stgit/stack.py

   1 """Basic quilt-like functionality
   2 """
   3
   4 __copyright__ = """
   5 Copyright (C) 2005, Catalin Marinas <catalin.marinas@gmail.com>
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License version 2 as
   9 published by the Free Software Foundation.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19 """
  20
  21 import sys, os
  22
  23 from stgit.utils import *
  24 from stgit import git
  25 from stgit.config import config
  26
  27
  28 # stack exception class
  29 class StackException(Exception):
  30     pass
  31
  32 class FilterUntil:
  33     def __init__(self):
  34         self.should_print = True
  35     def __call__(self, x, until_test, prefix):
  36         if until_test(x):
  37             self.should_print = False
  38         if self.should_print:
  39             return x[0:len(prefix)] != prefix
  40         return False
  41
  42 #
  43 # Functions
  44 #
  45 __comment_prefix = 'STG:'
  46 __patch_prefix = 'STG_PATCH:'
  47
  48 def __clean_comments(f):
  49     """Removes lines marked for status in a commit file
  50     """
  51     f.seek(0)
  52
  53     # remove status-prefixed lines
  54     lines = f.readlines()
  55
  56     patch_filter = FilterUntil()
  57     until_test = lambda t: t == (__patch_prefix + '\n')
  58     lines = [l for l in lines if patch_filter(l, until_test, __comment_prefix)]
  59
  60     # remove empty lines at the end
  61     while len(lines) != 0 and lines[-1] == '\n':
  62         del lines[-1]
  63
  64     f.seek(0); f.truncate()
  65     f.writelines(lines)
  66
  67 def edit_file(series, line, comment, show_patch = True):
  68     fname = '.stgit.msg'
  69     tmpl = os.path.join(git.base_dir, 'patchdescr.tmpl')
  70
  71     f = file(fname, 'w+')
  72     if line:
  73         print >> f, line
  74     elif os.path.isfile(tmpl):
  75         print >> f, file(tmpl).read().rstrip()
  76     else:
  77         print >> f
  78     print >> f, __comment_prefix, comment
  79     print >> f, __comment_prefix, \
  80           'Lines prefixed with "%s" will be automatically removed.' \
  81           % __comment_prefix
  82     print >> f, __comment_prefix, \
  83           'Trailing empty lines will be automatically removed.'
  84
  85     if show_patch:
  86        print >> f, __patch_prefix
  87        # series.get_patch(series.get_current()).get_top()
  88        git.diff([], series.get_patch(series.get_current()).get_bottom(), None, f)
  89
  90     #Vim modeline must be near the end.
  91     print >> f, __comment_prefix, 'vi: set textwidth=75 filetype=diff nobackup:'
  92     f.close()
  93
  94     # the editor
  95     if config.has_option('stgit', 'editor'):
  96         editor = config.get('stgit', 'editor')
  97     elif 'EDITOR' in os.environ:
  98         editor = os.environ['EDITOR']
  99     else:
 100         editor = 'vi'
 101     editor += ' %s' % fname
 102
 103     print 'Invoking the editor: "%s"...' % editor,
 104     sys.stdout.flush()
 105     print 'done (exit code: %d)' % os.system(editor)
 106
 107     f = file(fname, 'r+')
 108
 109     __clean_comments(f)
 110     f.seek(0)
 111     result = f.read()
 112
 113     f.close()
 114     os.remove(fname)
 115
 116     return result
 117
 118 #
 119 # Classes
 120 #
 121
 122 class Patch:
 123     """Basic patch implementation
 124     """
 125     def __init__(self, name, patch_dir):
 126         self.__patch_dir = patch_dir
 127         self.__name = name
 128         self.__dir = os.path.join(self.__patch_dir, self.__name)
 129
 130     def create(self):
 131         os.mkdir(self.__dir)
 132         create_empty_file(os.path.join(self.__dir, 'bottom'))
 133         create_empty_file(os.path.join(self.__dir, 'top'))
 134
 135     def delete(self):
 136         for f in os.listdir(self.__dir):
 137             os.remove(os.path.join(self.__dir, f))
 138         os.rmdir(self.__dir)
 139
 140     def get_name(self):
 141         return self.__name
 142
 143     def rename(self, newname):
 144         olddir = self.__dir
 145         self.__name = newname
 146         self.__dir = os.path.join(self.__patch_dir, self.__name)
 147
 148         os.rename(olddir, self.__dir)
 149
 150     def __get_field(self, name, multiline = False):
 151         id_file = os.path.join(self.__dir, name)
 152         if os.path.isfile(id_file):
 153             line = read_string(id_file, multiline)
 154             if line == '':
 155                 return None
 156             else:
 157                 return line
 158         else:
 159             return None
 160
 161     def __set_field(self, name, value, multiline = False):
 162         fname = os.path.join(self.__dir, name)
 163         if value and value != '':
 164             write_string(fname, value, multiline)
 165         elif os.path.isfile(fname):
 166             os.remove(fname)
 167
 168     def get_old_bottom(self):
 169         return self.__get_field('bottom.old')
 170
 171     def get_bottom(self):
 172         return self.__get_field('bottom')
 173
 174     def set_bottom(self, value, backup = False):
 175         if backup:
 176             curr = self.__get_field('bottom')
 177             if curr != value:
 178                 self.__set_field('bottom.old', curr)
 179             else:
 180                 self.__set_field('bottom.old', None)
 181         self.__set_field('bottom', value)
 182
 183     def get_old_top(self):
 184         return self.__get_field('top.old')
 185
 186     def get_top(self):
 187         return self.__get_field('top')
 188
 189     def set_top(self, value, backup = False):
 190         if backup:
 191             curr = self.__get_field('top')
 192             if curr != value:
 193                 self.__set_field('top.old', curr)
 194             else:
 195                 self.__set_field('top.old', None)
 196         self.__set_field('top', value)
 197
 198     def restore_old_boundaries(self):
 199         bottom = self.__get_field('bottom.old')
 200         top = self.__get_field('top.old')
 201
 202         if top and bottom:
 203             self.__set_field('bottom', bottom)
 204             self.__set_field('top', top)
 205             return True
 206         else:
 207             return False
 208
 209     def get_description(self):
 210         return self.__get_field('description', True)
 211
 212     def set_description(self, line):
 213         self.__set_field('description', line, True)
 214
 215     def get_authname(self):
 216         return self.__get_field('authname')
 217
 218     def set_authname(self, name):
 219         if not name and config.has_option('stgit', 'authname'):
 220             name = config.get('stgit', 'authname')
 221         self.__set_field('authname', name)
 222
 223     def get_authemail(self):
 224         return self.__get_field('authemail')
 225
 226     def set_authemail(self, address):
 227         if not address and config.has_option('stgit', 'authemail'):
 228             address = config.get('stgit', 'authemail')
 229         self.__set_field('authemail', address)
 230
 231     def get_authdate(self):
 232         return self.__get_field('authdate')
 233
 234     def set_authdate(self, authdate):
 235         self.__set_field('authdate', authdate)
 236
 237     def get_commname(self):
 238         return self.__get_field('commname')
 239
 240     def set_commname(self, name):
 241         if not name and config.has_option('stgit', 'commname'):
 242             name = config.get('stgit', 'commname')
 243         self.__set_field('commname', name)
 244
 245     def get_commemail(self):
 246         return self.__get_field('commemail')
 247
 248     def set_commemail(self, address):
 249         if not address and config.has_option('stgit', 'commemail'):
 250             address = config.get('stgit', 'commemail')
 251         self.__set_field('commemail', address)
 252
 253
 254 class Series:
 255     """Class including the operations on series
 256     """
 257     def __init__(self, name = None):
 258         """Takes a series name as the parameter.
 259         """
 260         if name:
 261             self.__name = name
 262         else:
 263             self.__name = git.get_head_file()
 264
 265         if self.__name:
 266             self.__patch_dir = os.path.join(git.base_dir, 'patches',
 267                                             self.__name)
 268             self.__base_file = os.path.join(git.base_dir, 'refs', 'bases',
 269                                             self.__name)
 270             self.__applied_file = os.path.join(self.__patch_dir, 'applied')
 271             self.__unapplied_file = os.path.join(self.__patch_dir, 'unapplied')
 272             self.__current_file = os.path.join(self.__patch_dir, 'current')
 273             self.__descr_file = os.path.join(self.__patch_dir, 'description')
 274
 275     def get_branch(self):
 276         """Return the branch name for the Series object
 277         """
 278         return self.__name
 279
 280     def __set_current(self, name):
 281         """Sets the topmost patch
 282         """
 283         if name:
 284             write_string(self.__current_file, name)
 285         else:
 286             create_empty_file(self.__current_file)
 287
 288     def get_patch(self, name):
 289         """Return a Patch object for the given name
 290         """
 291         return Patch(name, self.__patch_dir)
 292
 293     def get_current(self):
 294         """Return a Patch object representing the topmost patch
 295         """
 296         if os.path.isfile(self.__current_file):
 297             name = read_string(self.__current_file)
 298         else:
 299             return None
 300         if name == '':
 301             return None
 302         else:
 303             return name
 304
 305     def get_applied(self):
 306         if not os.path.isfile(self.__applied_file):
 307             raise StackException, 'Branch "%s" not initialised' % self.__name
 308         f = file(self.__applied_file)
 309         names = [line.strip() for line in f.readlines()]
 310         f.close()
 311         return names
 312
 313     def get_unapplied(self):
 314         if not os.path.isfile(self.__unapplied_file):
 315             raise StackException, 'Branch "%s" not initialised' % self.__name
 316         f = file(self.__unapplied_file)
 317         names = [line.strip() for line in f.readlines()]
 318         f.close()
 319         return names
 320
 321     def get_base_file(self):
 322         return self.__base_file
 323
 324     def get_protected(self):
 325         return os.path.isfile(os.path.join(self.__patch_dir, 'protected'))
 326
 327     def protect(self):
 328         protect_file = os.path.join(self.__patch_dir, 'protected')
 329         if not os.path.isfile(protect_file):
 330             create_empty_file(protect_file)
 331
 332     def unprotect(self):
 333         protect_file = os.path.join(self.__patch_dir, 'protected')
 334         if os.path.isfile(protect_file):
 335             os.remove(protect_file)
 336
 337     def get_description(self):
 338         if os.path.isfile(self.__descr_file):
 339             return read_string(self.__descr_file)
 340         else:
 341             return ''
 342
 343     def __patch_is_current(self, patch):
 344         return patch.get_name() == read_string(self.__current_file)
 345
 346     def __patch_applied(self, name):
 347         """Return true if the patch exists in the applied list
 348         """
 349         return name in self.get_applied()
 350
 351     def __patch_unapplied(self, name):
 352         """Return true if the patch exists in the unapplied list
 353         """
 354         return name in self.get_unapplied()
 355
 356     def __begin_stack_check(self):
 357         """Save the current HEAD into .git/refs/heads/base if the stack
 358         is empty
 359         """
 360         if len(self.get_applied()) == 0:
 361             head = git.get_head()
 362             write_string(self.__base_file, head)
 363
 364     def __end_stack_check(self):
 365         """Remove .git/refs/heads/base if the stack is empty.
 366         This warning should never happen
 367         """
 368         if len(self.get_applied()) == 0 \
 369            and read_string(self.__base_file) != git.get_head():
 370             print 'Warning: stack empty but the HEAD and base are different'
 371
 372     def head_top_equal(self):
 373         """Return true if the head and the top are the same
 374         """
 375         crt = self.get_current()
 376         if not crt:
 377             # we don't care, no patches applied
 378             return True
 379         return git.get_head() == Patch(crt, self.__patch_dir).get_top()
 380
 381     def is_initialised(self):
 382         """Checks if series is already initialised
 383         """
 384         return os.path.isdir(self.__patch_dir)
 385
 386     def init(self):
 387         """Initialises the stgit series
 388         """
 389         bases_dir = os.path.join(git.base_dir, 'refs', 'bases')
 390
 391         if self.is_initialised():
 392             raise StackException, self.__patch_dir + ' already exists'
 393         os.makedirs(self.__patch_dir)
 394
 395         if not os.path.isdir(bases_dir):
 396             os.makedirs(bases_dir)
 397
 398         create_empty_file(self.__applied_file)
 399         create_empty_file(self.__unapplied_file)
 400         create_empty_file(self.__descr_file)
 401         self.__begin_stack_check()
 402
 403     def rename(self, to_name):
 404         """Renames a series
 405         """
 406         to_stack = Series(to_name)
 407
 408         if to_stack.is_initialised():
 409             raise StackException, '"%s" already exists' % to_stack.get_branch()
 410         if os.path.exists(to_stack.__base_file):
 411             os.remove(to_stack.__base_file)
 412
 413         git.rename_branch(self.__name, to_name)
 414
 415         if os.path.isdir(self.__patch_dir):
 416             os.rename(self.__patch_dir, to_stack.__patch_dir)
 417         if os.path.exists(self.__base_file):
 418             os.rename(self.__base_file, to_stack.__base_file)
 419
 420         self.__init__(to_name)
 421
 422     def delete(self, force = False):
 423         """Deletes an stgit series
 424         """
 425         if self.is_initialised():
 426             patches = self.get_unapplied() + self.get_applied()
 427             if not force and patches:
 428                 raise StackException, \
 429                       'Cannot delete: the series still contains patches'
 430             patches.reverse()
 431             for p in patches:
 432                 self.delete_patch(p)
 433
 434             if os.path.exists(self.__applied_file):
 435                 os.remove(self.__applied_file)
 436             if os.path.exists(self.__unapplied_file):
 437                 os.remove(self.__unapplied_file)
 438             if os.path.exists(self.__current_file):
 439                 os.remove(self.__current_file)
 440             if os.path.exists(self.__descr_file):
 441                 os.remove(self.__descr_file)
 442             if not os.listdir(self.__patch_dir):
 443                 os.rmdir(self.__patch_dir)
 444             else:
 445                 print 'Series directory %s is not empty.' % self.__name
 446
 447         if os.path.exists(self.__base_file):
 448             os.remove(self.__base_file)
 449
 450     def refresh_patch(self, message = None, edit = False, show_patch = False,
 451                       cache_update = True,
 452                       author_name = None, author_email = None,
 453                       author_date = None,
 454                       committer_name = None, committer_email = None):
 455         """Generates a new commit for the given patch
 456         """
 457         name = self.get_current()
 458         if not name:
 459             raise StackException, 'No patches applied'
 460
 461         patch = Patch(name, self.__patch_dir)
 462
 463         descr = patch.get_description()
 464         if not (message or descr):
 465             edit = True
 466             descr = ''
 467         elif message:
 468             descr = message
 469
 470         if not message and edit:
 471             descr = edit_file(self, descr.rstrip(), \
 472                               'Please edit the description for patch "%s" ' \
 473                               'above.' % name, show_patch)
 474
 475         if not author_name:
 476             author_name = patch.get_authname()
 477         if not author_email:
 478             author_email = patch.get_authemail()
 479         if not author_date:
 480             author_date = patch.get_authdate()
 481         if not committer_name:
 482             committer_name = patch.get_commname()
 483         if not committer_email:
 484             committer_email = patch.get_commemail()
 485
 486         commit_id = git.commit(message = descr, parents = [patch.get_bottom()],
 487                                cache_update = cache_update,
 488                                allowempty = True,
 489                                author_name = author_name,
 490                                author_email = author_email,
 491                                author_date = author_date,
 492                                committer_name = committer_name,
 493                                committer_email = committer_email)
 494
 495         patch.set_top(commit_id)
 496         patch.set_description(descr)
 497         patch.set_authname(author_name)
 498         patch.set_authemail(author_email)
 499         patch.set_authdate(author_date)
 500         patch.set_commname(committer_name)
 501         patch.set_commemail(committer_email)
 502
 503         return commit_id
 504
 505     def new_patch(self, name, message = None, can_edit = True,
 506                   unapplied = False, show_patch = False,
 507                   top = None, bottom = None,
 508                   author_name = None, author_email = None, author_date = None,
 509                   committer_name = None, committer_email = None):
 510         """Creates a new patch
 511         """
 512         if self.__patch_applied(name) or self.__patch_unapplied(name):
 513             raise StackException, 'Patch "%s" already exists' % name
 514
 515         if not message and can_edit:
 516             descr = edit_file(self, None, \
 517                               'Please enter the description for patch "%s" ' \
 518                               'above.' % name, show_patch)
 519         else:
 520             descr = message
 521
 522         head = git.get_head()
 523
 524         self.__begin_stack_check()
 525
 526         patch = Patch(name, self.__patch_dir)
 527         patch.create()
 528
 529         if bottom:
 530             patch.set_bottom(bottom)
 531         else:
 532             patch.set_bottom(head)
 533         if top:
 534             patch.set_top(top)
 535         else:
 536             patch.set_top(head)
 537
 538         patch.set_description(descr)
 539         patch.set_authname(author_name)
 540         patch.set_authemail(author_email)
 541         patch.set_authdate(author_date)
 542         patch.set_commname(committer_name)
 543         patch.set_commemail(committer_email)
 544
 545         if unapplied:
 546             patches = [patch.get_name()] + self.get_unapplied()
 547
 548             f = file(self.__unapplied_file, 'w+')
 549             f.writelines([line + '\n' for line in patches])
 550             f.close()
 551         else:
 552             append_string(self.__applied_file, patch.get_name())
 553             self.__set_current(name)
 554
 555     def delete_patch(self, name):
 556         """Deletes a patch
 557         """
 558         patch = Patch(name, self.__patch_dir)
 559
 560         if self.__patch_is_current(patch):
 561             self.pop_patch(name)
 562         elif self.__patch_applied(name):
 563             raise StackException, 'Cannot remove an applied patch, "%s", ' \
 564                   'which is not current' % name
 565         elif not name in self.get_unapplied():
 566             raise StackException, 'Unknown patch "%s"' % name
 567
 568         patch.delete()
 569
 570         unapplied = self.get_unapplied()
 571         unapplied.remove(name)
 572         f = file(self.__unapplied_file, 'w+')
 573         f.writelines([line + '\n' for line in unapplied])
 574         f.close()
 575
 576     def forward_patches(self, names):
 577         """Try to fast-forward an array of patches.
 578
 579         On return, patches in names[0:returned_value] have been pushed on the
 580         stack. Apply the rest with push_patch
 581         """
 582         unapplied = self.get_unapplied()
 583         self.__begin_stack_check()
 584
 585         forwarded = 0
 586         top = git.get_head()
 587
 588         for name in names:
 589             assert(name in unapplied)
 590
 591             patch = Patch(name, self.__patch_dir)
 592
 593             head = top
 594             bottom = patch.get_bottom()
 595             top = patch.get_top()
 596
 597             # top != bottom always since we have a commit for each patch
 598             if head == bottom:
 599                 # reset the backup information
 600                 patch.set_bottom(head, backup = True)
 601                 patch.set_top(top, backup = True)
 602
 603             else:
 604                 head_tree = git.get_commit(head).get_tree()
 605                 bottom_tree = git.get_commit(bottom).get_tree()
 606                 if head_tree == bottom_tree:
 607                     # We must just reparent this patch and create a new commit
 608                     # for it
 609                     descr = patch.get_description()
 610                     author_name = patch.get_authname()
 611                     author_email = patch.get_authemail()
 612                     author_date = patch.get_authdate()
 613                     committer_name = patch.get_commname()
 614                     committer_email = patch.get_commemail()
 615
 616                     top_tree = git.get_commit(top).get_tree()
 617
 618                     top = git.commit(message = descr, parents = [head],
 619                                      cache_update = False,
 620                                      tree_id = top_tree,
 621                                      allowempty = True,
 622                                      author_name = author_name,
 623                                      author_email = author_email,
 624                                      author_date = author_date,
 625                                      committer_name = committer_name,
 626                                      committer_email = committer_email)
 627
 628                     patch.set_bottom(head, backup = True)
 629                     patch.set_top(top, backup = True)
 630                 else:
 631                     top = head
 632                     # stop the fast-forwarding, must do a real merge
 633                     break
 634
 635             forwarded+=1
 636             unapplied.remove(name)
 637
 638         git.switch(top)
 639
 640         append_strings(self.__applied_file, names[0:forwarded])
 641
 642         f = file(self.__unapplied_file, 'w+')
 643         f.writelines([line + '\n' for line in unapplied])
 644         f.close()
 645
 646         self.__set_current(name)
 647
 648         return forwarded
 649
 650     def push_patch(self, name):
 651         """Pushes a patch on the stack
 652         """
 653         unapplied = self.get_unapplied()
 654         assert(name in unapplied)
 655
 656         self.__begin_stack_check()
 657
 658         patch = Patch(name, self.__patch_dir)
 659
 660         head = git.get_head()
 661         bottom = patch.get_bottom()
 662         top = patch.get_top()
 663
 664         ex = None
 665         modified = False
 666
 667         # top != bottom always since we have a commit for each patch
 668         if head == bottom:
 669             # reset the backup information
 670             patch.set_bottom(bottom, backup = True)
 671             patch.set_top(top, backup = True)
 672
 673             git.switch(top)
 674         else:
 675             # new patch needs to be refreshed.
 676             # The current patch is empty after merge.
 677             patch.set_bottom(head, backup = True)
 678             patch.set_top(head, backup = True)
 679
 680             # Try the fast applying first. If this fails, fall back to the
 681             # three-way merge
 682             if not git.apply_diff(bottom, top):
 683                 # if git.apply_diff() fails, the patch requires a diff3
 684                 # merge and can be reported as modified
 685                 modified = True
 686
 687                 # merge can fail but the patch needs to be pushed
 688                 try:
 689                     git.merge(bottom, head, top)
 690                 except git.GitException, ex:
 691                     print >> sys.stderr, \
 692                           'The merge failed during "push". ' \
 693                           'Use "refresh" after fixing the conflicts'
 694
 695         append_string(self.__applied_file, name)
 696
 697         unapplied.remove(name)
 698         f = file(self.__unapplied_file, 'w+')
 699         f.writelines([line + '\n' for line in unapplied])
 700         f.close()
 701
 702         self.__set_current(name)
 703
 704         # head == bottom case doesn't need to refresh the patch
 705         if head != bottom:
 706             if not ex:
 707                 # if the merge was OK and no conflicts, just refresh the patch
 708                 # The GIT cache was already updated by the merge operation
 709                 self.refresh_patch(cache_update = False)
 710             else:
 711                 raise StackException, str(ex)
 712
 713         return modified
 714
 715     def undo_push(self):
 716         name = self.get_current()
 717         assert(name)
 718
 719         patch = Patch(name, self.__patch_dir)
 720         git.reset()
 721         self.pop_patch(name)
 722         return patch.restore_old_boundaries()
 723
 724     def pop_patch(self, name):
 725         """Pops the top patch from the stack
 726         """
 727         applied = self.get_applied()
 728         applied.reverse()
 729         assert(name in applied)
 730
 731         patch = Patch(name, self.__patch_dir)
 732
 733         git.switch(patch.get_bottom())
 734
 735         # save the new applied list
 736         idx = applied.index(name) + 1
 737
 738         popped = applied[:idx]
 739         popped.reverse()
 740         unapplied = popped + self.get_unapplied()
 741
 742         f = file(self.__unapplied_file, 'w+')
 743         f.writelines([line + '\n' for line in unapplied])
 744         f.close()
 745
 746         del applied[:idx]
 747         applied.reverse()
 748
 749         f = file(self.__applied_file, 'w+')
 750         f.writelines([line + '\n' for line in applied])
 751         f.close()
 752
 753         if applied == []:
 754             self.__set_current(None)
 755         else:
 756             self.__set_current(applied[-1])
 757
 758         self.__end_stack_check()
 759
 760     def empty_patch(self, name):
 761         """Returns True if the patch is empty
 762         """
 763         patch = Patch(name, self.__patch_dir)
 764         bottom = patch.get_bottom()
 765         top = patch.get_top()
 766
 767         if bottom == top:
 768             return True
 769         elif git.get_commit(top).get_tree() \
 770                  == git.get_commit(bottom).get_tree():
 771             return True
 772
 773         return False
 774
 775     def rename_patch(self, oldname, newname):
 776         applied = self.get_applied()
 777         unapplied = self.get_unapplied()
 778
 779         if oldname == newname:
 780             raise StackException, '"To" name and "from" name are the same'
 781
 782         if newname in applied or newname in unapplied:
 783             raise StackException, 'Patch "%s" already exists' % newname
 784
 785         if oldname in unapplied:
 786             Patch(oldname, self.__patch_dir).rename(newname)
 787             unapplied[unapplied.index(oldname)] = newname
 788
 789             f = file(self.__unapplied_file, 'w+')
 790             f.writelines([line + '\n' for line in unapplied])
 791             f.close()
 792         elif oldname in applied:
 793             Patch(oldname, self.__patch_dir).rename(newname)
 794             if oldname == self.get_current():
 795                 self.__set_current(newname)
 796
 797             applied[applied.index(oldname)] = newname
 798
 799             f = file(self.__applied_file, 'w+')
 800             f.writelines([line + '\n' for line in applied])
 801             f.close()
 802         else:
 803             raise StackException, 'Unknown patch "%s"' % oldname