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<ais523> ` (cd ply-3.8; python setup.py build)
author HackBot
date Wed, 23 Mar 2016 02:43:21 +0000
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1 # -----------------------------------------------------------------------------
2 # ply: lex.py
3 #
4 # Copyright (C) 2001-2015,
5 # David M. Beazley (Dabeaz LLC)
6 # All rights reserved.
7 #
8 # Redistribution and use in source and binary forms, with or without
9 # modification, are permitted provided that the following conditions are
10 # met:
11 #
12 # * Redistributions of source code must retain the above copyright notice,
13 # this list of conditions and the following disclaimer.
14 # * Redistributions in binary form must reproduce the above copyright notice,
15 # this list of conditions and the following disclaimer in the documentation
16 # and/or other materials provided with the distribution.
17 # * Neither the name of the David Beazley or Dabeaz LLC may be used to
18 # endorse or promote products derived from this software without
19 # specific prior written permission.
20 #
21 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 # -----------------------------------------------------------------------------
33
34 __version__ = '3.8'
35 __tabversion__ = '3.8'
36
37 import re
38 import sys
39 import types
40 import copy
41 import os
42 import inspect
43
44 # This tuple contains known string types
45 try:
46 # Python 2.6
47 StringTypes = (types.StringType, types.UnicodeType)
48 except AttributeError:
49 # Python 3.0
50 StringTypes = (str, bytes)
51
52 # This regular expression is used to match valid token names
53 _is_identifier = re.compile(r'^[a-zA-Z0-9_]+$')
54
55 # Exception thrown when invalid token encountered and no default error
56 # handler is defined.
57 class LexError(Exception):
58 def __init__(self, message, s):
59 self.args = (message,)
60 self.text = s
61
62
63 # Token class. This class is used to represent the tokens produced.
64 class LexToken(object):
65 def __str__(self):
66 return 'LexToken(%s,%r,%d,%d)' % (self.type, self.value, self.lineno, self.lexpos)
67
68 def __repr__(self):
69 return str(self)
70
71
72 # This object is a stand-in for a logging object created by the
73 # logging module.
74
75 class PlyLogger(object):
76 def __init__(self, f):
77 self.f = f
78
79 def critical(self, msg, *args, **kwargs):
80 self.f.write((msg % args) + '\n')
81
82 def warning(self, msg, *args, **kwargs):
83 self.f.write('WARNING: ' + (msg % args) + '\n')
84
85 def error(self, msg, *args, **kwargs):
86 self.f.write('ERROR: ' + (msg % args) + '\n')
87
88 info = critical
89 debug = critical
90
91
92 # Null logger is used when no output is generated. Does nothing.
93 class NullLogger(object):
94 def __getattribute__(self, name):
95 return self
96
97 def __call__(self, *args, **kwargs):
98 return self
99
100
101 # -----------------------------------------------------------------------------
102 # === Lexing Engine ===
103 #
104 # The following Lexer class implements the lexer runtime. There are only
105 # a few public methods and attributes:
106 #
107 # input() - Store a new string in the lexer
108 # token() - Get the next token
109 # clone() - Clone the lexer
110 #
111 # lineno - Current line number
112 # lexpos - Current position in the input string
113 # -----------------------------------------------------------------------------
114
115 class Lexer:
116 def __init__(self):
117 self.lexre = None # Master regular expression. This is a list of
118 # tuples (re, findex) where re is a compiled
119 # regular expression and findex is a list
120 # mapping regex group numbers to rules
121 self.lexretext = None # Current regular expression strings
122 self.lexstatere = {} # Dictionary mapping lexer states to master regexs
123 self.lexstateretext = {} # Dictionary mapping lexer states to regex strings
124 self.lexstaterenames = {} # Dictionary mapping lexer states to symbol names
125 self.lexstate = 'INITIAL' # Current lexer state
126 self.lexstatestack = [] # Stack of lexer states
127 self.lexstateinfo = None # State information
128 self.lexstateignore = {} # Dictionary of ignored characters for each state
129 self.lexstateerrorf = {} # Dictionary of error functions for each state
130 self.lexstateeoff = {} # Dictionary of eof functions for each state
131 self.lexreflags = 0 # Optional re compile flags
132 self.lexdata = None # Actual input data (as a string)
133 self.lexpos = 0 # Current position in input text
134 self.lexlen = 0 # Length of the input text
135 self.lexerrorf = None # Error rule (if any)
136 self.lexeoff = None # EOF rule (if any)
137 self.lextokens = None # List of valid tokens
138 self.lexignore = '' # Ignored characters
139 self.lexliterals = '' # Literal characters that can be passed through
140 self.lexmodule = None # Module
141 self.lineno = 1 # Current line number
142 self.lexoptimize = False # Optimized mode
143
144 def clone(self, object=None):
145 c = copy.copy(self)
146
147 # If the object parameter has been supplied, it means we are attaching the
148 # lexer to a new object. In this case, we have to rebind all methods in
149 # the lexstatere and lexstateerrorf tables.
150
151 if object:
152 newtab = {}
153 for key, ritem in self.lexstatere.items():
154 newre = []
155 for cre, findex in ritem:
156 newfindex = []
157 for f in findex:
158 if not f or not f[0]:
159 newfindex.append(f)
160 continue
161 newfindex.append((getattr(object, f[0].__name__), f[1]))
162 newre.append((cre, newfindex))
163 newtab[key] = newre
164 c.lexstatere = newtab
165 c.lexstateerrorf = {}
166 for key, ef in self.lexstateerrorf.items():
167 c.lexstateerrorf[key] = getattr(object, ef.__name__)
168 c.lexmodule = object
169 return c
170
171 # ------------------------------------------------------------
172 # writetab() - Write lexer information to a table file
173 # ------------------------------------------------------------
174 def writetab(self, lextab, outputdir=''):
175 if isinstance(lextab, types.ModuleType):
176 raise IOError("Won't overwrite existing lextab module")
177 basetabmodule = lextab.split('.')[-1]
178 filename = os.path.join(outputdir, basetabmodule) + '.py'
179 with open(filename, 'w') as tf:
180 tf.write('# %s.py. This file automatically created by PLY (version %s). Don\'t edit!\n' % (basetabmodule, __version__))
181 tf.write('_tabversion = %s\n' % repr(__tabversion__))
182 tf.write('_lextokens = %s\n' % repr(self.lextokens))
183 tf.write('_lexreflags = %s\n' % repr(self.lexreflags))
184 tf.write('_lexliterals = %s\n' % repr(self.lexliterals))
185 tf.write('_lexstateinfo = %s\n' % repr(self.lexstateinfo))
186
187 # Rewrite the lexstatere table, replacing function objects with function names
188 tabre = {}
189 for statename, lre in self.lexstatere.items():
190 titem = []
191 for (pat, func), retext, renames in zip(lre, self.lexstateretext[statename], self.lexstaterenames[statename]):
192 titem.append((retext, _funcs_to_names(func, renames)))
193 tabre[statename] = titem
194
195 tf.write('_lexstatere = %s\n' % repr(tabre))
196 tf.write('_lexstateignore = %s\n' % repr(self.lexstateignore))
197
198 taberr = {}
199 for statename, ef in self.lexstateerrorf.items():
200 taberr[statename] = ef.__name__ if ef else None
201 tf.write('_lexstateerrorf = %s\n' % repr(taberr))
202
203 tabeof = {}
204 for statename, ef in self.lexstateeoff.items():
205 tabeof[statename] = ef.__name__ if ef else None
206 tf.write('_lexstateeoff = %s\n' % repr(tabeof))
207
208 # ------------------------------------------------------------
209 # readtab() - Read lexer information from a tab file
210 # ------------------------------------------------------------
211 def readtab(self, tabfile, fdict):
212 if isinstance(tabfile, types.ModuleType):
213 lextab = tabfile
214 else:
215 exec('import %s' % tabfile)
216 lextab = sys.modules[tabfile]
217
218 if getattr(lextab, '_tabversion', '0.0') != __tabversion__:
219 raise ImportError('Inconsistent PLY version')
220
221 self.lextokens = lextab._lextokens
222 self.lexreflags = lextab._lexreflags
223 self.lexliterals = lextab._lexliterals
224 self.lextokens_all = self.lextokens | set(self.lexliterals)
225 self.lexstateinfo = lextab._lexstateinfo
226 self.lexstateignore = lextab._lexstateignore
227 self.lexstatere = {}
228 self.lexstateretext = {}
229 for statename, lre in lextab._lexstatere.items():
230 titem = []
231 txtitem = []
232 for pat, func_name in lre:
233 titem.append((re.compile(pat, lextab._lexreflags | re.VERBOSE), _names_to_funcs(func_name, fdict)))
234
235 self.lexstatere[statename] = titem
236 self.lexstateretext[statename] = txtitem
237
238 self.lexstateerrorf = {}
239 for statename, ef in lextab._lexstateerrorf.items():
240 self.lexstateerrorf[statename] = fdict[ef]
241
242 self.lexstateeoff = {}
243 for statename, ef in lextab._lexstateeoff.items():
244 self.lexstateeoff[statename] = fdict[ef]
245
246 self.begin('INITIAL')
247
248 # ------------------------------------------------------------
249 # input() - Push a new string into the lexer
250 # ------------------------------------------------------------
251 def input(self, s):
252 # Pull off the first character to see if s looks like a string
253 c = s[:1]
254 if not isinstance(c, StringTypes):
255 raise ValueError('Expected a string')
256 self.lexdata = s
257 self.lexpos = 0
258 self.lexlen = len(s)
259
260 # ------------------------------------------------------------
261 # begin() - Changes the lexing state
262 # ------------------------------------------------------------
263 def begin(self, state):
264 if state not in self.lexstatere:
265 raise ValueError('Undefined state')
266 self.lexre = self.lexstatere[state]
267 self.lexretext = self.lexstateretext[state]
268 self.lexignore = self.lexstateignore.get(state, '')
269 self.lexerrorf = self.lexstateerrorf.get(state, None)
270 self.lexeoff = self.lexstateeoff.get(state, None)
271 self.lexstate = state
272
273 # ------------------------------------------------------------
274 # push_state() - Changes the lexing state and saves old on stack
275 # ------------------------------------------------------------
276 def push_state(self, state):
277 self.lexstatestack.append(self.lexstate)
278 self.begin(state)
279
280 # ------------------------------------------------------------
281 # pop_state() - Restores the previous state
282 # ------------------------------------------------------------
283 def pop_state(self):
284 self.begin(self.lexstatestack.pop())
285
286 # ------------------------------------------------------------
287 # current_state() - Returns the current lexing state
288 # ------------------------------------------------------------
289 def current_state(self):
290 return self.lexstate
291
292 # ------------------------------------------------------------
293 # skip() - Skip ahead n characters
294 # ------------------------------------------------------------
295 def skip(self, n):
296 self.lexpos += n
297
298 # ------------------------------------------------------------
299 # opttoken() - Return the next token from the Lexer
300 #
301 # Note: This function has been carefully implemented to be as fast
302 # as possible. Don't make changes unless you really know what
303 # you are doing
304 # ------------------------------------------------------------
305 def token(self):
306 # Make local copies of frequently referenced attributes
307 lexpos = self.lexpos
308 lexlen = self.lexlen
309 lexignore = self.lexignore
310 lexdata = self.lexdata
311
312 while lexpos < lexlen:
313 # This code provides some short-circuit code for whitespace, tabs, and other ignored characters
314 if lexdata[lexpos] in lexignore:
315 lexpos += 1
316 continue
317
318 # Look for a regular expression match
319 for lexre, lexindexfunc in self.lexre:
320 m = lexre.match(lexdata, lexpos)
321 if not m:
322 continue
323
324 # Create a token for return
325 tok = LexToken()
326 tok.value = m.group()
327 tok.lineno = self.lineno
328 tok.lexpos = lexpos
329
330 i = m.lastindex
331 func, tok.type = lexindexfunc[i]
332
333 if not func:
334 # If no token type was set, it's an ignored token
335 if tok.type:
336 self.lexpos = m.end()
337 return tok
338 else:
339 lexpos = m.end()
340 break
341
342 lexpos = m.end()
343
344 # If token is processed by a function, call it
345
346 tok.lexer = self # Set additional attributes useful in token rules
347 self.lexmatch = m
348 self.lexpos = lexpos
349
350 newtok = func(tok)
351
352 # Every function must return a token, if nothing, we just move to next token
353 if not newtok:
354 lexpos = self.lexpos # This is here in case user has updated lexpos.
355 lexignore = self.lexignore # This is here in case there was a state change
356 break
357
358 # Verify type of the token. If not in the token map, raise an error
359 if not self.lexoptimize:
360 if newtok.type not in self.lextokens_all:
361 raise LexError("%s:%d: Rule '%s' returned an unknown token type '%s'" % (
362 func.__code__.co_filename, func.__code__.co_firstlineno,
363 func.__name__, newtok.type), lexdata[lexpos:])
364
365 return newtok
366 else:
367 # No match, see if in literals
368 if lexdata[lexpos] in self.lexliterals:
369 tok = LexToken()
370 tok.value = lexdata[lexpos]
371 tok.lineno = self.lineno
372 tok.type = tok.value
373 tok.lexpos = lexpos
374 self.lexpos = lexpos + 1
375 return tok
376
377 # No match. Call t_error() if defined.
378 if self.lexerrorf:
379 tok = LexToken()
380 tok.value = self.lexdata[lexpos:]
381 tok.lineno = self.lineno
382 tok.type = 'error'
383 tok.lexer = self
384 tok.lexpos = lexpos
385 self.lexpos = lexpos
386 newtok = self.lexerrorf(tok)
387 if lexpos == self.lexpos:
388 # Error method didn't change text position at all. This is an error.
389 raise LexError("Scanning error. Illegal character '%s'" % (lexdata[lexpos]), lexdata[lexpos:])
390 lexpos = self.lexpos
391 if not newtok:
392 continue
393 return newtok
394
395 self.lexpos = lexpos
396 raise LexError("Illegal character '%s' at index %d" % (lexdata[lexpos], lexpos), lexdata[lexpos:])
397
398 if self.lexeoff:
399 tok = LexToken()
400 tok.type = 'eof'
401 tok.value = ''
402 tok.lineno = self.lineno
403 tok.lexpos = lexpos
404 tok.lexer = self
405 self.lexpos = lexpos
406 newtok = self.lexeoff(tok)
407 return newtok
408
409 self.lexpos = lexpos + 1
410 if self.lexdata is None:
411 raise RuntimeError('No input string given with input()')
412 return None
413
414 # Iterator interface
415 def __iter__(self):
416 return self
417
418 def next(self):
419 t = self.token()
420 if t is None:
421 raise StopIteration
422 return t
423
424 __next__ = next
425
426 # -----------------------------------------------------------------------------
427 # ==== Lex Builder ===
428 #
429 # The functions and classes below are used to collect lexing information
430 # and build a Lexer object from it.
431 # -----------------------------------------------------------------------------
432
433 # -----------------------------------------------------------------------------
434 # _get_regex(func)
435 #
436 # Returns the regular expression assigned to a function either as a doc string
437 # or as a .regex attribute attached by the @TOKEN decorator.
438 # -----------------------------------------------------------------------------
439 def _get_regex(func):
440 return getattr(func, 'regex', func.__doc__)
441
442 # -----------------------------------------------------------------------------
443 # get_caller_module_dict()
444 #
445 # This function returns a dictionary containing all of the symbols defined within
446 # a caller further down the call stack. This is used to get the environment
447 # associated with the yacc() call if none was provided.
448 # -----------------------------------------------------------------------------
449 def get_caller_module_dict(levels):
450 f = sys._getframe(levels)
451 ldict = f.f_globals.copy()
452 if f.f_globals != f.f_locals:
453 ldict.update(f.f_locals)
454 return ldict
455
456 # -----------------------------------------------------------------------------
457 # _funcs_to_names()
458 #
459 # Given a list of regular expression functions, this converts it to a list
460 # suitable for output to a table file
461 # -----------------------------------------------------------------------------
462 def _funcs_to_names(funclist, namelist):
463 result = []
464 for f, name in zip(funclist, namelist):
465 if f and f[0]:
466 result.append((name, f[1]))
467 else:
468 result.append(f)
469 return result
470
471 # -----------------------------------------------------------------------------
472 # _names_to_funcs()
473 #
474 # Given a list of regular expression function names, this converts it back to
475 # functions.
476 # -----------------------------------------------------------------------------
477 def _names_to_funcs(namelist, fdict):
478 result = []
479 for n in namelist:
480 if n and n[0]:
481 result.append((fdict[n[0]], n[1]))
482 else:
483 result.append(n)
484 return result
485
486 # -----------------------------------------------------------------------------
487 # _form_master_re()
488 #
489 # This function takes a list of all of the regex components and attempts to
490 # form the master regular expression. Given limitations in the Python re
491 # module, it may be necessary to break the master regex into separate expressions.
492 # -----------------------------------------------------------------------------
493 def _form_master_re(relist, reflags, ldict, toknames):
494 if not relist:
495 return []
496 regex = '|'.join(relist)
497 try:
498 lexre = re.compile(regex, re.VERBOSE | reflags)
499
500 # Build the index to function map for the matching engine
501 lexindexfunc = [None] * (max(lexre.groupindex.values()) + 1)
502 lexindexnames = lexindexfunc[:]
503
504 for f, i in lexre.groupindex.items():
505 handle = ldict.get(f, None)
506 if type(handle) in (types.FunctionType, types.MethodType):
507 lexindexfunc[i] = (handle, toknames[f])
508 lexindexnames[i] = f
509 elif handle is not None:
510 lexindexnames[i] = f
511 if f.find('ignore_') > 0:
512 lexindexfunc[i] = (None, None)
513 else:
514 lexindexfunc[i] = (None, toknames[f])
515
516 return [(lexre, lexindexfunc)], [regex], [lexindexnames]
517 except Exception:
518 m = int(len(relist)/2)
519 if m == 0:
520 m = 1
521 llist, lre, lnames = _form_master_re(relist[:m], reflags, ldict, toknames)
522 rlist, rre, rnames = _form_master_re(relist[m:], reflags, ldict, toknames)
523 return (llist+rlist), (lre+rre), (lnames+rnames)
524
525 # -----------------------------------------------------------------------------
526 # def _statetoken(s,names)
527 #
528 # Given a declaration name s of the form "t_" and a dictionary whose keys are
529 # state names, this function returns a tuple (states,tokenname) where states
530 # is a tuple of state names and tokenname is the name of the token. For example,
531 # calling this with s = "t_foo_bar_SPAM" might return (('foo','bar'),'SPAM')
532 # -----------------------------------------------------------------------------
533 def _statetoken(s, names):
534 nonstate = 1
535 parts = s.split('_')
536 for i, part in enumerate(parts[1:], 1):
537 if part not in names and part != 'ANY':
538 break
539
540 if i > 1:
541 states = tuple(parts[1:i])
542 else:
543 states = ('INITIAL',)
544
545 if 'ANY' in states:
546 states = tuple(names)
547
548 tokenname = '_'.join(parts[i:])
549 return (states, tokenname)
550
551
552 # -----------------------------------------------------------------------------
553 # LexerReflect()
554 #
555 # This class represents information needed to build a lexer as extracted from a
556 # user's input file.
557 # -----------------------------------------------------------------------------
558 class LexerReflect(object):
559 def __init__(self, ldict, log=None, reflags=0):
560 self.ldict = ldict
561 self.error_func = None
562 self.tokens = []
563 self.reflags = reflags
564 self.stateinfo = {'INITIAL': 'inclusive'}
565 self.modules = set()
566 self.error = False
567 self.log = PlyLogger(sys.stderr) if log is None else log
568
569 # Get all of the basic information
570 def get_all(self):
571 self.get_tokens()
572 self.get_literals()
573 self.get_states()
574 self.get_rules()
575
576 # Validate all of the information
577 def validate_all(self):
578 self.validate_tokens()
579 self.validate_literals()
580 self.validate_rules()
581 return self.error
582
583 # Get the tokens map
584 def get_tokens(self):
585 tokens = self.ldict.get('tokens', None)
586 if not tokens:
587 self.log.error('No token list is defined')
588 self.error = True
589 return
590
591 if not isinstance(tokens, (list, tuple)):
592 self.log.error('tokens must be a list or tuple')
593 self.error = True
594 return
595
596 if not tokens:
597 self.log.error('tokens is empty')
598 self.error = True
599 return
600
601 self.tokens = tokens
602
603 # Validate the tokens
604 def validate_tokens(self):
605 terminals = {}
606 for n in self.tokens:
607 if not _is_identifier.match(n):
608 self.log.error("Bad token name '%s'", n)
609 self.error = True
610 if n in terminals:
611 self.log.warning("Token '%s' multiply defined", n)
612 terminals[n] = 1
613
614 # Get the literals specifier
615 def get_literals(self):
616 self.literals = self.ldict.get('literals', '')
617 if not self.literals:
618 self.literals = ''
619
620 # Validate literals
621 def validate_literals(self):
622 try:
623 for c in self.literals:
624 if not isinstance(c, StringTypes) or len(c) > 1:
625 self.log.error('Invalid literal %s. Must be a single character', repr(c))
626 self.error = True
627
628 except TypeError:
629 self.log.error('Invalid literals specification. literals must be a sequence of characters')
630 self.error = True
631
632 def get_states(self):
633 self.states = self.ldict.get('states', None)
634 # Build statemap
635 if self.states:
636 if not isinstance(self.states, (tuple, list)):
637 self.log.error('states must be defined as a tuple or list')
638 self.error = True
639 else:
640 for s in self.states:
641 if not isinstance(s, tuple) or len(s) != 2:
642 self.log.error("Invalid state specifier %s. Must be a tuple (statename,'exclusive|inclusive')", repr(s))
643 self.error = True
644 continue
645 name, statetype = s
646 if not isinstance(name, StringTypes):
647 self.log.error('State name %s must be a string', repr(name))
648 self.error = True
649 continue
650 if not (statetype == 'inclusive' or statetype == 'exclusive'):
651 self.log.error("State type for state %s must be 'inclusive' or 'exclusive'", name)
652 self.error = True
653 continue
654 if name in self.stateinfo:
655 self.log.error("State '%s' already defined", name)
656 self.error = True
657 continue
658 self.stateinfo[name] = statetype
659
660 # Get all of the symbols with a t_ prefix and sort them into various
661 # categories (functions, strings, error functions, and ignore characters)
662
663 def get_rules(self):
664 tsymbols = [f for f in self.ldict if f[:2] == 't_']
665
666 # Now build up a list of functions and a list of strings
667 self.toknames = {} # Mapping of symbols to token names
668 self.funcsym = {} # Symbols defined as functions
669 self.strsym = {} # Symbols defined as strings
670 self.ignore = {} # Ignore strings by state
671 self.errorf = {} # Error functions by state
672 self.eoff = {} # EOF functions by state
673
674 for s in self.stateinfo:
675 self.funcsym[s] = []
676 self.strsym[s] = []
677
678 if len(tsymbols) == 0:
679 self.log.error('No rules of the form t_rulename are defined')
680 self.error = True
681 return
682
683 for f in tsymbols:
684 t = self.ldict[f]
685 states, tokname = _statetoken(f, self.stateinfo)
686 self.toknames[f] = tokname
687
688 if hasattr(t, '__call__'):
689 if tokname == 'error':
690 for s in states:
691 self.errorf[s] = t
692 elif tokname == 'eof':
693 for s in states:
694 self.eoff[s] = t
695 elif tokname == 'ignore':
696 line = t.__code__.co_firstlineno
697 file = t.__code__.co_filename
698 self.log.error("%s:%d: Rule '%s' must be defined as a string", file, line, t.__name__)
699 self.error = True
700 else:
701 for s in states:
702 self.funcsym[s].append((f, t))
703 elif isinstance(t, StringTypes):
704 if tokname == 'ignore':
705 for s in states:
706 self.ignore[s] = t
707 if '\\' in t:
708 self.log.warning("%s contains a literal backslash '\\'", f)
709
710 elif tokname == 'error':
711 self.log.error("Rule '%s' must be defined as a function", f)
712 self.error = True
713 else:
714 for s in states:
715 self.strsym[s].append((f, t))
716 else:
717 self.log.error('%s not defined as a function or string', f)
718 self.error = True
719
720 # Sort the functions by line number
721 for f in self.funcsym.values():
722 f.sort(key=lambda x: x[1].__code__.co_firstlineno)
723
724 # Sort the strings by regular expression length
725 for s in self.strsym.values():
726 s.sort(key=lambda x: len(x[1]), reverse=True)
727
728 # Validate all of the t_rules collected
729 def validate_rules(self):
730 for state in self.stateinfo:
731 # Validate all rules defined by functions
732
733 for fname, f in self.funcsym[state]:
734 line = f.__code__.co_firstlineno
735 file = f.__code__.co_filename
736 module = inspect.getmodule(f)
737 self.modules.add(module)
738
739 tokname = self.toknames[fname]
740 if isinstance(f, types.MethodType):
741 reqargs = 2
742 else:
743 reqargs = 1
744 nargs = f.__code__.co_argcount
745 if nargs > reqargs:
746 self.log.error("%s:%d: Rule '%s' has too many arguments", file, line, f.__name__)
747 self.error = True
748 continue
749
750 if nargs < reqargs:
751 self.log.error("%s:%d: Rule '%s' requires an argument", file, line, f.__name__)
752 self.error = True
753 continue
754
755 if not _get_regex(f):
756 self.log.error("%s:%d: No regular expression defined for rule '%s'", file, line, f.__name__)
757 self.error = True
758 continue
759
760 try:
761 c = re.compile('(?P<%s>%s)' % (fname, _get_regex(f)), re.VERBOSE | self.reflags)
762 if c.match(''):
763 self.log.error("%s:%d: Regular expression for rule '%s' matches empty string", file, line, f.__name__)
764 self.error = True
765 except re.error as e:
766 self.log.error("%s:%d: Invalid regular expression for rule '%s'. %s", file, line, f.__name__, e)
767 if '#' in _get_regex(f):
768 self.log.error("%s:%d. Make sure '#' in rule '%s' is escaped with '\\#'", file, line, f.__name__)
769 self.error = True
770
771 # Validate all rules defined by strings
772 for name, r in self.strsym[state]:
773 tokname = self.toknames[name]
774 if tokname == 'error':
775 self.log.error("Rule '%s' must be defined as a function", name)
776 self.error = True
777 continue
778
779 if tokname not in self.tokens and tokname.find('ignore_') < 0:
780 self.log.error("Rule '%s' defined for an unspecified token %s", name, tokname)
781 self.error = True
782 continue
783
784 try:
785 c = re.compile('(?P<%s>%s)' % (name, r), re.VERBOSE | self.reflags)
786 if (c.match('')):
787 self.log.error("Regular expression for rule '%s' matches empty string", name)
788 self.error = True
789 except re.error as e:
790 self.log.error("Invalid regular expression for rule '%s'. %s", name, e)
791 if '#' in r:
792 self.log.error("Make sure '#' in rule '%s' is escaped with '\\#'", name)
793 self.error = True
794
795 if not self.funcsym[state] and not self.strsym[state]:
796 self.log.error("No rules defined for state '%s'", state)
797 self.error = True
798
799 # Validate the error function
800 efunc = self.errorf.get(state, None)
801 if efunc:
802 f = efunc
803 line = f.__code__.co_firstlineno
804 file = f.__code__.co_filename
805 module = inspect.getmodule(f)
806 self.modules.add(module)
807
808 if isinstance(f, types.MethodType):
809 reqargs = 2
810 else:
811 reqargs = 1
812 nargs = f.__code__.co_argcount
813 if nargs > reqargs:
814 self.log.error("%s:%d: Rule '%s' has too many arguments", file, line, f.__name__)
815 self.error = True
816
817 if nargs < reqargs:
818 self.log.error("%s:%d: Rule '%s' requires an argument", file, line, f.__name__)
819 self.error = True
820
821 for module in self.modules:
822 self.validate_module(module)
823
824 # -----------------------------------------------------------------------------
825 # validate_module()
826 #
827 # This checks to see if there are duplicated t_rulename() functions or strings
828 # in the parser input file. This is done using a simple regular expression
829 # match on each line in the source code of the given module.
830 # -----------------------------------------------------------------------------
831
832 def validate_module(self, module):
833 lines, linen = inspect.getsourcelines(module)
834
835 fre = re.compile(r'\s*def\s+(t_[a-zA-Z_0-9]*)\(')
836 sre = re.compile(r'\s*(t_[a-zA-Z_0-9]*)\s*=')
837
838 counthash = {}
839 linen += 1
840 for line in lines:
841 m = fre.match(line)
842 if not m:
843 m = sre.match(line)
844 if m:
845 name = m.group(1)
846 prev = counthash.get(name)
847 if not prev:
848 counthash[name] = linen
849 else:
850 filename = inspect.getsourcefile(module)
851 self.log.error('%s:%d: Rule %s redefined. Previously defined on line %d', filename, linen, name, prev)
852 self.error = True
853 linen += 1
854
855 # -----------------------------------------------------------------------------
856 # lex(module)
857 #
858 # Build all of the regular expression rules from definitions in the supplied module
859 # -----------------------------------------------------------------------------
860 def lex(module=None, object=None, debug=False, optimize=False, lextab='lextab',
861 reflags=0, nowarn=False, outputdir=None, debuglog=None, errorlog=None):
862
863 if lextab is None:
864 lextab = 'lextab'
865
866 global lexer
867
868 ldict = None
869 stateinfo = {'INITIAL': 'inclusive'}
870 lexobj = Lexer()
871 lexobj.lexoptimize = optimize
872 global token, input
873
874 if errorlog is None:
875 errorlog = PlyLogger(sys.stderr)
876
877 if debug:
878 if debuglog is None:
879 debuglog = PlyLogger(sys.stderr)
880
881 # Get the module dictionary used for the lexer
882 if object:
883 module = object
884
885 # Get the module dictionary used for the parser
886 if module:
887 _items = [(k, getattr(module, k)) for k in dir(module)]
888 ldict = dict(_items)
889 # If no __file__ attribute is available, try to obtain it from the __module__ instead
890 if '__file__' not in ldict:
891 ldict['__file__'] = sys.modules[ldict['__module__']].__file__
892 else:
893 ldict = get_caller_module_dict(2)
894
895 # Determine if the module is package of a package or not.
896 # If so, fix the tabmodule setting so that tables load correctly
897 pkg = ldict.get('__package__')
898 if pkg and isinstance(lextab, str):
899 if '.' not in lextab:
900 lextab = pkg + '.' + lextab
901
902 # Collect parser information from the dictionary
903 linfo = LexerReflect(ldict, log=errorlog, reflags=reflags)
904 linfo.get_all()
905 if not optimize:
906 if linfo.validate_all():
907 raise SyntaxError("Can't build lexer")
908
909 if optimize and lextab:
910 try:
911 lexobj.readtab(lextab, ldict)
912 token = lexobj.token
913 input = lexobj.input
914 lexer = lexobj
915 return lexobj
916
917 except ImportError:
918 pass
919
920 # Dump some basic debugging information
921 if debug:
922 debuglog.info('lex: tokens = %r', linfo.tokens)
923 debuglog.info('lex: literals = %r', linfo.literals)
924 debuglog.info('lex: states = %r', linfo.stateinfo)
925
926 # Build a dictionary of valid token names
927 lexobj.lextokens = set()
928 for n in linfo.tokens:
929 lexobj.lextokens.add(n)
930
931 # Get literals specification
932 if isinstance(linfo.literals, (list, tuple)):
933 lexobj.lexliterals = type(linfo.literals[0])().join(linfo.literals)
934 else:
935 lexobj.lexliterals = linfo.literals
936
937 lexobj.lextokens_all = lexobj.lextokens | set(lexobj.lexliterals)
938
939 # Get the stateinfo dictionary
940 stateinfo = linfo.stateinfo
941
942 regexs = {}
943 # Build the master regular expressions
944 for state in stateinfo:
945 regex_list = []
946
947 # Add rules defined by functions first
948 for fname, f in linfo.funcsym[state]:
949 line = f.__code__.co_firstlineno
950 file = f.__code__.co_filename
951 regex_list.append('(?P<%s>%s)' % (fname, _get_regex(f)))
952 if debug:
953 debuglog.info("lex: Adding rule %s -> '%s' (state '%s')", fname, _get_regex(f), state)
954
955 # Now add all of the simple rules
956 for name, r in linfo.strsym[state]:
957 regex_list.append('(?P<%s>%s)' % (name, r))
958 if debug:
959 debuglog.info("lex: Adding rule %s -> '%s' (state '%s')", name, r, state)
960
961 regexs[state] = regex_list
962
963 # Build the master regular expressions
964
965 if debug:
966 debuglog.info('lex: ==== MASTER REGEXS FOLLOW ====')
967
968 for state in regexs:
969 lexre, re_text, re_names = _form_master_re(regexs[state], reflags, ldict, linfo.toknames)
970 lexobj.lexstatere[state] = lexre
971 lexobj.lexstateretext[state] = re_text
972 lexobj.lexstaterenames[state] = re_names
973 if debug:
974 for i, text in enumerate(re_text):
975 debuglog.info("lex: state '%s' : regex[%d] = '%s'", state, i, text)
976
977 # For inclusive states, we need to add the regular expressions from the INITIAL state
978 for state, stype in stateinfo.items():
979 if state != 'INITIAL' and stype == 'inclusive':
980 lexobj.lexstatere[state].extend(lexobj.lexstatere['INITIAL'])
981 lexobj.lexstateretext[state].extend(lexobj.lexstateretext['INITIAL'])
982 lexobj.lexstaterenames[state].extend(lexobj.lexstaterenames['INITIAL'])
983
984 lexobj.lexstateinfo = stateinfo
985 lexobj.lexre = lexobj.lexstatere['INITIAL']
986 lexobj.lexretext = lexobj.lexstateretext['INITIAL']
987 lexobj.lexreflags = reflags
988
989 # Set up ignore variables
990 lexobj.lexstateignore = linfo.ignore
991 lexobj.lexignore = lexobj.lexstateignore.get('INITIAL', '')
992
993 # Set up error functions
994 lexobj.lexstateerrorf = linfo.errorf
995 lexobj.lexerrorf = linfo.errorf.get('INITIAL', None)
996 if not lexobj.lexerrorf:
997 errorlog.warning('No t_error rule is defined')
998
999 # Set up eof functions
1000 lexobj.lexstateeoff = linfo.eoff
1001 lexobj.lexeoff = linfo.eoff.get('INITIAL', None)
1002
1003 # Check state information for ignore and error rules
1004 for s, stype in stateinfo.items():
1005 if stype == 'exclusive':
1006 if s not in linfo.errorf:
1007 errorlog.warning("No error rule is defined for exclusive state '%s'", s)
1008 if s not in linfo.ignore and lexobj.lexignore:
1009 errorlog.warning("No ignore rule is defined for exclusive state '%s'", s)
1010 elif stype == 'inclusive':
1011 if s not in linfo.errorf:
1012 linfo.errorf[s] = linfo.errorf.get('INITIAL', None)
1013 if s not in linfo.ignore:
1014 linfo.ignore[s] = linfo.ignore.get('INITIAL', '')
1015
1016 # Create global versions of the token() and input() functions
1017 token = lexobj.token
1018 input = lexobj.input
1019 lexer = lexobj
1020
1021 # If in optimize mode, we write the lextab
1022 if lextab and optimize:
1023 if outputdir is None:
1024 # If no output directory is set, the location of the output files
1025 # is determined according to the following rules:
1026 # - If lextab specifies a package, files go into that package directory
1027 # - Otherwise, files go in the same directory as the specifying module
1028 if isinstance(lextab, types.ModuleType):
1029 srcfile = lextab.__file__
1030 else:
1031 if '.' not in lextab:
1032 srcfile = ldict['__file__']
1033 else:
1034 parts = lextab.split('.')
1035 pkgname = '.'.join(parts[:-1])
1036 exec('import %s' % pkgname)
1037 srcfile = getattr(sys.modules[pkgname], '__file__', '')
1038 outputdir = os.path.dirname(srcfile)
1039 try:
1040 lexobj.writetab(lextab, outputdir)
1041 except IOError as e:
1042 errorlog.warning("Couldn't write lextab module %r. %s" % (lextab, e))
1043
1044 return lexobj
1045
1046 # -----------------------------------------------------------------------------
1047 # runmain()
1048 #
1049 # This runs the lexer as a main program
1050 # -----------------------------------------------------------------------------
1051
1052 def runmain(lexer=None, data=None):
1053 if not data:
1054 try:
1055 filename = sys.argv[1]
1056 f = open(filename)
1057 data = f.read()
1058 f.close()
1059 except IndexError:
1060 sys.stdout.write('Reading from standard input (type EOF to end):\n')
1061 data = sys.stdin.read()
1062
1063 if lexer:
1064 _input = lexer.input
1065 else:
1066 _input = input
1067 _input(data)
1068 if lexer:
1069 _token = lexer.token
1070 else:
1071 _token = token
1072
1073 while True:
1074 tok = _token()
1075 if not tok:
1076 break
1077 sys.stdout.write('(%s,%r,%d,%d)\n' % (tok.type, tok.value, tok.lineno, tok.lexpos))
1078
1079 # -----------------------------------------------------------------------------
1080 # @TOKEN(regex)
1081 #
1082 # This decorator function can be used to set the regex expression on a function
1083 # when its docstring might need to be set in an alternative way
1084 # -----------------------------------------------------------------------------
1085
1086 def TOKEN(r):
1087 def set_regex(f):
1088 if hasattr(r, '__call__'):
1089 f.regex = _get_regex(r)
1090 else:
1091 f.regex = r
1092 return f
1093 return set_regex
1094
1095 # Alternative spelling of the TOKEN decorator
1096 Token = TOKEN
1097