | ||
498 | for w in (10, 20, 30, 40): | |
499 | print "width: %d" % w | |
500 | print string.join(wrap_text(text, w), "\n") | |
501 |