mdw@git.distorted.org.uk Git - stgit/blob - stgit/git.py

   1 """Python GIT interface
   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, re, gitmergeonefile
  22 from shutil import copyfile
  23
  24 from stgit.exception import *
  25 from stgit import basedir
  26 from stgit.utils import *
  27 from stgit.out import *
  28 from stgit.run import *
  29 from stgit.config import config
  30
  31 # git exception class
  32 class GitException(StgException):
  33     pass
  34
  35 # When a subprocess has a problem, we want the exception to be a
  36 # subclass of GitException.
  37 class GitRunException(GitException):
  38     pass
  39 class GRun(Run):
  40     exc = GitRunException
  41
  42
  43 #
  44 # Classes
  45 #
  46
  47 class Person:
  48     """An author, committer, etc."""
  49     def __init__(self, name = None, email = None, date = '',
  50                  desc = None):
  51         self.name = self.email = self.date = None
  52         if name or email or date:
  53             assert not desc
  54             self.name = name
  55             self.email = email
  56             self.date = date
  57         elif desc:
  58             assert not (name or email or date)
  59             def parse_desc(s):
  60                 m = re.match(r'^(.+)<(.+)>(.*)$', s)
  61                 assert m
  62                 return [x.strip() or None for x in m.groups()]
  63             self.name, self.email, self.date = parse_desc(desc)
  64     def set_name(self, val):
  65         if val:
  66             self.name = val
  67     def set_email(self, val):
  68         if val:
  69             self.email = val
  70     def set_date(self, val):
  71         if val:
  72             self.date = val
  73     def __str__(self):
  74         if self.name and self.email:
  75             return '%s <%s>' % (self.name, self.email)
  76         else:
  77             raise GitException, 'not enough identity data'
  78
  79 class Commit:
  80     """Handle the commit objects
  81     """
  82     def __init__(self, id_hash):
  83         self.__id_hash = id_hash
  84
  85         lines = GRun('git-cat-file', 'commit', id_hash).output_lines()
  86         for i in range(len(lines)):
  87             line = lines[i]
  88             if not line:
  89                 break # we've seen all the header fields
  90             key, val = line.split(' ', 1)
  91             if key == 'tree':
  92                 self.__tree = val
  93             elif key == 'author':
  94                 self.__author = val
  95             elif key == 'committer':
  96                 self.__committer = val
  97             else:
  98                 pass # ignore other headers
  99         self.__log = '\n'.join(lines[i+1:])
 100
 101     def get_id_hash(self):
 102         return self.__id_hash
 103
 104     def get_tree(self):
 105         return self.__tree
 106
 107     def get_parent(self):
 108         parents = self.get_parents()
 109         if parents:
 110             return parents[0]
 111         else:
 112             return None
 113
 114     def get_parents(self):
 115         return GRun('git-rev-list', '--parents', '--max-count=1', self.__id_hash
 116                     ).output_one_line().split()[1:]
 117
 118     def get_author(self):
 119         return self.__author
 120
 121     def get_committer(self):
 122         return self.__committer
 123
 124     def get_log(self):
 125         return self.__log
 126
 127     def __str__(self):
 128         return self.get_id_hash()
 129
 130 # dictionary of Commit objects, used to avoid multiple calls to git
 131 __commits = dict()
 132
 133 #
 134 # Functions
 135 #
 136
 137 def get_commit(id_hash):
 138     """Commit objects factory. Save/look-up them in the __commits
 139     dictionary
 140     """
 141     global __commits
 142
 143     if id_hash in __commits:
 144         return __commits[id_hash]
 145     else:
 146         commit = Commit(id_hash)
 147         __commits[id_hash] = commit
 148         return commit
 149
 150 def get_conflicts():
 151     """Return the list of file conflicts
 152     """
 153     conflicts_file = os.path.join(basedir.get(), 'conflicts')
 154     if os.path.isfile(conflicts_file):
 155         f = file(conflicts_file)
 156         names = [line.strip() for line in f.readlines()]
 157         f.close()
 158         return names
 159     else:
 160         return None
 161
 162 def exclude_files():
 163     files = [os.path.join(basedir.get(), 'info', 'exclude')]
 164     user_exclude = config.get('core.excludesfile')
 165     if user_exclude:
 166         files.append(user_exclude)
 167     return files
 168
 169 def tree_status(files = None, tree_id = 'HEAD', unknown = False,
 170                   noexclude = True, verbose = False, diff_flags = []):
 171     """Get the status of all changed files, or of a selected set of
 172     files. Returns a list of pairs - (status, filename).
 173
 174     If 'files' is None, it will check all files, and optionally all
 175     unknown files.  If 'files' is a list, it will only check the files
 176     in the list.
 177     """
 178     assert files == None or not unknown
 179
 180     if verbose:
 181         out.start('Checking for changes in the working directory')
 182
 183     refresh_index()
 184
 185     cache_files = []
 186
 187     # unknown files
 188     if unknown:
 189         cmd = ['git-ls-files', '-z', '--others', '--directory',
 190                '--no-empty-directory']
 191         if not noexclude:
 192             cmd += ['--exclude=%s' % s for s in
 193                     ['*.[ao]', '*.pyc', '.*', '*~', '#*', 'TAGS', 'tags']]
 194             cmd += ['--exclude-per-directory=.gitignore']
 195             cmd += ['--exclude-from=%s' % fn
 196                     for fn in exclude_files()
 197                     if os.path.exists(fn)]
 198
 199         lines = GRun(*cmd).raw_output().split('\0')
 200         cache_files += [('?', line) for line in lines if line]
 201
 202     # conflicted files
 203     conflicts = get_conflicts()
 204     if not conflicts:
 205         conflicts = []
 206     cache_files += [('C', filename) for filename in conflicts
 207                     if files == None or filename in files]
 208
 209     # the rest
 210     args = diff_flags + [tree_id]
 211     if files != None:
 212         args += ['--'] + files
 213     for line in GRun('git-diff-index', *args).output_lines():
 214         fs = tuple(line.rstrip().split(' ',4)[-1].split('\t',1))
 215         if fs[1] not in conflicts:
 216             cache_files.append(fs)
 217
 218     if verbose:
 219         out.done()
 220
 221     assert files == None or set(f for s,f in cache_files) <= set(files)
 222     return cache_files
 223
 224 def local_changes(verbose = True):
 225     """Return true if there are local changes in the tree
 226     """
 227     return len(tree_status(verbose = verbose)) != 0
 228
 229 def get_heads():
 230     heads = []
 231     hr = re.compile(r'^[0-9a-f]{40} refs/heads/(.+)$')
 232     for line in GRun('git-show-ref', '--heads').output_lines():
 233         m = hr.match(line)
 234         heads.append(m.group(1))
 235     return heads
 236
 237 # HEAD value cached
 238 __head = None
 239
 240 def get_head():
 241     """Verifies the HEAD and returns the SHA1 id that represents it
 242     """
 243     global __head
 244
 245     if not __head:
 246         __head = rev_parse('HEAD')
 247     return __head
 248
 249 def get_head_file():
 250     """Returns the name of the file pointed to by the HEAD link
 251     """
 252     return strip_prefix('refs/heads/',
 253                         GRun('git-symbolic-ref', 'HEAD').output_one_line())
 254
 255 def set_head_file(ref):
 256     """Resets HEAD to point to a new ref
 257     """
 258     # head cache flushing is needed since we might have a different value
 259     # in the new head
 260     __clear_head_cache()
 261     try:
 262         GRun('git-symbolic-ref', 'HEAD', 'refs/heads/%s' % ref).run()
 263     except GitRunException:
 264         raise GitException, 'Could not set head to "%s"' % ref
 265
 266 def set_ref(ref, val):
 267     """Point ref at a new commit object."""
 268     try:
 269         GRun('git-update-ref', ref, val).run()
 270     except GitRunException:
 271         raise GitException, 'Could not update %s to "%s".' % (ref, val)
 272
 273 def set_branch(branch, val):
 274     set_ref('refs/heads/%s' % branch, val)
 275
 276 def __set_head(val):
 277     """Sets the HEAD value
 278     """
 279     global __head
 280
 281     if not __head or __head != val:
 282         set_ref('HEAD', val)
 283         __head = val
 284
 285     # only allow SHA1 hashes
 286     assert(len(__head) == 40)
 287
 288 def __clear_head_cache():
 289     """Sets the __head to None so that a re-read is forced
 290     """
 291     global __head
 292
 293     __head = None
 294
 295 def refresh_index():
 296     """Refresh index with stat() information from the working directory.
 297     """
 298     GRun('git-update-index', '-q', '--unmerged', '--refresh').run()
 299
 300 def rev_parse(git_id):
 301     """Parse the string and return a verified SHA1 id
 302     """
 303     try:
 304         return GRun('git-rev-parse', '--verify', git_id).output_one_line()
 305     except GitRunException:
 306         raise GitException, 'Unknown revision: %s' % git_id
 307
 308 def ref_exists(ref):
 309     try:
 310         rev_parse(ref)
 311         return True
 312     except GitException:
 313         return False
 314
 315 def branch_exists(branch):
 316     return ref_exists('refs/heads/%s' % branch)
 317
 318 def create_branch(new_branch, tree_id = None):
 319     """Create a new branch in the git repository
 320     """
 321     if branch_exists(new_branch):
 322         raise GitException, 'Branch "%s" already exists' % new_branch
 323
 324     current_head = get_head()
 325     set_head_file(new_branch)
 326     __set_head(current_head)
 327
 328     # a checkout isn't needed if new branch points to the current head
 329     if tree_id:
 330         switch(tree_id)
 331
 332     if os.path.isfile(os.path.join(basedir.get(), 'MERGE_HEAD')):
 333         os.remove(os.path.join(basedir.get(), 'MERGE_HEAD'))
 334
 335 def switch_branch(new_branch):
 336     """Switch to a git branch
 337     """
 338     global __head
 339
 340     if not branch_exists(new_branch):
 341         raise GitException, 'Branch "%s" does not exist' % new_branch
 342
 343     tree_id = rev_parse('refs/heads/%s^{commit}' % new_branch)
 344     if tree_id != get_head():
 345         refresh_index()
 346         try:
 347             GRun('git-read-tree', '-u', '-m', get_head(), tree_id).run()
 348         except GitRunException:
 349             raise GitException, 'git-read-tree failed (local changes maybe?)'
 350         __head = tree_id
 351     set_head_file(new_branch)
 352
 353     if os.path.isfile(os.path.join(basedir.get(), 'MERGE_HEAD')):
 354         os.remove(os.path.join(basedir.get(), 'MERGE_HEAD'))
 355
 356 def delete_ref(ref):
 357     if not ref_exists(ref):
 358         raise GitException, '%s does not exist' % ref
 359     sha1 = GRun('git-show-ref', '-s', ref).output_one_line()
 360     try:
 361         GRun('git-update-ref', '-d', ref, sha1).run()
 362     except GitRunException:
 363         raise GitException, 'Failed to delete ref %s' % ref
 364
 365 def delete_branch(name):
 366     delete_ref('refs/heads/%s' % name)
 367
 368 def rename_ref(from_ref, to_ref):
 369     if not ref_exists(from_ref):
 370         raise GitException, '"%s" does not exist' % from_ref
 371     if ref_exists(to_ref):
 372         raise GitException, '"%s" already exists' % to_ref
 373
 374     sha1 = GRun('git-show-ref', '-s', from_ref).output_one_line()
 375     try:
 376         GRun('git-update-ref', to_ref, sha1, '0'*40).run()
 377     except GitRunException:
 378         raise GitException, 'Failed to create new ref %s' % to_ref
 379     try:
 380         GRun('git-update-ref', '-d', from_ref, sha1).run()
 381     except GitRunException:
 382         raise GitException, 'Failed to delete ref %s' % from_ref
 383
 384 def rename_branch(from_name, to_name):
 385     """Rename a git branch."""
 386     rename_ref('refs/heads/%s' % from_name, 'refs/heads/%s' % to_name)
 387     if get_head_file() == from_name:
 388         set_head_file(to_name)
 389     reflog_dir = os.path.join(basedir.get(), 'logs', 'refs', 'heads')
 390     if os.path.exists(reflog_dir) \
 391            and os.path.exists(os.path.join(reflog_dir, from_name)):
 392         rename(reflog_dir, from_name, to_name)
 393
 394 def add(names):
 395     """Add the files or recursively add the directory contents
 396     """
 397     # generate the file list
 398     files = []
 399     for i in names:
 400         if not os.path.exists(i):
 401             raise GitException, 'Unknown file or directory: %s' % i
 402
 403         if os.path.isdir(i):
 404             # recursive search. We only add files
 405             for root, dirs, local_files in os.walk(i):
 406                 for name in [os.path.join(root, f) for f in local_files]:
 407                     if os.path.isfile(name):
 408                         files.append(os.path.normpath(name))
 409         elif os.path.isfile(i):
 410             files.append(os.path.normpath(i))
 411         else:
 412             raise GitException, '%s is not a file or directory' % i
 413
 414     if files:
 415         try:
 416             GRun('git-update-index', '--add', '--').xargs(files)
 417         except GitRunException:
 418             raise GitException, 'Unable to add file'
 419
 420 def __copy_single(source, target, target2=''):
 421     """Copy file or dir named 'source' to name target+target2"""
 422
 423     # "source" (file or dir) must match one or more git-controlled file
 424     realfiles = GRun('git-ls-files', source).output_lines()
 425     if len(realfiles) == 0:
 426         raise GitException, '"%s" matches no git-controled files' % source
 427
 428     if os.path.isdir(source):
 429         # physically copy the files, and record them to add them in one run
 430         newfiles = []
 431         re_string='^'+source+'/(.*)$'
 432         prefix_regexp = re.compile(re_string)
 433         for f in [f.strip() for f in realfiles]:
 434             m = prefix_regexp.match(f)
 435             if not m:
 436                 raise Exception, '"%s" does not match "%s"' % (f, re_string)
 437             newname = target+target2+'/'+m.group(1)
 438             if not os.path.exists(os.path.dirname(newname)):
 439                 os.makedirs(os.path.dirname(newname))
 440             copyfile(f, newname)
 441             newfiles.append(newname)
 442
 443         add(newfiles)
 444     else: # files, symlinks, ...
 445         newname = target+target2
 446         copyfile(source, newname)
 447         add([newname])
 448
 449
 450 def copy(filespecs, target):
 451     if os.path.isdir(target):
 452         # target is a directory: copy each entry on the command line,
 453         # with the same name, into the target
 454         target = target.rstrip('/')
 455
 456         # first, check that none of the children of the target
 457         # matching the command line aleady exist
 458         for filespec in filespecs:
 459             entry = target+ '/' + os.path.basename(filespec.rstrip('/'))
 460             if os.path.exists(entry):
 461                 raise GitException, 'Target "%s" already exists' % entry
 462
 463         for filespec in filespecs:
 464             filespec = filespec.rstrip('/')
 465             basename = '/' + os.path.basename(filespec)
 466             __copy_single(filespec, target, basename)
 467
 468     elif os.path.exists(target):
 469         raise GitException, 'Target "%s" exists but is not a directory' % target
 470     elif len(filespecs) != 1:
 471         raise GitException, 'Cannot copy more than one file to non-directory'
 472
 473     else:
 474         # at this point: len(filespecs)==1 and target does not exist
 475
 476         # check target directory
 477         targetdir = os.path.dirname(target)
 478         if targetdir != '' and not os.path.isdir(targetdir):
 479             raise GitException, 'Target directory "%s" does not exist' % targetdir
 480
 481         __copy_single(filespecs[0].rstrip('/'), target)
 482
 483
 484 def rm(files, force = False):
 485     """Remove a file from the repository
 486     """
 487     if not force:
 488         for f in files:
 489             if os.path.exists(f):
 490                 raise GitException, '%s exists. Remove it first' %f
 491         if files:
 492             GRun('git-update-index', '--remove', '--').xargs(files)
 493     else:
 494         if files:
 495             GRun('git-update-index', '--force-remove', '--').xargs(files)
 496
 497 # Persons caching
 498 __user = None
 499 __author = None
 500 __committer = None
 501
 502 def user():
 503     """Return the user information.
 504     """
 505     global __user
 506     if not __user:
 507         name=config.get('user.name')
 508         email=config.get('user.email')
 509         __user = Person(name, email)
 510     return __user;
 511
 512 def author():
 513     """Return the author information.
 514     """
 515     global __author
 516     if not __author:
 517         try:
 518             # the environment variables take priority over config
 519             try:
 520                 date = os.environ['GIT_AUTHOR_DATE']
 521             except KeyError:
 522                 date = ''
 523             __author = Person(os.environ['GIT_AUTHOR_NAME'],
 524                               os.environ['GIT_AUTHOR_EMAIL'],
 525                               date)
 526         except KeyError:
 527             __author = user()
 528     return __author
 529
 530 def committer():
 531     """Return the author information.
 532     """
 533     global __committer
 534     if not __committer:
 535         try:
 536             # the environment variables take priority over config
 537             try:
 538                 date = os.environ['GIT_COMMITTER_DATE']
 539             except KeyError:
 540                 date = ''
 541             __committer = Person(os.environ['GIT_COMMITTER_NAME'],
 542                                  os.environ['GIT_COMMITTER_EMAIL'],
 543                                  date)
 544         except KeyError:
 545             __committer = user()
 546     return __committer
 547
 548 def update_cache(files = None, force = False):
 549     """Update the cache information for the given files
 550     """
 551     cache_files = tree_status(files, verbose = False)
 552
 553     # everything is up-to-date
 554     if len(cache_files) == 0:
 555         return False
 556
 557     # check for unresolved conflicts
 558     if not force and [x for x in cache_files
 559                       if x[0] not in ['M', 'N', 'A', 'D']]:
 560         raise GitException, 'Updating cache failed: unresolved conflicts'
 561
 562     # update the cache
 563     add_files = [x[1] for x in cache_files if x[0] in ['N', 'A']]
 564     rm_files =  [x[1] for x in cache_files if x[0] in ['D']]
 565     m_files =   [x[1] for x in cache_files if x[0] in ['M']]
 566
 567     GRun('git-update-index', '--add', '--').xargs(add_files)
 568     GRun('git-update-index', '--force-remove', '--').xargs(rm_files)
 569     GRun('git-update-index', '--').xargs(m_files)
 570
 571     return True
 572
 573 def commit(message, files = None, parents = None, allowempty = False,
 574            cache_update = True, tree_id = None, set_head = False,
 575            author_name = None, author_email = None, author_date = None,
 576            committer_name = None, committer_email = None):
 577     """Commit the current tree to repository
 578     """
 579     if not parents:
 580         parents = []
 581
 582     # Get the tree status
 583     if cache_update and parents != []:
 584         changes = update_cache(files)
 585         if not changes and not allowempty:
 586             raise GitException, 'No changes to commit'
 587
 588     # get the commit message
 589     if not message:
 590         message = '\n'
 591     elif message[-1:] != '\n':
 592         message += '\n'
 593
 594     # write the index to repository
 595     if tree_id == None:
 596         tree_id = GRun('git-write-tree').output_one_line()
 597         set_head = True
 598
 599     # the commit
 600     env = {}
 601     if author_name:
 602         env['GIT_AUTHOR_NAME'] = author_name
 603     if author_email:
 604         env['GIT_AUTHOR_EMAIL'] = author_email
 605     if author_date:
 606         env['GIT_AUTHOR_DATE'] = author_date
 607     if committer_name:
 608         env['GIT_COMMITTER_NAME'] = committer_name
 609     if committer_email:
 610         env['GIT_COMMITTER_EMAIL'] = committer_email
 611     commit_id = GRun('git-commit-tree', tree_id,
 612                      *sum([['-p', p] for p in parents], [])
 613                      ).env(env).raw_input(message).output_one_line()
 614     if set_head:
 615         __set_head(commit_id)
 616
 617     return commit_id
 618
 619 def apply_diff(rev1, rev2, check_index = True, files = None):
 620     """Apply the diff between rev1 and rev2 onto the current
 621     index. This function doesn't need to raise an exception since it
 622     is only used for fast-pushing a patch. If this operation fails,
 623     the pushing would fall back to the three-way merge.
 624     """
 625     if check_index:
 626         index_opt = ['--index']
 627     else:
 628         index_opt = []
 629
 630     if not files:
 631         files = []
 632
 633     diff_str = diff(files, rev1, rev2)
 634     if diff_str:
 635         try:
 636             GRun('git-apply', *index_opt).raw_input(
 637                 diff_str).discard_stderr().no_output()
 638         except GitRunException:
 639             return False
 640
 641     return True
 642
 643 def merge(base, head1, head2, recursive = False):
 644     """Perform a 3-way merge between base, head1 and head2 into the
 645     local tree
 646     """
 647     refresh_index()
 648
 649     err_output = None
 650     if recursive:
 651         # this operation tracks renames but it is slower (used in
 652         # general when pushing or picking patches)
 653         try:
 654             # discard output to mask the verbose prints of the tool
 655             GRun('git-merge-recursive', base, '--', head1, head2
 656                  ).discard_output()
 657         except GitRunException, ex:
 658             err_output = str(ex)
 659             pass
 660     else:
 661         # the fast case where we don't track renames (used when the
 662         # distance between base and heads is small, i.e. folding or
 663         # synchronising patches)
 664         try:
 665             GRun('git-read-tree', '-u', '-m', '--aggressive',
 666                  base, head1, head2).run()
 667         except GitRunException:
 668             raise GitException, 'git-read-tree failed (local changes maybe?)'
 669
 670     # check the index for unmerged entries
 671     files = {}
 672     stages_re = re.compile('^([0-7]+) ([0-9a-f]{40}) ([1-3])\t(.*)$', re.S)
 673
 674     for line in GRun('git-ls-files', '--unmerged', '--stage', '-z'
 675                      ).raw_output().split('\0'):
 676         if not line:
 677             continue
 678
 679         mode, hash, stage, path = stages_re.findall(line)[0]
 680
 681         if not path in files:
 682             files[path] = {}
 683             files[path]['1'] = ('', '')
 684             files[path]['2'] = ('', '')
 685             files[path]['3'] = ('', '')
 686
 687         files[path][stage] = (mode, hash)
 688
 689     if err_output and not files:
 690         # if no unmerged files, there was probably a different type of
 691         # error and we have to abort the merge
 692         raise GitException, err_output
 693
 694     # merge the unmerged files
 695     errors = False
 696     for path in files:
 697         # remove additional files that might be generated for some
 698         # newer versions of GIT
 699         for suffix in [base, head1, head2]:
 700             if not suffix:
 701                 continue
 702             fname = path + '~' + suffix
 703             if os.path.exists(fname):
 704                 os.remove(fname)
 705
 706         stages = files[path]
 707         if gitmergeonefile.merge(stages['1'][1], stages['2'][1],
 708                                  stages['3'][1], path, stages['1'][0],
 709                                  stages['2'][0], stages['3'][0]) != 0:
 710             errors = True
 711
 712     if errors:
 713         raise GitException, 'GIT index merging failed (possible conflicts)'
 714
 715 def diff(files = None, rev1 = 'HEAD', rev2 = None, diff_flags = []):
 716     """Show the diff between rev1 and rev2
 717     """
 718     if not files:
 719         files = []
 720
 721     if rev1 and rev2:
 722         return GRun('git-diff-tree', '-p',
 723                     *(diff_flags + [rev1, rev2, '--'] + files)).raw_output()
 724     elif rev1 or rev2:
 725         refresh_index()
 726         if rev2:
 727             return GRun('git-diff-index', '-p', '-R',
 728                         *(diff_flags + [rev2, '--'] + files)).raw_output()
 729         else:
 730             return GRun('git-diff-index', '-p',
 731                         *(diff_flags + [rev1, '--'] + files)).raw_output()
 732     else:
 733         return ''
 734
 735 # TODO: take another parameter representing a diff string as we
 736 # usually invoke git.diff() form the calling functions
 737 def diffstat(files = None, rev1 = 'HEAD', rev2 = None):
 738     """Return the diffstat between rev1 and rev2."""
 739     return GRun('git-apply', '--stat', '--summary'
 740                 ).raw_input(diff(files, rev1, rev2)).raw_output()
 741
 742 def files(rev1, rev2, diff_flags = []):
 743     """Return the files modified between rev1 and rev2
 744     """
 745
 746     result = []
 747     for line in GRun('git-diff-tree', *(diff_flags + ['-r', rev1, rev2])
 748                      ).output_lines():
 749         result.append('%s %s' % tuple(line.split(' ', 4)[-1].split('\t', 1)))
 750
 751     return '\n'.join(result)
 752
 753 def barefiles(rev1, rev2):
 754     """Return the files modified between rev1 and rev2, without status info
 755     """
 756
 757     result = []
 758     for line in GRun('git-diff-tree', '-r', rev1, rev2).output_lines():
 759         result.append(line.split(' ', 4)[-1].split('\t', 1)[-1])
 760
 761     return '\n'.join(result)
 762
 763 def pretty_commit(commit_id = 'HEAD', diff_flags = []):
 764     """Return a given commit (log + diff)
 765     """
 766     return GRun('git-diff-tree',
 767                 *(diff_flags
 768                   + ['--cc', '--always', '--pretty', '-r', commit_id])
 769                 ).raw_output()
 770
 771 def checkout(files = None, tree_id = None, force = False):
 772     """Check out the given or all files
 773     """
 774     if tree_id:
 775         try:
 776             GRun('git-read-tree', '--reset', tree_id).run()
 777         except GitRunException:
 778             raise GitException, 'Failed git-read-tree --reset %s' % tree_id
 779
 780     cmd = ['git-checkout-index', '-q', '-u']
 781     if force:
 782         cmd.append('-f')
 783     if files:
 784         GRun(*(cmd + ['--'])).xargs(files)
 785     else:
 786         GRun(*(cmd + ['-a'])).run()
 787
 788 def switch(tree_id, keep = False):
 789     """Switch the tree to the given id
 790     """
 791     if not keep:
 792         refresh_index()
 793         try:
 794             GRun('git-read-tree', '-u', '-m', get_head(), tree_id).run()
 795         except GitRunException:
 796             raise GitException, 'git-read-tree failed (local changes maybe?)'
 797
 798     __set_head(tree_id)
 799
 800 def reset(files = None, tree_id = None, check_out = True):
 801     """Revert the tree changes relative to the given tree_id. It removes
 802     any local changes
 803     """
 804     if not tree_id:
 805         tree_id = get_head()
 806
 807     if check_out:
 808         cache_files = tree_status(files, tree_id)
 809         # files which were added but need to be removed
 810         rm_files =  [x[1] for x in cache_files if x[0] in ['A']]
 811
 812         checkout(files, tree_id, True)
 813         # checkout doesn't remove files
 814         map(os.remove, rm_files)
 815
 816     # if the reset refers to the whole tree, switch the HEAD as well
 817     if not files:
 818         __set_head(tree_id)
 819
 820 def fetch(repository = 'origin', refspec = None):
 821     """Fetches changes from the remote repository, using 'git-fetch'
 822     by default.
 823     """
 824     # we update the HEAD
 825     __clear_head_cache()
 826
 827     args = [repository]
 828     if refspec:
 829         args.append(refspec)
 830
 831     command = config.get('branch.%s.stgit.fetchcmd' % get_head_file()) or \
 832               config.get('stgit.fetchcmd')
 833     GRun(*(command.split() + args)).run()
 834
 835 def pull(repository = 'origin', refspec = None):
 836     """Fetches changes from the remote repository, using 'git-pull'
 837     by default.
 838     """
 839     # we update the HEAD
 840     __clear_head_cache()
 841
 842     args = [repository]
 843     if refspec:
 844         args.append(refspec)
 845
 846     command = config.get('branch.%s.stgit.pullcmd' % get_head_file()) or \
 847               config.get('stgit.pullcmd')
 848     GRun(*(command.split() + args)).run()
 849
 850 def rebase(tree_id = None):
 851     """Rebase the current tree to the give tree_id. The tree_id
 852     argument may be something other than a GIT id if an external
 853     command is invoked.
 854     """
 855     command = config.get('branch.%s.stgit.rebasecmd' % get_head_file()) \
 856                 or config.get('stgit.rebasecmd')
 857     if tree_id:
 858         args = [tree_id]
 859     elif command:
 860         args = []
 861     else:
 862         raise GitException, 'Default rebasing requires a commit id'
 863     if command:
 864         # clear the HEAD cache as the custom rebase command will update it
 865         __clear_head_cache()
 866         GRun(*(command.split() + args)).run()
 867     else:
 868         # default rebasing
 869         reset(tree_id = tree_id)
 870
 871 def repack():
 872     """Repack all objects into a single pack
 873     """
 874     GRun('git-repack', '-a', '-d', '-f').run()
 875
 876 def apply_patch(filename = None, diff = None, base = None,
 877                 fail_dump = True):
 878     """Apply a patch onto the current or given index. There must not
 879     be any local changes in the tree, otherwise the command fails
 880     """
 881     if diff is None:
 882         if filename:
 883             f = file(filename)
 884         else:
 885             f = sys.stdin
 886         diff = f.read()
 887         if filename:
 888             f.close()
 889
 890     if base:
 891         orig_head = get_head()
 892         switch(base)
 893     else:
 894         refresh_index()
 895
 896     try:
 897         GRun('git-apply', '--index').raw_input(diff).no_output()
 898     except GitRunException:
 899         if base:
 900             switch(orig_head)
 901         if fail_dump:
 902             # write the failed diff to a file
 903             f = file('.stgit-failed.patch', 'w+')
 904             f.write(diff)
 905             f.close()
 906             out.warn('Diff written to the .stgit-failed.patch file')
 907
 908         raise
 909
 910     if base:
 911         top = commit(message = 'temporary commit used for applying a patch',
 912                      parents = [base])
 913         switch(orig_head)
 914         merge(base, orig_head, top)
 915
 916 def clone(repository, local_dir):
 917     """Clone a remote repository. At the moment, just use the
 918     'git-clone' script
 919     """
 920     GRun('git-clone', repository, local_dir).run()
 921
 922 def modifying_revs(files, base_rev, head_rev):
 923     """Return the revisions from the list modifying the given files."""
 924     return GRun('git-rev-list', '%s..%s' % (base_rev, head_rev), '--', *files
 925                 ).output_lines()
 926
 927 def refspec_localpart(refspec):
 928     m = re.match('^[^:]*:([^:]*)$', refspec)
 929     if m:
 930         return m.group(1)
 931     else:
 932         raise GitException, 'Cannot parse refspec "%s"' % line
 933
 934 def refspec_remotepart(refspec):
 935     m = re.match('^([^:]*):[^:]*$', refspec)
 936     if m:
 937         return m.group(1)
 938     else:
 939         raise GitException, 'Cannot parse refspec "%s"' % line
 940
 941
 942 def __remotes_from_config():
 943     return config.sections_matching(r'remote\.(.*)\.url')
 944
 945 def __remotes_from_dir(dir):
 946     d = os.path.join(basedir.get(), dir)
 947     if os.path.exists(d):
 948         return os.listdir(d)
 949     else:
 950         return []
 951
 952 def remotes_list():
 953     """Return the list of remotes in the repository
 954     """
 955     return (set(__remotes_from_config())
 956             | set(__remotes_from_dir('remotes'))
 957             | set(__remotes_from_dir('branches')))
 958
 959 def remotes_local_branches(remote):
 960     """Returns the list of local branches fetched from given remote
 961     """
 962
 963     branches = []
 964     if remote in __remotes_from_config():
 965         for line in config.getall('remote.%s.fetch' % remote):
 966             branches.append(refspec_localpart(line))
 967     elif remote in __remotes_from_dir('remotes'):
 968         stream = open(os.path.join(basedir.get(), 'remotes', remote), 'r')
 969         for line in stream:
 970             # Only consider Pull lines
 971             m = re.match('^Pull: (.*)\n$', line)
 972             if m:
 973                 branches.append(refspec_localpart(m.group(1)))
 974         stream.close()
 975     elif remote in __remotes_from_dir('branches'):
 976         # old-style branches only declare one branch
 977         branches.append('refs/heads/'+remote);
 978     else:
 979         raise GitException, 'Unknown remote "%s"' % remote
 980
 981     return branches
 982
 983 def identify_remote(branchname):
 984     """Return the name for the remote to pull the given branchname
 985     from, or None if we believe it is a local branch.
 986     """
 987
 988     for remote in remotes_list():
 989         if branchname in remotes_local_branches(remote):
 990             return remote
 991
 992     # if we get here we've found nothing, the branch is a local one
 993     return None
 994
 995 def fetch_head():
 996     """Return the git id for the tip of the parent branch as left by
 997     'git fetch'.
 998     """
 999
1000     fetch_head=None
1001     stream = open(os.path.join(basedir.get(), 'FETCH_HEAD'), "r")
1002     for line in stream:
1003         # Only consider lines not tagged not-for-merge
1004         m = re.match('^([^\t]*)\t\t', line)
1005         if m:
1006             if fetch_head:
1007                 raise GitException, 'StGit does not support multiple FETCH_HEAD'
1008             else:
1009                 fetch_head=m.group(1)
1010     stream.close()
1011
1012     if not fetch_head:
1013         raise GitException, 'No for-merge remote head found in FETCH_HEAD'
1014
1015     # here we are sure to have a single fetch_head
1016     return fetch_head
1017
1018 def all_refs():
1019     """Return a list of all refs in the current repository.
1020     """
1021
1022     return [line.split()[1] for line in GRun('git-show-ref').output_lines()]