1#!/usr/bin/env python
2#
3# Copyright 2008, Google Inc.
4# All rights reserved.
5#
6# Redistribution and use in source and binary forms, with or without
7# modification, are permitted provided that the following conditions are
8# met:
9#
10#     * Redistributions of source code must retain the above copyright
11# notice, this list of conditions and the following disclaimer.
12#     * Redistributions in binary form must reproduce the above
13# copyright notice, this list of conditions and the following disclaimer
14# in the documentation and/or other materials provided with the
15# distribution.
16#     * Neither the name of Google Inc. nor the names of its
17# contributors may be used to endorse or promote products derived from
18# this software without specific prior written permission.
19#
20# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31
32"""pump v0.2.0 - Pretty Useful for Meta Programming.
33
34A tool for preprocessor meta programming.  Useful for generating
35repetitive boilerplate code.  Especially useful for writing C++
36classes, functions, macros, and templates that need to work with
37various number of arguments.
38
39USAGE:
40       pump.py SOURCE_FILE
41
42EXAMPLES:
43       pump.py foo.cc.pump
44         Converts foo.cc.pump to foo.cc.
45
46GRAMMAR:
47       CODE ::= ATOMIC_CODE*
48       ATOMIC_CODE ::= $var ID = EXPRESSION
49           | $var ID = [[ CODE ]]
50           | $range ID EXPRESSION..EXPRESSION
51           | $for ID SEPARATOR [[ CODE ]]
52           | $($)
53           | $ID
54           | $(EXPRESSION)
55           | $if EXPRESSION [[ CODE ]] ELSE_BRANCH
56           | [[ CODE ]]
57           | RAW_CODE
58       SEPARATOR ::= RAW_CODE | EMPTY
59       ELSE_BRANCH ::= $else [[ CODE ]]
60           | $elif EXPRESSION [[ CODE ]] ELSE_BRANCH
61           | EMPTY
62       EXPRESSION has Python syntax.
63"""
64
65__author__ = 'wan@google.com (Zhanyong Wan)'
66
67import os
68import re
69import sys
70
71
72TOKEN_TABLE = [
73    (re.compile(r'\$var\s+'), '$var'),
74    (re.compile(r'\$elif\s+'), '$elif'),
75    (re.compile(r'\$else\s+'), '$else'),
76    (re.compile(r'\$for\s+'), '$for'),
77    (re.compile(r'\$if\s+'), '$if'),
78    (re.compile(r'\$range\s+'), '$range'),
79    (re.compile(r'\$[_A-Za-z]\w*'), '$id'),
80    (re.compile(r'\$\(\$\)'), '$($)'),
81    (re.compile(r'\$'), '$'),
82    (re.compile(r'\[\[\n?'), '[['),
83    (re.compile(r'\]\]\n?'), ']]'),
84    ]
85
86
87class Cursor:
88  """Represents a position (line and column) in a text file."""
89
90  def __init__(self, line=-1, column=-1):
91    self.line = line
92    self.column = column
93
94  def __eq__(self, rhs):
95    return self.line == rhs.line and self.column == rhs.column
96
97  def __ne__(self, rhs):
98    return not self == rhs
99
100  def __lt__(self, rhs):
101    return self.line < rhs.line or (
102        self.line == rhs.line and self.column < rhs.column)
103
104  def __le__(self, rhs):
105    return self < rhs or self == rhs
106
107  def __gt__(self, rhs):
108    return rhs < self
109
110  def __ge__(self, rhs):
111    return rhs <= self
112
113  def __str__(self):
114    if self == Eof():
115      return 'EOF'
116    else:
117      return '%s(%s)' % (self.line + 1, self.column)
118
119  def __add__(self, offset):
120    return Cursor(self.line, self.column + offset)
121
122  def __sub__(self, offset):
123    return Cursor(self.line, self.column - offset)
124
125  def Clone(self):
126    """Returns a copy of self."""
127
128    return Cursor(self.line, self.column)
129
130
131# Special cursor to indicate the end-of-file.
132def Eof():
133  """Returns the special cursor to denote the end-of-file."""
134  return Cursor(-1, -1)
135
136
137class Token:
138  """Represents a token in a Pump source file."""
139
140  def __init__(self, start=None, end=None, value=None, token_type=None):
141    if start is None:
142      self.start = Eof()
143    else:
144      self.start = start
145    if end is None:
146      self.end = Eof()
147    else:
148      self.end = end
149    self.value = value
150    self.token_type = token_type
151
152  def __str__(self):
153    return 'Token @%s: \'%s\' type=%s' % (
154        self.start, self.value, self.token_type)
155
156  def Clone(self):
157    """Returns a copy of self."""
158
159    return Token(self.start.Clone(), self.end.Clone(), self.value,
160                 self.token_type)
161
162
163def StartsWith(lines, pos, string):
164  """Returns True iff the given position in lines starts with 'string'."""
165
166  return lines[pos.line][pos.column:].startswith(string)
167
168
169def FindFirstInLine(line, token_table):
170  best_match_start = -1
171  for (regex, token_type) in token_table:
172    m = regex.search(line)
173    if m:
174      # We found regex in lines
175      if best_match_start < 0 or m.start() < best_match_start:
176        best_match_start = m.start()
177        best_match_length = m.end() - m.start()
178        best_match_token_type = token_type
179
180  if best_match_start < 0:
181    return None
182
183  return (best_match_start, best_match_length, best_match_token_type)
184
185
186def FindFirst(lines, token_table, cursor):
187  """Finds the first occurrence of any string in strings in lines."""
188
189  start = cursor.Clone()
190  cur_line_number = cursor.line
191  for line in lines[start.line:]:
192    if cur_line_number == start.line:
193      line = line[start.column:]
194    m = FindFirstInLine(line, token_table)
195    if m:
196      # We found a regex in line.
197      (start_column, length, token_type) = m
198      if cur_line_number == start.line:
199        start_column += start.column
200      found_start = Cursor(cur_line_number, start_column)
201      found_end = found_start + length
202      return MakeToken(lines, found_start, found_end, token_type)
203    cur_line_number += 1
204  # We failed to find str in lines
205  return None
206
207
208def SubString(lines, start, end):
209  """Returns a substring in lines."""
210
211  if end == Eof():
212    end = Cursor(len(lines) - 1, len(lines[-1]))
213
214  if start >= end:
215    return ''
216
217  if start.line == end.line:
218    return lines[start.line][start.column:end.column]
219
220  result_lines = ([lines[start.line][start.column:]] +
221                  lines[start.line + 1:end.line] +
222                  [lines[end.line][:end.column]])
223  return ''.join(result_lines)
224
225
226def StripMetaComments(str):
227  """Strip meta comments from each line in the given string."""
228
229  # First, completely remove lines containing nothing but a meta
230  # comment, including the trailing \n.
231  str = re.sub(r'^\s*\$\$.*\n', '', str)
232
233  # Then, remove meta comments from contentful lines.
234  return re.sub(r'\s*\$\$.*', '', str)
235
236
237def MakeToken(lines, start, end, token_type):
238  """Creates a new instance of Token."""
239
240  return Token(start, end, SubString(lines, start, end), token_type)
241
242
243def ParseToken(lines, pos, regex, token_type):
244  line = lines[pos.line][pos.column:]
245  m = regex.search(line)
246  if m and not m.start():
247    return MakeToken(lines, pos, pos + m.end(), token_type)
248  else:
249    print 'ERROR: %s expected at %s.' % (token_type, pos)
250    sys.exit(1)
251
252
253ID_REGEX = re.compile(r'[_A-Za-z]\w*')
254EQ_REGEX = re.compile(r'=')
255REST_OF_LINE_REGEX = re.compile(r'.*?(?=$|\$\$)')
256OPTIONAL_WHITE_SPACES_REGEX = re.compile(r'\s*')
257WHITE_SPACE_REGEX = re.compile(r'\s')
258DOT_DOT_REGEX = re.compile(r'\.\.')
259
260
261def Skip(lines, pos, regex):
262  line = lines[pos.line][pos.column:]
263  m = re.search(regex, line)
264  if m and not m.start():
265    return pos + m.end()
266  else:
267    return pos
268
269
270def SkipUntil(lines, pos, regex, token_type):
271  line = lines[pos.line][pos.column:]
272  m = re.search(regex, line)
273  if m:
274    return pos + m.start()
275  else:
276    print ('ERROR: %s expected on line %s after column %s.' %
277           (token_type, pos.line + 1, pos.column))
278    sys.exit(1)
279
280
281def ParseExpTokenInParens(lines, pos):
282  def ParseInParens(pos):
283    pos = Skip(lines, pos, OPTIONAL_WHITE_SPACES_REGEX)
284    pos = Skip(lines, pos, r'\(')
285    pos = Parse(pos)
286    pos = Skip(lines, pos, r'\)')
287    return pos
288
289  def Parse(pos):
290    pos = SkipUntil(lines, pos, r'\(|\)', ')')
291    if SubString(lines, pos, pos + 1) == '(':
292      pos = Parse(pos + 1)
293      pos = Skip(lines, pos, r'\)')
294      return Parse(pos)
295    else:
296      return pos
297
298  start = pos.Clone()
299  pos = ParseInParens(pos)
300  return MakeToken(lines, start, pos, 'exp')
301
302
303def RStripNewLineFromToken(token):
304  if token.value.endswith('\n'):
305    return Token(token.start, token.end, token.value[:-1], token.token_type)
306  else:
307    return token
308
309
310def TokenizeLines(lines, pos):
311  while True:
312    found = FindFirst(lines, TOKEN_TABLE, pos)
313    if not found:
314      yield MakeToken(lines, pos, Eof(), 'code')
315      return
316
317    if found.start == pos:
318      prev_token = None
319      prev_token_rstripped = None
320    else:
321      prev_token = MakeToken(lines, pos, found.start, 'code')
322      prev_token_rstripped = RStripNewLineFromToken(prev_token)
323
324    if found.token_type == '$var':
325      if prev_token_rstripped:
326        yield prev_token_rstripped
327      yield found
328      id_token = ParseToken(lines, found.end, ID_REGEX, 'id')
329      yield id_token
330      pos = Skip(lines, id_token.end, OPTIONAL_WHITE_SPACES_REGEX)
331
332      eq_token = ParseToken(lines, pos, EQ_REGEX, '=')
333      yield eq_token
334      pos = Skip(lines, eq_token.end, r'\s*')
335
336      if SubString(lines, pos, pos + 2) != '[[':
337        exp_token = ParseToken(lines, pos, REST_OF_LINE_REGEX, 'exp')
338        yield exp_token
339        pos = Cursor(exp_token.end.line + 1, 0)
340    elif found.token_type == '$for':
341      if prev_token_rstripped:
342        yield prev_token_rstripped
343      yield found
344      id_token = ParseToken(lines, found.end, ID_REGEX, 'id')
345      yield id_token
346      pos = Skip(lines, id_token.end, WHITE_SPACE_REGEX)
347    elif found.token_type == '$range':
348      if prev_token_rstripped:
349        yield prev_token_rstripped
350      yield found
351      id_token = ParseToken(lines, found.end, ID_REGEX, 'id')
352      yield id_token
353      pos = Skip(lines, id_token.end, OPTIONAL_WHITE_SPACES_REGEX)
354
355      dots_pos = SkipUntil(lines, pos, DOT_DOT_REGEX, '..')
356      yield MakeToken(lines, pos, dots_pos, 'exp')
357      yield MakeToken(lines, dots_pos, dots_pos + 2, '..')
358      pos = dots_pos + 2
359      new_pos = Cursor(pos.line + 1, 0)
360      yield MakeToken(lines, pos, new_pos, 'exp')
361      pos = new_pos
362    elif found.token_type == '$':
363      if prev_token:
364        yield prev_token
365      yield found
366      exp_token = ParseExpTokenInParens(lines, found.end)
367      yield exp_token
368      pos = exp_token.end
369    elif (found.token_type == ']]' or found.token_type == '$if' or
370          found.token_type == '$elif' or found.token_type == '$else'):
371      if prev_token_rstripped:
372        yield prev_token_rstripped
373      yield found
374      pos = found.end
375    else:
376      if prev_token:
377        yield prev_token
378      yield found
379      pos = found.end
380
381
382def Tokenize(s):
383  """A generator that yields the tokens in the given string."""
384  if s != '':
385    lines = s.splitlines(True)
386    for token in TokenizeLines(lines, Cursor(0, 0)):
387      yield token
388
389
390class CodeNode:
391  def __init__(self, atomic_code_list=None):
392    self.atomic_code = atomic_code_list
393
394
395class VarNode:
396  def __init__(self, identifier=None, atomic_code=None):
397    self.identifier = identifier
398    self.atomic_code = atomic_code
399
400
401class RangeNode:
402  def __init__(self, identifier=None, exp1=None, exp2=None):
403    self.identifier = identifier
404    self.exp1 = exp1
405    self.exp2 = exp2
406
407
408class ForNode:
409  def __init__(self, identifier=None, sep=None, code=None):
410    self.identifier = identifier
411    self.sep = sep
412    self.code = code
413
414
415class ElseNode:
416  def __init__(self, else_branch=None):
417    self.else_branch = else_branch
418
419
420class IfNode:
421  def __init__(self, exp=None, then_branch=None, else_branch=None):
422    self.exp = exp
423    self.then_branch = then_branch
424    self.else_branch = else_branch
425
426
427class RawCodeNode:
428  def __init__(self, token=None):
429    self.raw_code = token
430
431
432class LiteralDollarNode:
433  def __init__(self, token):
434    self.token = token
435
436
437class ExpNode:
438  def __init__(self, token, python_exp):
439    self.token = token
440    self.python_exp = python_exp
441
442
443def PopFront(a_list):
444  head = a_list[0]
445  a_list[:1] = []
446  return head
447
448
449def PushFront(a_list, elem):
450  a_list[:0] = [elem]
451
452
453def PopToken(a_list, token_type=None):
454  token = PopFront(a_list)
455  if token_type is not None and token.token_type != token_type:
456    print 'ERROR: %s expected at %s' % (token_type, token.start)
457    print 'ERROR: %s found instead' % (token,)
458    sys.exit(1)
459
460  return token
461
462
463def PeekToken(a_list):
464  if not a_list:
465    return None
466
467  return a_list[0]
468
469
470def ParseExpNode(token):
471  python_exp = re.sub(r'([_A-Za-z]\w*)', r'self.GetValue("\1")', token.value)
472  return ExpNode(token, python_exp)
473
474
475def ParseElseNode(tokens):
476  def Pop(token_type=None):
477    return PopToken(tokens, token_type)
478
479  next = PeekToken(tokens)
480  if not next:
481    return None
482  if next.token_type == '$else':
483    Pop('$else')
484    Pop('[[')
485    code_node = ParseCodeNode(tokens)
486    Pop(']]')
487    return code_node
488  elif next.token_type == '$elif':
489    Pop('$elif')
490    exp = Pop('code')
491    Pop('[[')
492    code_node = ParseCodeNode(tokens)
493    Pop(']]')
494    inner_else_node = ParseElseNode(tokens)
495    return CodeNode([IfNode(ParseExpNode(exp), code_node, inner_else_node)])
496  elif not next.value.strip():
497    Pop('code')
498    return ParseElseNode(tokens)
499  else:
500    return None
501
502
503def ParseAtomicCodeNode(tokens):
504  def Pop(token_type=None):
505    return PopToken(tokens, token_type)
506
507  head = PopFront(tokens)
508  t = head.token_type
509  if t == 'code':
510    return RawCodeNode(head)
511  elif t == '$var':
512    id_token = Pop('id')
513    Pop('=')
514    next = PeekToken(tokens)
515    if next.token_type == 'exp':
516      exp_token = Pop()
517      return VarNode(id_token, ParseExpNode(exp_token))
518    Pop('[[')
519    code_node = ParseCodeNode(tokens)
520    Pop(']]')
521    return VarNode(id_token, code_node)
522  elif t == '$for':
523    id_token = Pop('id')
524    next_token = PeekToken(tokens)
525    if next_token.token_type == 'code':
526      sep_token = next_token
527      Pop('code')
528    else:
529      sep_token = None
530    Pop('[[')
531    code_node = ParseCodeNode(tokens)
532    Pop(']]')
533    return ForNode(id_token, sep_token, code_node)
534  elif t == '$if':
535    exp_token = Pop('code')
536    Pop('[[')
537    code_node = ParseCodeNode(tokens)
538    Pop(']]')
539    else_node = ParseElseNode(tokens)
540    return IfNode(ParseExpNode(exp_token), code_node, else_node)
541  elif t == '$range':
542    id_token = Pop('id')
543    exp1_token = Pop('exp')
544    Pop('..')
545    exp2_token = Pop('exp')
546    return RangeNode(id_token, ParseExpNode(exp1_token),
547                     ParseExpNode(exp2_token))
548  elif t == '$id':
549    return ParseExpNode(Token(head.start + 1, head.end, head.value[1:], 'id'))
550  elif t == '$($)':
551    return LiteralDollarNode(head)
552  elif t == '$':
553    exp_token = Pop('exp')
554    return ParseExpNode(exp_token)
555  elif t == '[[':
556    code_node = ParseCodeNode(tokens)
557    Pop(']]')
558    return code_node
559  else:
560    PushFront(tokens, head)
561    return None
562
563
564def ParseCodeNode(tokens):
565  atomic_code_list = []
566  while True:
567    if not tokens:
568      break
569    atomic_code_node = ParseAtomicCodeNode(tokens)
570    if atomic_code_node:
571      atomic_code_list.append(atomic_code_node)
572    else:
573      break
574  return CodeNode(atomic_code_list)
575
576
577def ParseToAST(pump_src_text):
578  """Convert the given Pump source text into an AST."""
579  tokens = list(Tokenize(pump_src_text))
580  code_node = ParseCodeNode(tokens)
581  return code_node
582
583
584class Env:
585  def __init__(self):
586    self.variables = []
587    self.ranges = []
588
589  def Clone(self):
590    clone = Env()
591    clone.variables = self.variables[:]
592    clone.ranges = self.ranges[:]
593    return clone
594
595  def PushVariable(self, var, value):
596    # If value looks like an int, store it as an int.
597    try:
598      int_value = int(value)
599      if ('%s' % int_value) == value:
600        value = int_value
601    except Exception:
602      pass
603    self.variables[:0] = [(var, value)]
604
605  def PopVariable(self):
606    self.variables[:1] = []
607
608  def PushRange(self, var, lower, upper):
609    self.ranges[:0] = [(var, lower, upper)]
610
611  def PopRange(self):
612    self.ranges[:1] = []
613
614  def GetValue(self, identifier):
615    for (var, value) in self.variables:
616      if identifier == var:
617        return value
618
619    print 'ERROR: meta variable %s is undefined.' % (identifier,)
620    sys.exit(1)
621
622  def EvalExp(self, exp):
623    try:
624      result = eval(exp.python_exp)
625    except Exception, e:
626      print 'ERROR: caught exception %s: %s' % (e.__class__.__name__, e)
627      print ('ERROR: failed to evaluate meta expression %s at %s' %
628             (exp.python_exp, exp.token.start))
629      sys.exit(1)
630    return result
631
632  def GetRange(self, identifier):
633    for (var, lower, upper) in self.ranges:
634      if identifier == var:
635        return (lower, upper)
636
637    print 'ERROR: range %s is undefined.' % (identifier,)
638    sys.exit(1)
639
640
641class Output:
642  def __init__(self):
643    self.string = ''
644
645  def GetLastLine(self):
646    index = self.string.rfind('\n')
647    if index < 0:
648      return ''
649
650    return self.string[index + 1:]
651
652  def Append(self, s):
653    self.string += s
654
655
656def RunAtomicCode(env, node, output):
657  if isinstance(node, VarNode):
658    identifier = node.identifier.value.strip()
659    result = Output()
660    RunAtomicCode(env.Clone(), node.atomic_code, result)
661    value = result.string
662    env.PushVariable(identifier, value)
663  elif isinstance(node, RangeNode):
664    identifier = node.identifier.value.strip()
665    lower = int(env.EvalExp(node.exp1))
666    upper = int(env.EvalExp(node.exp2))
667    env.PushRange(identifier, lower, upper)
668  elif isinstance(node, ForNode):
669    identifier = node.identifier.value.strip()
670    if node.sep is None:
671      sep = ''
672    else:
673      sep = node.sep.value
674    (lower, upper) = env.GetRange(identifier)
675    for i in range(lower, upper + 1):
676      new_env = env.Clone()
677      new_env.PushVariable(identifier, i)
678      RunCode(new_env, node.code, output)
679      if i != upper:
680        output.Append(sep)
681  elif isinstance(node, RawCodeNode):
682    output.Append(node.raw_code.value)
683  elif isinstance(node, IfNode):
684    cond = env.EvalExp(node.exp)
685    if cond:
686      RunCode(env.Clone(), node.then_branch, output)
687    elif node.else_branch is not None:
688      RunCode(env.Clone(), node.else_branch, output)
689  elif isinstance(node, ExpNode):
690    value = env.EvalExp(node)
691    output.Append('%s' % (value,))
692  elif isinstance(node, LiteralDollarNode):
693    output.Append('$')
694  elif isinstance(node, CodeNode):
695    RunCode(env.Clone(), node, output)
696  else:
697    print 'BAD'
698    print node
699    sys.exit(1)
700
701
702def RunCode(env, code_node, output):
703  for atomic_code in code_node.atomic_code:
704    RunAtomicCode(env, atomic_code, output)
705
706
707def IsComment(cur_line):
708  return '//' in cur_line
709
710
711def IsInPreprocessorDirevative(prev_lines, cur_line):
712  if cur_line.lstrip().startswith('#'):
713    return True
714  return prev_lines != [] and prev_lines[-1].endswith('\\')
715
716
717def WrapComment(line, output):
718  loc = line.find('//')
719  before_comment = line[:loc].rstrip()
720  if before_comment == '':
721    indent = loc
722  else:
723    output.append(before_comment)
724    indent = len(before_comment) - len(before_comment.lstrip())
725  prefix = indent*' ' + '// '
726  max_len = 80 - len(prefix)
727  comment = line[loc + 2:].strip()
728  segs = [seg for seg in re.split(r'(\w+\W*)', comment) if seg != '']
729  cur_line = ''
730  for seg in segs:
731    if len((cur_line + seg).rstrip()) < max_len:
732      cur_line += seg
733    else:
734      if cur_line.strip() != '':
735        output.append(prefix + cur_line.rstrip())
736      cur_line = seg.lstrip()
737  if cur_line.strip() != '':
738    output.append(prefix + cur_line.strip())
739
740
741def WrapCode(line, line_concat, output):
742  indent = len(line) - len(line.lstrip())
743  prefix = indent*' '  # Prefix of the current line
744  max_len = 80 - indent - len(line_concat)  # Maximum length of the current line
745  new_prefix = prefix + 4*' '  # Prefix of a continuation line
746  new_max_len = max_len - 4  # Maximum length of a continuation line
747  # Prefers to wrap a line after a ',' or ';'.
748  segs = [seg for seg in re.split(r'([^,;]+[,;]?)', line.strip()) if seg != '']
749  cur_line = ''  # The current line without leading spaces.
750  for seg in segs:
751    # If the line is still too long, wrap at a space.
752    while cur_line == '' and len(seg.strip()) > max_len:
753      seg = seg.lstrip()
754      split_at = seg.rfind(' ', 0, max_len)
755      output.append(prefix + seg[:split_at].strip() + line_concat)
756      seg = seg[split_at + 1:]
757      prefix = new_prefix
758      max_len = new_max_len
759
760    if len((cur_line + seg).rstrip()) < max_len:
761      cur_line = (cur_line + seg).lstrip()
762    else:
763      output.append(prefix + cur_line.rstrip() + line_concat)
764      prefix = new_prefix
765      max_len = new_max_len
766      cur_line = seg.lstrip()
767  if cur_line.strip() != '':
768    output.append(prefix + cur_line.strip())
769
770
771def WrapPreprocessorDirevative(line, output):
772  WrapCode(line, ' \\', output)
773
774
775def WrapPlainCode(line, output):
776  WrapCode(line, '', output)
777
778
779def IsHeaderGuardOrInclude(line):
780  return (re.match(r'^#(ifndef|define|endif\s*//)\s*[\w_]+\s*$', line) or
781          re.match(r'^#include\s', line))
782
783
784def WrapLongLine(line, output):
785  line = line.rstrip()
786  if len(line) <= 80:
787    output.append(line)
788  elif IsComment(line):
789    if IsHeaderGuardOrInclude(line):
790      # The style guide made an exception to allow long header guard lines
791      # and includes.
792      output.append(line)
793    else:
794      WrapComment(line, output)
795  elif IsInPreprocessorDirevative(output, line):
796    if IsHeaderGuardOrInclude(line):
797      # The style guide made an exception to allow long header guard lines
798      # and includes.
799      output.append(line)
800    else:
801      WrapPreprocessorDirevative(line, output)
802  else:
803    WrapPlainCode(line, output)
804
805
806def BeautifyCode(string):
807  lines = string.splitlines()
808  output = []
809  for line in lines:
810    WrapLongLine(line, output)
811  output2 = [line.rstrip() for line in output]
812  return '\n'.join(output2) + '\n'
813
814
815def ConvertFromPumpSource(src_text):
816  """Return the text generated from the given Pump source text."""
817  ast = ParseToAST(StripMetaComments(src_text))
818  output = Output()
819  RunCode(Env(), ast, output)
820  return BeautifyCode(output.string)
821
822
823def main(argv):
824  if len(argv) == 1:
825    print __doc__
826    sys.exit(1)
827
828  file_path = argv[-1]
829  output_str = ConvertFromPumpSource(file(file_path, 'r').read())
830  if file_path.endswith('.pump'):
831    output_file_path = file_path[:-5]
832  else:
833    output_file_path = '-'
834  if output_file_path == '-':
835    print output_str,
836  else:
837    output_file = file(output_file_path, 'w')
838    output_file.write('// This file was GENERATED by command:\n')
839    output_file.write('//     %s %s\n' %
840                      (os.path.basename(__file__), os.path.basename(file_path)))
841    output_file.write('// DO NOT EDIT BY HAND!!!\n\n')
842    output_file.write(output_str)
843    output_file.close()
844
845
846if __name__ == '__main__':
847  main(sys.argv)
848