mdw@git.distorted.org.uk Git - stgit/blob - 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, basedir
  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(basedir.get(), '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, series_dir, refs_dir):
 126         self.__series_dir = series_dir
 127         self.__name = name
 128         self.__dir = os.path.join(self.__series_dir, self.__name)
 129         self.__refs_dir = refs_dir
 130         self.__top_ref_file = os.path.join(self.__refs_dir, self.__name)
 131
 132     def create(self):
 133         os.mkdir(self.__dir)
 134         create_empty_file(os.path.join(self.__dir, 'bottom'))
 135         create_empty_file(os.path.join(self.__dir, 'top'))
 136
 137     def delete(self):
 138         for f in os.listdir(self.__dir):
 139             os.remove(os.path.join(self.__dir, f))
 140         os.rmdir(self.__dir)
 141         os.remove(self.__top_ref_file)
 142
 143     def get_name(self):
 144         return self.__name
 145
 146     def rename(self, newname):
 147         olddir = self.__dir
 148         old_ref_file = self.__top_ref_file
 149         self.__name = newname
 150         self.__dir = os.path.join(self.__series_dir, self.__name)
 151         self.__top_ref_file = os.path.join(self.__refs_dir, self.__name)
 152
 153         os.rename(olddir, self.__dir)
 154         os.rename(old_ref_file, self.__top_ref_file)
 155
 156     def __update_top_ref(self, ref):
 157         write_string(self.__top_ref_file, ref)
 158
 159     def update_top_ref(self):
 160         top = self.get_top()
 161         if top:
 162             self.__update_top_ref(top)
 163
 164     def __get_field(self, name, multiline = False):
 165         id_file = os.path.join(self.__dir, name)
 166         if os.path.isfile(id_file):
 167             line = read_string(id_file, multiline)
 168             if line == '':
 169                 return None
 170             else:
 171                 return line
 172         else:
 173             return None
 174
 175     def __set_field(self, name, value, multiline = False):
 176         fname = os.path.join(self.__dir, name)
 177         if value and value != '':
 178             write_string(fname, value, multiline)
 179         elif os.path.isfile(fname):
 180             os.remove(fname)
 181
 182     def get_old_bottom(self):
 183         return self.__get_field('bottom.old')
 184
 185     def get_bottom(self):
 186         return self.__get_field('bottom')
 187
 188     def set_bottom(self, value, backup = False):
 189         if backup:
 190             curr = self.__get_field('bottom')
 191             self.__set_field('bottom.old', curr)
 192         self.__set_field('bottom', value)
 193
 194     def get_old_top(self):
 195         return self.__get_field('top.old')
 196
 197     def get_top(self):
 198         return self.__get_field('top')
 199
 200     def set_top(self, value, backup = False):
 201         if backup:
 202             curr = self.__get_field('top')
 203             self.__set_field('top.old', curr)
 204         self.__set_field('top', value)
 205         self.__update_top_ref(value)
 206
 207     def restore_old_boundaries(self):
 208         bottom = self.__get_field('bottom.old')
 209         top = self.__get_field('top.old')
 210
 211         if top and bottom:
 212             self.__set_field('bottom', bottom)
 213             self.__set_field('top', top)
 214             self.__update_top_ref(top)
 215             return True
 216         else:
 217             return False
 218
 219     def get_description(self):
 220         return self.__get_field('description', True)
 221
 222     def set_description(self, line):
 223         self.__set_field('description', line, True)
 224
 225     def get_authname(self):
 226         return self.__get_field('authname')
 227
 228     def set_authname(self, name):
 229         if not name:
 230             if config.has_option('stgit', 'authname'):
 231                 name = config.get('stgit', 'authname')
 232             elif 'GIT_AUTHOR_NAME' in os.environ:
 233                 name = os.environ['GIT_AUTHOR_NAME']
 234         self.__set_field('authname', name)
 235
 236     def get_authemail(self):
 237         return self.__get_field('authemail')
 238
 239     def set_authemail(self, address):
 240         if not address:
 241             if config.has_option('stgit', 'authemail'):
 242                 address = config.get('stgit', 'authemail')
 243             elif 'GIT_AUTHOR_EMAIL' in os.environ:
 244                 address = os.environ['GIT_AUTHOR_EMAIL']
 245         self.__set_field('authemail', address)
 246
 247     def get_authdate(self):
 248         return self.__get_field('authdate')
 249
 250     def set_authdate(self, date):
 251         if not date and 'GIT_AUTHOR_DATE' in os.environ:
 252             date = os.environ['GIT_AUTHOR_DATE']
 253         self.__set_field('authdate', date)
 254
 255     def get_commname(self):
 256         return self.__get_field('commname')
 257
 258     def set_commname(self, name):
 259         if not name:
 260             if config.has_option('stgit', 'commname'):
 261                 name = config.get('stgit', 'commname')
 262             elif 'GIT_COMMITTER_NAME' in os.environ:
 263                 name = os.environ['GIT_COMMITTER_NAME']
 264         self.__set_field('commname', name)
 265
 266     def get_commemail(self):
 267         return self.__get_field('commemail')
 268
 269     def set_commemail(self, address):
 270         if not address:
 271             if config.has_option('stgit', 'commemail'):
 272                 address = config.get('stgit', 'commemail')
 273             elif 'GIT_COMMITTER_EMAIL' in os.environ:
 274                 address = os.environ['GIT_COMMITTER_EMAIL']
 275         self.__set_field('commemail', address)
 276
 277
 278 class Series:
 279     """Class including the operations on series
 280     """
 281     def __init__(self, name = None):
 282         """Takes a series name as the parameter.
 283         """
 284         try:
 285             if name:
 286                 self.__name = name
 287             else:
 288                 self.__name = git.get_head_file()
 289             self.__base_dir = basedir.get()
 290         except git.GitException, ex:
 291             raise StackException, 'GIT tree not initialised: %s' % ex
 292
 293         self.__series_dir = os.path.join(self.__base_dir, 'patches',
 294                                          self.__name)
 295         self.__refs_dir = os.path.join(self.__base_dir, 'refs', 'patches',
 296                                        self.__name)
 297         self.__base_file = os.path.join(self.__base_dir, 'refs', 'bases',
 298                                         self.__name)
 299
 300         self.__applied_file = os.path.join(self.__series_dir, 'applied')
 301         self.__unapplied_file = os.path.join(self.__series_dir, 'unapplied')
 302         self.__current_file = os.path.join(self.__series_dir, 'current')
 303         self.__descr_file = os.path.join(self.__series_dir, 'description')
 304
 305         # where this series keeps its patches
 306         self.__patch_dir = os.path.join(self.__series_dir, 'patches')
 307         if not os.path.isdir(self.__patch_dir):
 308             self.__patch_dir = self.__series_dir
 309
 310         # if no __refs_dir, create and populate it (upgrade old repositories)
 311         if self.is_initialised() and not os.path.isdir(self.__refs_dir):
 312             os.makedirs(self.__refs_dir)
 313             for patch in self.get_applied() + self.get_unapplied():
 314                 self.get_patch(patch).update_top_ref()
 315
 316     def get_branch(self):
 317         """Return the branch name for the Series object
 318         """
 319         return self.__name
 320
 321     def __set_current(self, name):
 322         """Sets the topmost patch
 323         """
 324         if name:
 325             write_string(self.__current_file, name)
 326         else:
 327             create_empty_file(self.__current_file)
 328
 329     def get_patch(self, name):
 330         """Return a Patch object for the given name
 331         """
 332         return Patch(name, self.__patch_dir, self.__refs_dir)
 333
 334     def get_current(self):
 335         """Return a Patch object representing the topmost patch
 336         """
 337         if os.path.isfile(self.__current_file):
 338             name = read_string(self.__current_file)
 339         else:
 340             return None
 341         if name == '':
 342             return None
 343         else:
 344             return name
 345
 346     def get_applied(self):
 347         if not os.path.isfile(self.__applied_file):
 348             raise StackException, 'Branch "%s" not initialised' % self.__name
 349         f = file(self.__applied_file)
 350         names = [line.strip() for line in f.readlines()]
 351         f.close()
 352         return names
 353
 354     def get_unapplied(self):
 355         if not os.path.isfile(self.__unapplied_file):
 356             raise StackException, 'Branch "%s" not initialised' % self.__name
 357         f = file(self.__unapplied_file)
 358         names = [line.strip() for line in f.readlines()]
 359         f.close()
 360         return names
 361
 362     def get_base_file(self):
 363         self.__begin_stack_check()
 364         return self.__base_file
 365
 366     def get_protected(self):
 367         return os.path.isfile(os.path.join(self.__series_dir, 'protected'))
 368
 369     def protect(self):
 370         protect_file = os.path.join(self.__series_dir, 'protected')
 371         if not os.path.isfile(protect_file):
 372             create_empty_file(protect_file)
 373
 374     def unprotect(self):
 375         protect_file = os.path.join(self.__series_dir, 'protected')
 376         if os.path.isfile(protect_file):
 377             os.remove(protect_file)
 378
 379     def get_description(self):
 380         if os.path.isfile(self.__descr_file):
 381             return read_string(self.__descr_file)
 382         else:
 383             return ''
 384
 385     def __patch_is_current(self, patch):
 386         return patch.get_name() == read_string(self.__current_file)
 387
 388     def __patch_applied(self, name):
 389         """Return true if the patch exists in the applied list
 390         """
 391         return name in self.get_applied()
 392
 393     def __patch_unapplied(self, name):
 394         """Return true if the patch exists in the unapplied list
 395         """
 396         return name in self.get_unapplied()
 397
 398     def __begin_stack_check(self):
 399         """Save the current HEAD into .git/refs/heads/base if the stack
 400         is empty
 401         """
 402         if len(self.get_applied()) == 0:
 403             head = git.get_head()
 404             write_string(self.__base_file, head)
 405
 406     def __end_stack_check(self):
 407         """Remove .git/refs/heads/base if the stack is empty.
 408         This warning should never happen
 409         """
 410         if len(self.get_applied()) == 0 \
 411            and read_string(self.__base_file) != git.get_head():
 412             print 'Warning: stack empty but the HEAD and base are different'
 413
 414     def head_top_equal(self):
 415         """Return true if the head and the top are the same
 416         """
 417         crt = self.get_current()
 418         if not crt:
 419             # we don't care, no patches applied
 420             return True
 421         return git.get_head() == Patch(crt, self.__patch_dir,
 422                                        self.__refs_dir).get_top()
 423
 424     def is_initialised(self):
 425         """Checks if series is already initialised
 426         """
 427         return os.path.isdir(self.__patch_dir)
 428
 429     def init(self, create_at=False):
 430         """Initialises the stgit series
 431         """
 432         bases_dir = os.path.join(self.__base_dir, 'refs', 'bases')
 433
 434         if os.path.exists(self.__patch_dir):
 435             raise StackException, self.__patch_dir + ' already exists'
 436         if os.path.exists(self.__refs_dir):
 437             raise StackException, self.__refs_dir + ' already exists'
 438         if os.path.exists(self.__base_file):
 439             raise StackException, self.__base_file + ' already exists'
 440
 441         if (create_at!=False):
 442             git.create_branch(self.__name, create_at)
 443
 444         os.makedirs(self.__patch_dir)
 445
 446         if not os.path.isdir(bases_dir):
 447             os.makedirs(bases_dir)
 448
 449         create_empty_file(self.__applied_file)
 450         create_empty_file(self.__unapplied_file)
 451         create_empty_file(self.__descr_file)
 452         os.makedirs(os.path.join(self.__series_dir, 'patches'))
 453         os.makedirs(self.__refs_dir)
 454         self.__begin_stack_check()
 455
 456     def convert(self):
 457         """Either convert to use a separate patch directory, or
 458         unconvert to place the patches in the same directory with
 459         series control files
 460         """
 461         if self.__patch_dir == self.__series_dir:
 462             print 'Converting old-style to new-style...',
 463             sys.stdout.flush()
 464
 465             self.__patch_dir = os.path.join(self.__series_dir, 'patches')
 466             os.makedirs(self.__patch_dir)
 467
 468             for p in self.get_applied() + self.get_unapplied():
 469                 src = os.path.join(self.__series_dir, p)
 470                 dest = os.path.join(self.__patch_dir, p)
 471                 os.rename(src, dest)
 472
 473             print 'done'
 474
 475         else:
 476             print 'Converting new-style to old-style...',
 477             sys.stdout.flush()
 478
 479             for p in self.get_applied() + self.get_unapplied():
 480                 src = os.path.join(self.__patch_dir, p)
 481                 dest = os.path.join(self.__series_dir, p)
 482                 os.rename(src, dest)
 483
 484             if not os.listdir(self.__patch_dir):
 485                 os.rmdir(self.__patch_dir)
 486                 print 'done'
 487             else:
 488                 print 'Patch directory %s is not empty.' % self.__name
 489
 490             self.__patch_dir = self.__series_dir
 491
 492     def rename(self, to_name):
 493         """Renames a series
 494         """
 495         to_stack = Series(to_name)
 496
 497         if to_stack.is_initialised():
 498             raise StackException, '"%s" already exists' % to_stack.get_branch()
 499         if os.path.exists(to_stack.__base_file):
 500             os.remove(to_stack.__base_file)
 501
 502         git.rename_branch(self.__name, to_name)
 503
 504         if os.path.isdir(self.__series_dir):
 505             os.rename(self.__series_dir, to_stack.__series_dir)
 506         if os.path.exists(self.__base_file):
 507             os.rename(self.__base_file, to_stack.__base_file)
 508
 509         self.__init__(to_name)
 510
 511     def clone(self, target_series):
 512         """Clones a series
 513         """
 514         base = read_string(self.get_base_file())
 515         Series(target_series).init(create_at = base)
 516         new_series = Series(target_series)
 517
 518         # generate an artificial description file
 519         write_string(new_series.__descr_file, 'clone of "%s"' % self.__name)
 520
 521         # clone self's entire series as unapplied patches
 522         patches = self.get_applied() + self.get_unapplied()
 523         patches.reverse()
 524         for p in patches:
 525             patch = self.get_patch(p)
 526             new_series.new_patch(p, message = patch.get_description(),
 527                                  can_edit = False, unapplied = True,
 528                                  bottom = patch.get_bottom(),
 529                                  top = patch.get_top(),
 530                                  author_name = patch.get_authname(),
 531                                  author_email = patch.get_authemail(),
 532                                  author_date = patch.get_authdate())
 533
 534         # fast forward the cloned series to self's top
 535         new_series.forward_patches(self.get_applied())
 536
 537     def delete(self, force = False):
 538         """Deletes an stgit series
 539         """
 540         if self.is_initialised():
 541             patches = self.get_unapplied() + self.get_applied()
 542             if not force and patches:
 543                 raise StackException, \
 544                       'Cannot delete: the series still contains patches'
 545             for p in patches:
 546                 Patch(p, self.__patch_dir, self.__refs_dir).delete()
 547
 548             if os.path.exists(self.__applied_file):
 549                 os.remove(self.__applied_file)
 550             if os.path.exists(self.__unapplied_file):
 551                 os.remove(self.__unapplied_file)
 552             if os.path.exists(self.__current_file):
 553                 os.remove(self.__current_file)
 554             if os.path.exists(self.__descr_file):
 555                 os.remove(self.__descr_file)
 556             if not os.listdir(self.__patch_dir):
 557                 os.rmdir(self.__patch_dir)
 558             else:
 559                 print 'Patch directory %s is not empty.' % self.__name
 560             if not os.listdir(self.__series_dir):
 561                 os.rmdir(self.__series_dir)
 562             else:
 563                 print 'Series directory %s is not empty.' % self.__name
 564             if not os.listdir(self.__refs_dir):
 565                 os.rmdir(self.__refs_dir)
 566             else:
 567                 print 'Refs directory %s is not empty.' % self.__refs_dir
 568
 569         if os.path.exists(self.__base_file):
 570             os.remove(self.__base_file)
 571
 572     def refresh_patch(self, files = None, message = None, edit = False,
 573                       show_patch = False,
 574                       cache_update = True,
 575                       author_name = None, author_email = None,
 576                       author_date = None,
 577                       committer_name = None, committer_email = None,
 578                       backup = False):
 579         """Generates a new commit for the given patch
 580         """
 581         name = self.get_current()
 582         if not name:
 583             raise StackException, 'No patches applied'
 584
 585         patch = Patch(name, self.__patch_dir, self.__refs_dir)
 586
 587         descr = patch.get_description()
 588         if not (message or descr):
 589             edit = True
 590             descr = ''
 591         elif message:
 592             descr = message
 593
 594         if not message and edit:
 595             descr = edit_file(self, descr.rstrip(), \
 596                               'Please edit the description for patch "%s" ' \
 597                               'above.' % name, show_patch)
 598
 599         if not author_name:
 600             author_name = patch.get_authname()
 601         if not author_email:
 602             author_email = patch.get_authemail()
 603         if not author_date:
 604             author_date = patch.get_authdate()
 605         if not committer_name:
 606             committer_name = patch.get_commname()
 607         if not committer_email:
 608             committer_email = patch.get_commemail()
 609
 610         bottom = patch.get_bottom()
 611
 612         commit_id = git.commit(files = files,
 613                                message = descr, parents = [bottom],
 614                                cache_update = cache_update,
 615                                allowempty = True,
 616                                author_name = author_name,
 617                                author_email = author_email,
 618                                author_date = author_date,
 619                                committer_name = committer_name,
 620                                committer_email = committer_email)
 621
 622         patch.set_bottom(bottom, backup = backup)
 623         patch.set_top(commit_id, backup = backup)
 624         patch.set_description(descr)
 625         patch.set_authname(author_name)
 626         patch.set_authemail(author_email)
 627         patch.set_authdate(author_date)
 628         patch.set_commname(committer_name)
 629         patch.set_commemail(committer_email)
 630
 631         return commit_id
 632
 633     def undo_refresh(self):
 634         """Undo the patch boundaries changes caused by 'refresh'
 635         """
 636         name = self.get_current()
 637         assert(name)
 638
 639         patch = Patch(name, self.__patch_dir, self.__refs_dir)
 640         old_bottom = patch.get_old_bottom()
 641         old_top = patch.get_old_top()
 642
 643         # the bottom of the patch is not changed by refresh. If the
 644         # old_bottom is different, there wasn't any previous 'refresh'
 645         # command (probably only a 'push')
 646         if old_bottom != patch.get_bottom() or old_top == patch.get_top():
 647             raise StackException, 'No refresh undo information available'
 648
 649         git.reset(tree_id = old_top, check_out = False)
 650         patch.restore_old_boundaries()
 651
 652     def new_patch(self, name, message = None, can_edit = True,
 653                   unapplied = False, show_patch = False,
 654                   top = None, bottom = None,
 655                   author_name = None, author_email = None, author_date = None,
 656                   committer_name = None, committer_email = None,
 657                   before_existing = False):
 658         """Creates a new patch
 659         """
 660         if self.__patch_applied(name) or self.__patch_unapplied(name):
 661             raise StackException, 'Patch "%s" already exists' % name
 662
 663         if not message and can_edit:
 664             descr = edit_file(self, None, \
 665                               'Please enter the description for patch "%s" ' \
 666                               'above.' % name, show_patch)
 667         else:
 668             descr = message
 669
 670         head = git.get_head()
 671
 672         self.__begin_stack_check()
 673
 674         patch = Patch(name, self.__patch_dir, self.__refs_dir)
 675         patch.create()
 676
 677         if bottom:
 678             patch.set_bottom(bottom)
 679         else:
 680             patch.set_bottom(head)
 681         if top:
 682             patch.set_top(top)
 683         else:
 684             patch.set_top(head)
 685
 686         patch.set_description(descr)
 687         patch.set_authname(author_name)
 688         patch.set_authemail(author_email)
 689         patch.set_authdate(author_date)
 690         patch.set_commname(committer_name)
 691         patch.set_commemail(committer_email)
 692
 693         if unapplied:
 694             patches = [patch.get_name()] + self.get_unapplied()
 695
 696             f = file(self.__unapplied_file, 'w+')
 697             f.writelines([line + '\n' for line in patches])
 698             f.close()
 699         else:
 700             if before_existing:
 701                 insert_string(self.__applied_file, patch.get_name())
 702                 if not self.get_current():
 703                     self.__set_current(name)
 704             else:
 705                 append_string(self.__applied_file, patch.get_name())
 706                 self.__set_current(name)
 707
 708     def delete_patch(self, name):
 709         """Deletes a patch
 710         """
 711         patch = Patch(name, self.__patch_dir, self.__refs_dir)
 712
 713         if self.__patch_is_current(patch):
 714             self.pop_patch(name)
 715         elif self.__patch_applied(name):
 716             raise StackException, 'Cannot remove an applied patch, "%s", ' \
 717                   'which is not current' % name
 718         elif not name in self.get_unapplied():
 719             raise StackException, 'Unknown patch "%s"' % name
 720
 721         patch.delete()
 722
 723         unapplied = self.get_unapplied()
 724         unapplied.remove(name)
 725         f = file(self.__unapplied_file, 'w+')
 726         f.writelines([line + '\n' for line in unapplied])
 727         f.close()
 728         self.__begin_stack_check()
 729
 730     def forward_patches(self, names):
 731         """Try to fast-forward an array of patches.
 732
 733         On return, patches in names[0:returned_value] have been pushed on the
 734         stack. Apply the rest with push_patch
 735         """
 736         unapplied = self.get_unapplied()
 737         self.__begin_stack_check()
 738
 739         forwarded = 0
 740         top = git.get_head()
 741
 742         for name in names:
 743             assert(name in unapplied)
 744
 745             patch = Patch(name, self.__patch_dir, self.__refs_dir)
 746
 747             head = top
 748             bottom = patch.get_bottom()
 749             top = patch.get_top()
 750
 751             # top != bottom always since we have a commit for each patch
 752             if head == bottom:
 753                 # reset the backup information
 754                 patch.set_bottom(head, backup = True)
 755                 patch.set_top(top, backup = True)
 756
 757             else:
 758                 head_tree = git.get_commit(head).get_tree()
 759                 bottom_tree = git.get_commit(bottom).get_tree()
 760                 if head_tree == bottom_tree:
 761                     # We must just reparent this patch and create a new commit
 762                     # for it
 763                     descr = patch.get_description()
 764                     author_name = patch.get_authname()
 765                     author_email = patch.get_authemail()
 766                     author_date = patch.get_authdate()
 767                     committer_name = patch.get_commname()
 768                     committer_email = patch.get_commemail()
 769
 770                     top_tree = git.get_commit(top).get_tree()
 771
 772                     top = git.commit(message = descr, parents = [head],
 773                                      cache_update = False,
 774                                      tree_id = top_tree,
 775                                      allowempty = True,
 776                                      author_name = author_name,
 777                                      author_email = author_email,
 778                                      author_date = author_date,
 779                                      committer_name = committer_name,
 780                                      committer_email = committer_email)
 781
 782                     patch.set_bottom(head, backup = True)
 783                     patch.set_top(top, backup = True)
 784                 else:
 785                     top = head
 786                     # stop the fast-forwarding, must do a real merge
 787                     break
 788
 789             forwarded+=1
 790             unapplied.remove(name)
 791
 792         if forwarded == 0:
 793             return 0
 794
 795         git.switch(top)
 796
 797         append_strings(self.__applied_file, names[0:forwarded])
 798
 799         f = file(self.__unapplied_file, 'w+')
 800         f.writelines([line + '\n' for line in unapplied])
 801         f.close()
 802
 803         self.__set_current(name)
 804
 805         return forwarded
 806
 807     def merged_patches(self, names):
 808         """Test which patches were merged upstream by reverse-applying
 809         them in reverse order. The function returns the list of
 810         patches detected to have been applied. The state of the tree
 811         is restored to the original one
 812         """
 813         patches = [Patch(name, self.__patch_dir, self.__refs_dir)
 814                    for name in names]
 815         patches.reverse()
 816
 817         merged = []
 818         for p in patches:
 819             if git.apply_diff(p.get_top(), p.get_bottom(), False):
 820                 merged.append(p.get_name())
 821         merged.reverse()
 822
 823         git.reset()
 824
 825         return merged
 826
 827     def push_patch(self, name, empty = False):
 828         """Pushes a patch on the stack
 829         """
 830         unapplied = self.get_unapplied()
 831         assert(name in unapplied)
 832
 833         self.__begin_stack_check()
 834
 835         patch = Patch(name, self.__patch_dir, self.__refs_dir)
 836
 837         head = git.get_head()
 838         bottom = patch.get_bottom()
 839         top = patch.get_top()
 840
 841         ex = None
 842         modified = False
 843
 844         # top != bottom always since we have a commit for each patch
 845         if empty:
 846             # just make an empty patch (top = bottom = HEAD). This
 847             # option is useful to allow undoing already merged
 848             # patches. The top is updated by refresh_patch since we
 849             # need an empty commit
 850             patch.set_bottom(head, backup = True)
 851             patch.set_top(head, backup = True)
 852             modified = True
 853         elif head == bottom:
 854             # reset the backup information
 855             patch.set_bottom(bottom, backup = True)
 856             patch.set_top(top, backup = True)
 857
 858             git.switch(top)
 859         else:
 860             # new patch needs to be refreshed.
 861             # The current patch is empty after merge.
 862             patch.set_bottom(head, backup = True)
 863             patch.set_top(head, backup = True)
 864
 865             # Try the fast applying first. If this fails, fall back to the
 866             # three-way merge
 867             if not git.apply_diff(bottom, top):
 868                 # if git.apply_diff() fails, the patch requires a diff3
 869                 # merge and can be reported as modified
 870                 modified = True
 871
 872                 # merge can fail but the patch needs to be pushed
 873                 try:
 874                     git.merge(bottom, head, top)
 875                 except git.GitException, ex:
 876                     print >> sys.stderr, \
 877                           'The merge failed during "push". ' \
 878                           'Use "refresh" after fixing the conflicts'
 879
 880         append_string(self.__applied_file, name)
 881
 882         unapplied.remove(name)
 883         f = file(self.__unapplied_file, 'w+')
 884         f.writelines([line + '\n' for line in unapplied])
 885         f.close()
 886
 887         self.__set_current(name)
 888
 889         # head == bottom case doesn't need to refresh the patch
 890         if empty or head != bottom:
 891             if not ex:
 892                 # if the merge was OK and no conflicts, just refresh the patch
 893                 # The GIT cache was already updated by the merge operation
 894                 self.refresh_patch(cache_update = False)
 895             else:
 896                 raise StackException, str(ex)
 897
 898         return modified
 899
 900     def undo_push(self):
 901         name = self.get_current()
 902         assert(name)
 903
 904         patch = Patch(name, self.__patch_dir, self.__refs_dir)
 905         old_bottom = patch.get_old_bottom()
 906         old_top = patch.get_old_top()
 907
 908         # the top of the patch is changed by a push operation only
 909         # together with the bottom (otherwise the top was probably
 910         # modified by 'refresh'). If they are both unchanged, there
 911         # was a fast forward
 912         if old_bottom == patch.get_bottom() and old_top != patch.get_top():
 913             raise StackException, 'No push undo information available'
 914
 915         git.reset()
 916         self.pop_patch(name)
 917         return patch.restore_old_boundaries()
 918
 919     def pop_patch(self, name):
 920         """Pops the top patch from the stack
 921         """
 922         applied = self.get_applied()
 923         applied.reverse()
 924         assert(name in applied)
 925
 926         patch = Patch(name, self.__patch_dir, self.__refs_dir)
 927
 928         git.switch(patch.get_bottom())
 929
 930         # save the new applied list
 931         idx = applied.index(name) + 1
 932
 933         popped = applied[:idx]
 934         popped.reverse()
 935         unapplied = popped + self.get_unapplied()
 936
 937         f = file(self.__unapplied_file, 'w+')
 938         f.writelines([line + '\n' for line in unapplied])
 939         f.close()
 940
 941         del applied[:idx]
 942         applied.reverse()
 943
 944         f = file(self.__applied_file, 'w+')
 945         f.writelines([line + '\n' for line in applied])
 946         f.close()
 947
 948         if applied == []:
 949             self.__set_current(None)
 950         else:
 951             self.__set_current(applied[-1])
 952
 953         self.__end_stack_check()
 954
 955     def empty_patch(self, name):
 956         """Returns True if the patch is empty
 957         """
 958         patch = Patch(name, self.__patch_dir, self.__refs_dir)
 959         bottom = patch.get_bottom()
 960         top = patch.get_top()
 961
 962         if bottom == top:
 963             return True
 964         elif git.get_commit(top).get_tree() \
 965                  == git.get_commit(bottom).get_tree():
 966             return True
 967
 968         return False
 969
 970     def rename_patch(self, oldname, newname):
 971         applied = self.get_applied()
 972         unapplied = self.get_unapplied()
 973
 974         if oldname == newname:
 975             raise StackException, '"To" name and "from" name are the same'
 976
 977         if newname in applied or newname in unapplied:
 978             raise StackException, 'Patch "%s" already exists' % newname
 979
 980         if oldname in unapplied:
 981             Patch(oldname, self.__patch_dir, self.__refs_dir).rename(newname)
 982             unapplied[unapplied.index(oldname)] = newname
 983
 984             f = file(self.__unapplied_file, 'w+')
 985             f.writelines([line + '\n' for line in unapplied])
 986             f.close()
 987         elif oldname in applied:
 988             Patch(oldname, self.__patch_dir, self.__refs_dir).rename(newname)
 989             if oldname == self.get_current():
 990                 self.__set_current(newname)
 991
 992             applied[applied.index(oldname)] = newname
 993
 994             f = file(self.__applied_file, 'w+')
 995             f.writelines([line + '\n' for line in applied])
 996             f.close()
 997         else:
 998             raise StackException, 'Unknown patch "%s"' % oldname