text: # Subversion 1.4/1.5 Python API backend
  #
  # Copyright(C) 2007 Daniel Holth et al
  
  import os
  import re
  import sys
  import cPickle as pickle
  import tempfile
  import urllib
  import urllib2
  
  from mercurial import strutil, util, encoding
  from mercurial.i18n import _
  
  # Subversion stuff. Works best with very recent Python SVN bindings
  # e.g. SVN 1.5 or backports. Thanks to the bzr folks for enhancing
  # these bindings.
  
  from cStringIO import StringIO
  
  from common import NoRepo, MissingTool, commit, encodeargs, decodeargs
  from common import commandline, converter_source, converter_sink, mapfile
  
  try:
      from svn.core import SubversionException, Pool
      import svn
      import svn.client
      import svn.core
      import svn.ra
      import svn.delta
      import transport
      import warnings
      warnings.filterwarnings('ignore',
              module='svn.core',
              category=DeprecationWarning)
  
  except ImportError:
      pass
  
  class SvnPathNotFound(Exception):
      pass
  
  def geturl(path):
      try:
          return svn.client.url_from_path(svn.core.svn_path_canonicalize(path))
      except SubversionException:
          pass
      if os.path.isdir(path):
          path = os.path.normpath(os.path.abspath(path))
          if os.name == 'nt':
              path = '/' + util.normpath(path)
          # Module URL is later compared with the repository URL returned
          # by svn API, which is UTF-8.
          path = encoding.tolocal(path)
          return 'file://%s' % urllib.quote(path)
      return path
  
  def optrev(number):
      optrev = svn.core.svn_opt_revision_t()
      optrev.kind = svn.core.svn_opt_revision_number
      optrev.value.number = number
      return optrev
  
  class changedpath(object):
      def __init__(self, p):
          self.copyfrom_path = p.copyfrom_path
          self.copyfrom_rev = p.copyfrom_rev
          self.action = p.action
  
  def get_log_child(fp, url, paths, start, end, limit=0, discover_changed_paths=True,
                      strict_node_history=False):
      protocol = -1
      def receiver(orig_paths, revnum, author, date, message, pool):
          if orig_paths is not None:
              for k, v in orig_paths.iteritems():
                  orig_paths[k] = changedpath(v)
          pickle.dump((orig_paths, revnum, author, date, message),
                      fp, protocol)
  
      try:
          # Use an ra of our own so that our parent can consume
          # our results without confusing the server.
          t = transport.SvnRaTransport(url=url)
          svn.ra.get_log(t.ra, paths, start, end, limit,
                         discover_changed_paths,
                         strict_node_history,
                         receiver)
      except SubversionException, (inst, num):
          pickle.dump(num, fp, protocol)
      except IOError:
          # Caller may interrupt the iteration
          pickle.dump(None, fp, protocol)
      else:
          pickle.dump(None, fp, protocol)
      fp.close()
      # With large history, cleanup process goes crazy and suddenly
      # consumes *huge* amount of memory. The output file being closed,
      # there is no need for clean termination.
      os._exit(0)
  
  def debugsvnlog(ui, **opts):
      """Fetch SVN log in a subprocess and channel them back to parent to
      avoid memory collection issues.
      """
      util.set_binary(sys.stdin)
      util.set_binary(sys.stdout)
      args = decodeargs(sys.stdin.read())
      get_log_child(sys.stdout, *args)
  
  class logstream(object):
      """Interruptible revision log iterator."""
      def __init__(self, stdout):
          self._stdout = stdout
  
      def __iter__(self):
          while True:
              try:
                  entry = pickle.load(self._stdout)
              except EOFError:
                  raise util.Abort(_('Mercurial failed to run itself, check'
                                     ' hg executable is in PATH'))
              try:
                  orig_paths, revnum, author, date, message = entry
              except:
                  if entry is None:
                      break
                  raise SubversionException("child raised exception", entry)
              yield entry
  
      def close(self):
          if self._stdout:
              self._stdout.close()
              self._stdout = None
  
  
  # Check to see if the given path is a local Subversion repo. Verify this by
  # looking for several svn-specific files and directories in the given
  # directory.
  def filecheck(ui, path, proto):
      for x in ('locks', 'hooks', 'format', 'db'):
          if not os.path.exists(os.path.join(path, x)):
              return False
      return True
  
  # Check to see if a given path is the root of an svn repo over http. We verify
  # this by requesting a version-controlled URL we know can't exist and looking
  # for the svn-specific "not found" XML.
  def httpcheck(ui, path, proto):
      try:
          opener = urllib2.build_opener()
          rsp = opener.open('%s://%s/!svn/ver/0/.svn' % (proto, path))
          data = rsp.read()
      except urllib2.HTTPError, inst:
          if inst.code != 404:
              # Except for 404 we cannot know for sure this is not an svn repo
              ui.warn(_('svn: cannot probe remote repository, assume it could '
                        'be a subversion repository. Use --source-type if you '
                        'know better.\n'))
              return True
          data = inst.fp.read()
      except:
          # Could be urllib2.URLError if the URL is invalid or anything else.
          return False
      return '<m:human-readable errcode="160013">' in data
  
  protomap = {'http': httpcheck,
              'https': httpcheck,
              'file': filecheck,
              }
  def issvnurl(ui, url):
      try:
          proto, path = url.split('://', 1)
          if proto == 'file':
              path = urllib.url2pathname(path)
      except ValueError:
          proto = 'file'
          path = os.path.abspath(url)
      if proto == 'file':
          path = path.replace(os.sep, '/')
      check = protomap.get(proto, lambda *args: False)
      while '/' in path:
          if check(ui, path, proto):
              return True
          path = path.rsplit('/', 1)[0]
      return False
  
  # SVN conversion code stolen from bzr-svn and tailor
  #
  # Subversion looks like a versioned filesystem, branches structures
  # are defined by conventions and not enforced by the tool. First,
  # we define the potential branches (modules) as "trunk" and "branches"
  # children directories. Revisions are then identified by their
  # module and revision number (and a repository identifier).
  #
  # The revision graph is really a tree (or a forest). By default, a
  # revision parent is the previous revision in the same module. If the
  # module directory is copied/moved from another module then the
  # revision is the module root and its parent the source revision in
  # the parent module. A revision has at most one parent.
  #
  class svn_source(converter_source):
      def __init__(self, ui, url, rev=None):
          super(svn_source, self).__init__(ui, url, rev=rev)
  
          if not (url.startswith('svn://') or url.startswith('svn+ssh://') or
                  (os.path.exists(url) and
                   os.path.exists(os.path.join(url, '.svn'))) or
                  issvnurl(ui, url)):
              raise NoRepo(_("%s does not look like a Subversion repository")
                           % url)
  
          try:
              SubversionException
          except NameError:
              raise MissingTool(_('Subversion python bindings could not be loaded'))
  
          try:
              version = svn.core.SVN_VER_MAJOR, svn.core.SVN_VER_MINOR
              if version < (1, 4):
                  raise MissingTool(_('Subversion python bindings %d.%d found, '
                                      '1.4 or later required') % version)
          except AttributeError:
              raise MissingTool(_('Subversion python bindings are too old, 1.4 '
                                  'or later required'))
  
          self.lastrevs = {}
  
          latest = None
          try:
              # Support file://path@rev syntax. Useful e.g. to convert
              # deleted branches.
              at = url.rfind('@')
              if at >= 0:
                  latest = int(url[at + 1:])
                  url = url[:at]
          except ValueError:
              pass
          self.url = geturl(url)
          self.encoding = 'UTF-8' # Subversion is always nominal UTF-8
          try:
              self.transport = transport.SvnRaTransport(url=self.url)
              self.ra = self.transport.ra
              self.ctx = self.transport.client
              self.baseurl = svn.ra.get_repos_root(self.ra)
              # Module is either empty or a repository path starting with
              # a slash and not ending with a slash.
              self.module = urllib.unquote(self.url[len(self.baseurl):])
              self.prevmodule = None
              self.rootmodule = self.module
              self.commits = {}
              self.paths = {}
              self.uuid = svn.ra.get_uuid(self.ra)
          except SubversionException:
              ui.traceback()
              raise NoRepo(_("%s does not look like a Subversion repository")
                           % self.url)
  
          if rev:
              try:
                  latest = int(rev)
              except ValueError:
                  raise util.Abort(_('svn: revision %s is not an integer') % rev)
  
          self.startrev = self.ui.config('convert', 'svn.startrev', default=0)
          try:
              self.startrev = int(self.startrev)
              if self.startrev < 0:
                  self.startrev = 0
          except ValueError:
              raise util.Abort(_('svn: start revision %s is not an integer')
                               % self.startrev)
  
          self.head = self.latest(self.module, latest)
          if not self.head:
              raise util.Abort(_('no revision found in module %s')
                               % self.module)
          self.last_changed = self.revnum(self.head)
  
          self._changescache = None
  
          if os.path.exists(os.path.join(url, '.svn/entries')):
              self.wc = url
          else:
              self.wc = None
          self.convertfp = None
  
      def setrevmap(self, revmap):
          lastrevs = {}
          for revid in revmap.iterkeys():
              uuid, module, revnum = self.revsplit(revid)
              lastrevnum = lastrevs.setdefault(module, revnum)
              if revnum > lastrevnum:
                  lastrevs[module] = revnum
          self.lastrevs = lastrevs
  
      def exists(self, path, optrev):
          try:
              svn.client.ls(self.url.rstrip('/') + '/' + urllib.quote(path),
                                   optrev, False, self.ctx)
              return True
          except SubversionException:
              return False
  
      def getheads(self):
  
          def isdir(path, revnum):
              kind = self._checkpath(path, revnum)
              return kind == svn.core.svn_node_dir
  
          def getcfgpath(name, rev):
              cfgpath = self.ui.config('convert', 'svn.' + name)
              if cfgpath is not None and cfgpath.strip() == '':
                  return None
              path = (cfgpath or name).strip('/')
              if not self.exists(path, rev):
                  if cfgpath:
                      raise util.Abort(_('expected %s to be at %r, but not found')
                                   % (name, path))
                  return None
              self.ui.note(_('found %s at %r\n') % (name, path))
              return path
  
          rev = optrev(self.last_changed)
          oldmodule = ''
          trunk = getcfgpath('trunk', rev)
          self.tags = getcfgpath('tags', rev)
          branches = getcfgpath('branches', rev)
  
          # If the project has a trunk or branches, we will extract heads
          # from them. We keep the project root otherwise.
          if trunk:
              oldmodule = self.module or ''
              self.module += '/' + trunk
              self.head = self.latest(self.module, self.last_changed)
              if not self.head:
                  raise util.Abort(_('no revision found in module %s')
                                   % self.module)
  
          # First head in the list is the module's head
          self.heads = [self.head]
          if self.tags is not None:
              self.tags = '%s/%s' % (oldmodule , (self.tags or 'tags'))
  
          # Check if branches bring a few more heads to the list
          if branches:
              rpath = self.url.strip('/')
              branchnames = svn.client.ls(rpath + '/' + urllib.quote(branches),
                                          rev, False, self.ctx)
              for branch in branchnames.keys():
                  module = '%s/%s/%s' % (oldmodule, branches, branch)
                  if not isdir(module, self.last_changed):
                      continue
                  brevid = self.latest(module, self.last_changed)
                  if not brevid:
                      self.ui.note(_('ignoring empty branch %s\n') % branch)
                      continue
                  self.ui.note(_('found branch %s at %d\n') %
                               (branch, self.revnum(brevid)))
                  self.heads.append(brevid)
  
          if self.startrev and self.heads:
              if len(self.heads) > 1:
                  raise util.Abort(_('svn: start revision is not supported '
                                     'with more than one branch'))
              revnum = self.revnum(self.heads[0])
              if revnum < self.startrev:
                  raise util.Abort(
                      _('svn: no revision found after start revision %d')
                                   % self.startrev)
  
          return self.heads
  
      def getfile(self, file, rev):
          data, mode = self._getfile(file, rev)
          self.modecache[(file, rev)] = mode
          return data
  
      def getmode(self, file, rev):
          return self.modecache[(file, rev)]
  
      def getchanges(self, rev):
          if self._changescache and self._changescache[0] == rev:
              return self._changescache[1]
          self._changescache = None
          self.modecache = {}
          (paths, parents) = self.paths[rev]
          if parents:
              files, self.removed, copies = self.expandpaths(rev, paths, parents)
          else:
              # Perform a full checkout on roots
              uuid, module, revnum = self.revsplit(rev)
              entries = svn.client.ls(self.baseurl + urllib.quote(module),
                                      optrev(revnum), True, self.ctx)
              files = [n for n, e in entries.iteritems()
                       if e.kind == svn.core.svn_node_file]
              copies = {}
              self.removed = set()
  
          files.sort()
          files = zip(files, [rev] * len(files))
  
          # caller caches the result, so free it here to release memory
          del self.paths[rev]
          return (files, copies)
  
      def getchangedfiles(self, rev, i):
          changes = self.getchanges(rev)
          self._changescache = (rev, changes)
          return [f[0] for f in changes[0]]
  
      def getcommit(self, rev):
          if rev not in self.commits:
              uuid, module, revnum = self.revsplit(rev)
              self.module = module
              self.reparent(module)
              # We assume that:
              # - requests for revisions after "stop" come from the
              # revision graph backward traversal. Cache all of them
              # down to stop, they will be used eventually.
              # - requests for revisions before "stop" come to get
              # isolated branches parents. Just fetch what is needed.
              stop = self.lastrevs.get(module, 0)
              if revnum < stop:
                  stop = revnum + 1
              self._fetch_revisions(revnum, stop)
          commit = self.commits[rev]
          # caller caches the result, so free it here to release memory
          del self.commits[rev]
          return commit
  
      def gettags(self):
          tags = {}
          if self.tags is None:
              return tags
  
          # svn tags are just a convention, project branches left in a
          # 'tags' directory. There is no other relationship than
          # ancestry, which is expensive to discover and makes them hard
          # to update incrementally.  Worse, past revisions may be
          # referenced by tags far away in the future, requiring a deep
          # history traversal on every calculation.  Current code
          # performs a single backward traversal, tracking moves within
          # the tags directory (tag renaming) and recording a new tag
          # everytime a project is copied from outside the tags
          # directory. It also lists deleted tags, this behaviour may
          # change in the future.
          pendings = []
          tagspath = self.tags
          start = svn.ra.get_latest_revnum(self.ra)
          try:
              for entry in self._getlog([self.tags], start, self.startrev):
                  origpaths, revnum, author, date, message = entry
                  copies = [(e.copyfrom_path, e.copyfrom_rev, p) for p, e
                            in origpaths.iteritems() if e.copyfrom_path]
                  # Apply moves/copies from more specific to general
                  copies.sort(reverse=True)
  
                  srctagspath = tagspath
                  if copies and copies[-1][2] == tagspath:
                      # Track tags directory moves
                      srctagspath = copies.pop()[0]
  
                  for source, sourcerev, dest in copies:
                      if not dest.startswith(tagspath + '/'):
                          continue
                      for tag in pendings:
                          if tag[0].startswith(dest):
                              tagpath = source + tag[0][len(dest):]
                              tag[:2] = [tagpath, sourcerev]
                              break
                      else:
                          pendings.append([source, sourcerev, dest])
  
                  # Filter out tags with children coming from different
                  # parts of the repository like:
                  # /tags/tag.1 (from /trunk:10)
                  # /tags/tag.1/foo (from /branches/foo:12)
                  # Here/tags/tag.1 discarded as well as its children.
                  # It happens with tools like cvs2svn. Such tags cannot
                  # be represented in mercurial.
                  addeds = dict((p, e.copyfrom_path) for p, e
                                in origpaths.iteritems()
                                if e.action == 'A' and e.copyfrom_path)
                  badroots = set()
                  for destroot in addeds:
                      for source, sourcerev, dest in pendings:
                          if (not dest.startswith(destroot + '/')
                              or source.startswith(addeds[destroot] + '/')):
                              continue
                          badroots.add(destroot)
                          break
  
                  for badroot in badroots:
                      pendings = [p for p in pendings if p[2] != badroot
                                  and not p[2].startswith(badroot + '/')]
  
                  # Tell tag renamings from tag creations
                  remainings = []
                  for source, sourcerev, dest in pendings:
                      tagname = dest.split('/')[-1]
                      if source.startswith(srctagspath):
                          remainings.append([source, sourcerev, tagname])
                          continue
                      if tagname in tags:
                          # Keep the latest tag value
                          continue
                      # From revision may be fake, get one with changes
                      try:
                          tagid = self.latest(source, sourcerev)
                          if tagid and tagname not in tags:
                              tags[tagname] = tagid
                      except SvnPathNotFound:
                          # It happens when we are following directories
                          # we assumed were copied with their parents
                          # but were really created in the tag
                          # directory.
                          pass
                  pendings = remainings
                  tagspath = srctagspath
  
          except SubversionException:
              self.ui.note(_('no tags found at revision %d\n') % start)
          return tags
  
      def converted(self, rev, destrev):
          if not self.wc:
              return
          if self.convertfp is None:
              self.convertfp = open(os.path.join(self.wc, '.svn', 'hg-shamap'),
                                    'a')
          self.convertfp.write('%s %d\n' % (destrev, self.revnum(rev)))
          self.convertfp.flush()
  
      def revid(self, revnum, module=None):
          return 'svn:%s%s@%s' % (self.uuid, module or self.module, revnum)
  
      def revnum(self, rev):
          return int(rev.split('@')[-1])
  
      def revsplit(self, rev):
          url, revnum = rev.rsplit('@', 1)
          revnum = int(revnum)
          parts = url.split('/', 1)
          uuid = parts.pop(0)[4:]
          mod = ''
          if parts:
              mod = '/' + parts[0]
          return uuid, mod, revnum
  
      def latest(self, path, stop=0):
          """Find the latest revid affecting path, up to stop. It may return
          a revision in a different module, since a branch may be moved without
          a change being reported. Return None if computed module does not
          belong to rootmodule subtree.
          """
          if not path.startswith(self.rootmodule):
              # Requests on foreign branches may be forbidden at server level
              self.ui.debug('ignoring foreign branch %r\n' % path)
              return None
  
          if not stop:
              stop = svn.ra.get_latest_revnum(self.ra)
          try:
              prevmodule = self.reparent('')
              dirent = svn.ra.stat(self.ra, path.strip('/'), stop)
              self.reparent(prevmodule)
          except SubversionException:
              dirent = None
          if not dirent:
              raise SvnPathNotFound(_('%s not found up to revision %d')
                                    % (path, stop))
  
          # stat() gives us the previous revision on this line of
          # development, but it might be in *another module*. Fetch the
          # log and detect renames down to the latest revision.
          stream = self._getlog([path], stop, dirent.created_rev)
          try:
              for entry in stream:
                  paths, revnum, author, date, message = entry
                  if revnum <= dirent.created_rev:
                      break
  
                  for p in paths:
                      if not path.startswith(p) or not paths[p].copyfrom_path:
                          continue
                      newpath = paths[p].copyfrom_path + path[len(p):]
                      self.ui.debug("branch renamed from %s to %s at %d\n" %
                                    (path, newpath, revnum))
                      path = newpath
                      break
          finally:
              stream.close()
  
          if not path.startswith(self.rootmodule):
              self.ui.debug('ignoring foreign branch %r\n' % path)
              return None
          return self.revid(dirent.created_rev, path)
  
      def reparent(self, module):
          """Reparent the svn transport and return the previous parent."""
          if self.prevmodule == module:
              return module
          svnurl = self.baseurl + urllib.quote(module)
          prevmodule = self.prevmodule
          if prevmodule is None:
              prevmodule = ''
          self.ui.debug("reparent to %s\n" % svnurl)
          svn.ra.reparent(self.ra, svnurl)
          self.prevmodule = module
          return prevmodule
  
      def expandpaths(self, rev, paths, parents):
          changed, removed = set(), set()
          # Map of entrypath, revision for finding source of deleted
          # revisions.
          copyfrom = {}
          copies = {}
  
          new_module, revnum = self.revsplit(rev)[1:]
          if new_module != self.module:
              self.module = new_module
              self.reparent(self.module)
  
          for path, ent in paths:
              entrypath = self.getrelpath(path)
  
              kind = self._checkpath(entrypath, revnum)
              if kind == svn.core.svn_node_file:
                  changed.add(self.recode(entrypath))
                  if not ent.copyfrom_path or not parents:
                      continue
                  # Copy sources not in parent revisions cannot be
                  # represented, ignore their origin for now
                  pmodule, prevnum = self.revsplit(parents[0])[1:]
                  if ent.copyfrom_rev < prevnum:
                      continue
                  copyfrom_path = self.getrelpath(ent.copyfrom_path, pmodule)
                  if not copyfrom_path:
                      continue
                  self.ui.debug("copied to %s from %s@%s\n" %
                                (entrypath, copyfrom_path, ent.copyfrom_rev))
                  copies[self.recode(entrypath)] = self.recode(copyfrom_path)
              elif kind == 0: # gone, but had better be a deleted *file*
                  self.ui.debug("gone from %s\n" % ent.copyfrom_rev)
                  pmodule, prevnum = self.revsplit(parents[0])[1:]
                  parentpath = pmodule + "/" + entrypath
                  fromkind = self._checkpath(entrypath, prevnum, pmodule)
  
                  if fromkind == svn.core.svn_node_file:
                      removed.add(self.recode(entrypath))
                  elif fromkind == svn.core.svn_node_dir:
                      oroot = parentpath.strip('/')
                      nroot = path.strip('/')
                      children = self._find_children(oroot, prevnum)
                      children = [s.replace(oroot, nroot) for s in children]
                      for child in children:
                          childpath = self.getrelpath("/" + child, pmodule)
                          if childpath:
                              removed.add(self.recode(childpath))
                  else:
                      self.ui.debug('unknown path in revision %d: %s\n' % \
                                    (revnum, path))
              elif kind == svn.core.svn_node_dir:                
                  if ent.action == 'M':
                      # If the directory just had a prop change,
                      # then we shouldn't need to look for its children.
                      continue
                  elif ent.action == 'R' and parents:
                      # If a directory is replacing a file, mark the previous
                      # file as deleted
                      pmodule, prevnum = self.revsplit(parents[0])[1:]
                      pkind = self._checkpath(entrypath, prevnum, pmodule)
                      if pkind == svn.core.svn_node_file:
                          removed.add(self.recode(entrypath))
  
                  children = sorted(self._find_children(path, revnum))
                  for child in children:
                      # Can we move a child directory and its
                      # parent in the same commit? (probably can). Could
                      # cause problems if instead of revnum -1,
                      # we have to look in (copyfrom_path, revnum - 1)
                      entrypath = self.getrelpath("/" + child)
                      if entrypath:
                          # Need to filter out directories here...
                          kind = self._checkpath(entrypath, revnum)
                          if kind != svn.core.svn_node_dir:
                              changed.add(self.recode(entrypath))
  
                  # Handle directory copies
                  if not ent.copyfrom_path or not parents:
                      continue
                  # Copy sources not in parent revisions cannot be
                  # represented, ignore their origin for now
                  pmodule, prevnum = self.revsplit(parents[0])[1:]
                  if ent.copyfrom_rev < prevnum:
                      continue
                  copyfrompath = self.getrelpath(ent.copyfrom_path, pmodule)
                  if not copyfrompath:
                      continue
                  copyfrom[path] = ent
                  self.ui.debug("mark %s came from %s:%d\n"
                                % (path, copyfrompath, ent.copyfrom_rev))
                  children = self._find_children(ent.copyfrom_path, ent.copyfrom_rev)
                  children.sort()
                  for child in children:
                      entrypath = self.getrelpath("/" + child, pmodule)
                      if not entrypath:
                          continue
                      copytopath = path + entrypath[len(copyfrompath):]
                      copytopath = self.getrelpath(copytopath)
                      copies[self.recode(copytopath)] = self.recode(entrypath)
  
          changed.update(removed)
          return (list(changed), removed, copies)
  
      def _fetch_revisions(self, from_revnum, to_revnum):
          if from_revnum < to_revnum:
              from_revnum, to_revnum = to_revnum, from_revnum
  
          self.child_cset = None
  
          def parselogentry(orig_paths, revnum, author, date, message):
              """Return the parsed commit object or None, and True if
              the revision is a branch root.
              """
              self.ui.debug("parsing revision %d (%d changes)\n" %
                            (revnum, len(orig_paths)))
  
              branched = False
              rev = self.revid(revnum)
              # branch log might return entries for a parent we already have
  
              if rev in self.commits or revnum < to_revnum:
                  return None, branched
  
              parents = []
              # check whether this revision is the start of a branch or part
              # of a branch renaming
              orig_paths = sorted(orig_paths.iteritems())
              root_paths = [(p, e) for p, e in orig_paths
                            if self.module.startswith(p)]
              if root_paths:
                  path, ent = root_paths[-1]
                  if ent.copyfrom_path:
                      branched = True
                      newpath = ent.copyfrom_path + self.module[len(path):]
                      # ent.copyfrom_rev may not be the actual last revision
                      previd = self.latest(newpath, ent.copyfrom_rev)
                      if previd is not None:
                          prevmodule, prevnum = self.revsplit(previd)[1:]
                          if prevnum >= self.startrev:
                              parents = [previd]
                              self.ui.note(
                                  _('found parent of branch %s at %d: %s\n') %
                                  (self.module, prevnum, prevmodule))
                  else:
                      self.ui.debug("no copyfrom path, don't know what to do.\n")
  
              paths = []
              # filter out unrelated paths
              for path, ent in orig_paths:
                  if self.getrelpath(path) is None:
                      continue
                  paths.append((path, ent))
  
              # Example SVN datetime. Includes microseconds.
              # ISO-8601 conformant
              # '2007-01-04T17:35:00.902377Z'
              date = util.parsedate(date[:19] + " UTC", ["%Y-%m-%dT%H:%M:%S"])
  
              log = message and self.recode(message) or ''
              author = author and self.recode(author) or ''
              try:
                  branch = self.module.split("/")[-1]
                  if branch == 'trunk':
                      branch = ''
              except IndexError:
                  branch = None
  
              cset = commit(author=author,
                            date=util.datestr(date),
                            desc=log,
                            parents=parents,
                            branch=branch,
                            rev=rev)
  
              self.commits[rev] = cset
              # The parents list is *shared* among self.paths and the
              # commit object. Both will be updated below.
              self.paths[rev] = (paths, cset.parents)
              if self.child_cset and not self.child_cset.parents:
                  self.child_cset.parents[:] = [rev]
              self.child_cset = cset
              return cset, branched
  
          self.ui.note(_('fetching revision log for "%s" from %d to %d\n') %
                       (self.module, from_revnum, to_revnum))
  
          try:
              firstcset = None
              lastonbranch = False
              stream = self._getlog([self.module], from_revnum, to_revnum)
              try:
                  for entry in stream:
                      paths, revnum, author, date, message = entry
                      if revnum < self.startrev:
                          lastonbranch = True
                          break
                      if not paths:
                          self.ui.debug('revision %d has no entries\n' % revnum)
                          # If we ever leave the loop on an empty
                          # revision, do not try to get a parent branch
                          lastonbranch = lastonbranch or revnum == 0
                          continue
                      cset, lastonbranch = parselogentry(paths, revnum, author,
                                                         date, message)
                      if cset:
                          firstcset = cset
                      if lastonbranch:
                          break
              finally:
                  stream.close()
  
              if not lastonbranch and firstcset and not firstcset.parents:
                  # The first revision of the sequence (the last fetched one)
                  # has invalid parents if not a branch root. Find the parent
                  # revision now, if any.
                  try:
                      firstrevnum = self.revnum(firstcset.rev)
                      if firstrevnum > 1:
                          latest = self.latest(self.module, firstrevnum - 1)
                          if latest:
                              firstcset.parents.append(latest)
                  except SvnPathNotFound:
                      pass
          except SubversionException, (inst, num):
              if num == svn.core.SVN_ERR_FS_NO_SUCH_REVISION:
                  raise util.Abort(_('svn: branch has no revision %s') % to_revnum)
              raise
  
      def _getfile(self, file, rev):
          # TODO: ra.get_file transmits the whole file instead of diffs.
          if file in self.removed:
              raise IOError()
          mode = ''
          try:
              new_module, revnum = self.revsplit(rev)[1:]
              if self.module != new_module:
                  self.module = new_module
                  self.reparent(self.module)
              io = StringIO()
              info = svn.ra.get_file(self.ra, file, revnum, io)
              data = io.getvalue()
              # ra.get_files() seems to keep a reference on the input buffer
              # preventing collection. Release it explicitely.
              io.close()
              if isinstance(info, list):
                  info = info[-1]
              mode = ("svn:executable" in info) and 'x' or ''
              mode = ("svn:special" in info) and 'l' or mode
          except SubversionException, e:
              notfound = (svn.core.SVN_ERR_FS_NOT_FOUND,
                  svn.core.SVN_ERR_RA_DAV_PATH_NOT_FOUND)
              if e.apr_err in notfound: # File not found
                  raise IOError()
              raise
          if mode == 'l':
              link_prefix = "link "
              if data.startswith(link_prefix):
                  data = data[len(link_prefix):]
          return data, mode
  
      def _find_children(self, path, revnum):
          path = path.strip('/')
          pool = Pool()
          rpath = '/'.join([self.baseurl, urllib.quote(path)]).strip('/')
          return ['%s/%s' % (path, x) for x in
                  svn.client.ls(rpath, optrev(revnum), True, self.ctx, pool).keys()]
  
      def getrelpath(self, path, module=None):
          if module is None:
              module = self.module
          # Given the repository url of this wc, say
          #   "http://server/plone/CMFPlone/branches/Plone-2_0-branch"
          # extract the "entry" portion (a relative path) from what
          # svn log --xml says, ie
          #   "/CMFPlone/branches/Plone-2_0-branch/tests/PloneTestCase.py"
          # that is to say "tests/PloneTestCase.py"
          if path.startswith(module):
              relative = path.rstrip('/')[len(module):]
              if relative.startswith('/'):
                  return relative[1:]
              elif relative == '':
                  return relative
  
          # The path is outside our tracked tree...
          self.ui.debug('%r is not under %r, ignoring\n' % (path, module))
          return None
  
      def _checkpath(self, path, revnum, module=None):
          if module is not None:
              prevmodule = self.reparent('')
              path = module + '/' + path
          try:
              # ra.check_path does not like leading slashes very much, it leads
              # to PROPFIND subversion errors
              return svn.ra.check_path(self.ra, path.strip('/'), revnum)
          finally:
              if module is not None:
                  self.reparent(prevmodule)
      
      def _getlog(self, paths, start, end, limit=0, discover_changed_paths=True,
                  strict_node_history=False):
          # Normalize path names, svn >= 1.5 only wants paths relative to
          # supplied URL
          relpaths = []
          for p in paths:
              if not p.startswith('/'):
                  p = self.module + '/' + p
              relpaths.append(p.strip('/'))
          args = [self.baseurl, relpaths, start, end, limit, discover_changed_paths,
                  strict_node_history]
          arg = encodeargs(args)
          hgexe = util.hgexecutable()
          cmd = '%s debugsvnlog' % util.shellquote(hgexe)
          stdin, stdout = util.popen2(cmd)
          stdin.write(arg)
          try:
              stdin.close()
          except IOError:
              raise util.Abort(_('Mercurial failed to run itself, check'
                                 ' hg executable is in PATH'))
          return logstream(stdout)
  
  pre_revprop_change = '''#!/bin/sh
  
  REPOS="$1"
  REV="$2"
  USER="$3"
  PROPNAME="$4"
  ACTION="$5"
  
  if [ "$ACTION" = "M" -a "$PROPNAME" = "svn:log" ]; then exit 0; fi
  if [ "$ACTION" = "A" -a "$PROPNAME" = "hg:convert-branch" ]; then exit 0; fi
  if [ "$ACTION" = "A" -a "$PROPNAME" = "hg:convert-rev" ]; then exit 0; fi
  
  echo "Changing prohibited revision property" >&2
  exit 1
  '''
  
  class svn_sink(converter_sink, commandline):
      commit_re = re.compile(r'Committed revision (\d+).', re.M)
  
      def prerun(self):
          if self.wc:
              os.chdir(self.wc)
  
      def postrun(self):
          if self.wc:
              os.chdir(self.cwd)
  
      def join(self, name):
          return os.path.join(self.wc, '.svn', name)
  
      def revmapfile(self):
          return self.join('hg-shamap')
  
      def authorfile(self):
          return self.join('hg-authormap')
  
      def __init__(self, ui, path):
          converter_sink.__init__(self, ui, path)
          commandline.__init__(self, ui, 'svn')
          self.delete = []
          self.setexec = []
          self.delexec = []
          self.copies = []
          self.wc = None
          self.cwd = os.getcwd()
  
          path = os.path.realpath(path)
  
          created = False
          if os.path.isfile(os.path.join(path, '.svn', 'entries')):
              self.wc = path
              self.run0('update')
          else:
              wcpath = os.path.join(os.getcwd(), os.path.basename(path) + '-wc')
  
              if os.path.isdir(os.path.dirname(path)):
                  if not os.path.exists(os.path.join(path, 'db', 'fs-type')):
                      ui.status(_('initializing svn repository %r\n') %
                                os.path.basename(path))
                      commandline(ui, 'svnadmin').run0('create', path)
                      created = path
                  path = util.normpath(path)
                  if not path.startswith('/'):
                      path = '/' + path
                  path = 'file://' + path
  
              ui.status(_('initializing svn working copy %r\n')
                        % os.path.basename(wcpath))
              self.run0('checkout', path, wcpath)
  
              self.wc = wcpath
          self.opener = util.opener(self.wc)
          self.wopener = util.opener(self.wc)
          self.childmap = mapfile(ui, self.join('hg-childmap'))
          self.is_exec = util.checkexec(self.wc) and util.is_exec or None
  
          if created:
              hook = os.path.join(created, 'hooks', 'pre-revprop-change')
              fp = open(hook, 'w')
              fp.write(pre_revprop_change)
              fp.close()
              util.set_flags(hook, False, True)
  
          xport = transport.SvnRaTransport(url=geturl(path))
          self.uuid = svn.ra.get_uuid(xport.ra)
  
      def wjoin(self, *names):
          return os.path.join(self.wc, *names)
  
      def putfile(self, filename, flags, data):
          if 'l' in flags:
              self.wopener.symlink(data, filename)
          else:
              try:
                  if os.path.islink(self.wjoin(filename)):
                      os.unlink(filename)
              except OSError:
                  pass
              self.wopener(filename, 'w').write(data)
  
              if self.is_exec:
                  was_exec = self.is_exec(self.wjoin(filename))
              else:
                  # On filesystems not supporting execute-bit, there is no way
                  # to know if it is set but asking subversion. Setting it
                  # systematically is just as expensive and much simpler.
                  was_exec = 'x' not in flags
  
              util.set_flags(self.wjoin(filename), False, 'x' in flags)
              if was_exec:
                  if 'x' not in flags:
                      self.delexec.append(filename)
              else:
                  if 'x' in flags:
                      self.setexec.append(filename)
  
      def _copyfile(self, source, dest):
          # SVN's copy command pukes if the destination file exists, but
          # our copyfile method expects to record a copy that has
          # already occurred.  Cross the semantic gap.
          wdest = self.wjoin(dest)
          exists = os.path.exists(wdest)
          if exists:
              fd, tempname = tempfile.mkstemp(
                  prefix='hg-copy-', dir=os.path.dirname(wdest))
              os.close(fd)
              os.unlink(tempname)
              os.rename(wdest, tempname)
          try:
              self.run0('copy', source, dest)
          finally:
              if exists:
                  try:
                      os.unlink(wdest)
                  except OSError:
                      pass
                  os.rename(tempname, wdest)
  
      def dirs_of(self, files):
          dirs = set()
          for f in files:
              if os.path.isdir(self.wjoin(f)):
                  dirs.add(f)
              for i in strutil.rfindall(f, '/'):
                  dirs.add(f[:i])
          return dirs
  
      def add_dirs(self, files):
          add_dirs = [d for d in sorted(self.dirs_of(files))
                      if not os.path.exists(self.wjoin(d, '.svn', 'entries'))]
          if add_dirs:
              self.xargs(add_dirs, 'add', non_recursive=True, quiet=True)
          return add_dirs
  
      def add_files(self, files):
          if files:
              self.xargs(files, 'add', quiet=True)
          return files
  
      def tidy_dirs(self, names):
          deleted = []
          for d in sorted(self.dirs_of(names), reverse=True):
              wd = self.wjoin(d)
              if os.listdir(wd) == '.svn':
                  self.run0('delete', d)
                  deleted.append(d)
          return deleted
  
      def addchild(self, parent, child):
          self.childmap[parent] = child
  
      def revid(self, rev):
          return u"svn:%s@%s" % (self.uuid, rev)
  
      def putcommit(self, files, copies, parents, commit, source, revmap):
          # Apply changes to working copy
          for f, v in files:
              try:
                  data = source.getfile(f, v)
              except IOError:
                  self.delete.append(f)
              else:
                  e = source.getmode(f, v)
                  self.putfile(f, e, data)
                  if f in copies:
                      self.copies.append([copies[f], f])
          files = [f[0] for f in files]
  
          for parent in parents:
              try:
                  return self.revid(self.childmap[parent])
              except KeyError:
                  pass
          entries = set(self.delete)
          files = frozenset(files)
          entries.update(self.add_dirs(files.difference(entries)))
          if self.copies:
              for s, d in self.copies:
                  self._copyfile(s, d)
              self.copies = []
          if self.delete:
              self.xargs(self.delete, 'delete')
              self.delete = []
          entries.update(self.add_files(files.difference(entries)))
          entries.update(self.tidy_dirs(entries))
          if self.delexec:
              self.xargs(self.delexec, 'propdel', 'svn:executable')
              self.delexec = []
          if self.setexec:
              self.xargs(self.setexec, 'propset', 'svn:executable', '*')
              self.setexec = []
  
          fd, messagefile = tempfile.mkstemp(prefix='hg-convert-')
          fp = os.fdopen(fd, 'w')
          fp.write(commit.desc)
          fp.close()
          try:
              output = self.run0('commit',
                                 username=util.shortuser(commit.author),
                                 file=messagefile,
                                 encoding='utf-8')
              try:
                  rev = self.commit_re.search(output).group(1)
              except AttributeError:
                  if not files:
                      return parents[0]
                  self.ui.warn(_('unexpected svn output:\n'))
                  self.ui.warn(output)
                  raise util.Abort(_('unable to cope with svn output'))
              if commit.rev:
                  self.run('propset', 'hg:convert-rev', commit.rev,
                           revprop=True, revision=rev)
              if commit.branch and commit.branch != 'default':
                  self.run('propset', 'hg:convert-branch', commit.branch,
                           revprop=True, revision=rev)
              for parent in parents:
                  self.addchild(parent, rev)
              return self.revid(rev)
          finally:
              os.unlink(messagefile)
  
      def puttags(self, tags):
          self.ui.warn(_('XXX TAGS NOT IMPLEMENTED YET\n'))
  