Merge branch 'submodule'

11 files changed, 1245 insertions, 37 deletions

diff --git a/lib/git/objects/__init__.py b/lib/git/objects/__init__.py
index 85c7e38c..e8e0ef39 100644
--- a/lib/git/objects/__init__.py
+++ b/lib/git/objects/__init__.py
@@ -3,11 +3,18 @@ Import all submodules main classes into the package space
 """
 import inspect
 from base import *
+# Fix import dependency - add IndexObject to the util module, so that it can be 
+# imported by the submodule.base
+import submodule.util
+submodule.util.IndexObject = IndexObject
+from submodule.base import *
+from submodule.root import *
+
+# must come after submodule was made available
 from tag import *
 from blob import *
-from tree import *
 from commit import *
-from submodule import *
+from tree import *
 from util import Actor
 
 __all__ = [ name for name, obj in locals().items()
diff --git a/lib/git/objects/base.py b/lib/git/objects/base.py
index 41862ac2..b8cec47f 100644
--- a/lib/git/objects/base.py
+++ b/lib/git/objects/base.py
@@ -62,17 +62,6 @@ class Object(LazyMixin):
 		inst.size = oinfo.size
 		return inst 
 	
-	def _set_self_from_args_(self, args_dict):
-		"""Initialize attributes on self from the given dict that was retrieved
-		from locals() in the calling method.
-		
-		Will only set an attribute on self if the corresponding value in args_dict
-		is not None"""
-		for attr, val in args_dict.items():
-			if attr != "self" and val is not None:
-				setattr( self, attr, val )
-		# END set all non-None attributes
-	
 	def _set_cache_(self, attr):
 		"""Retrieve object information"""
 		if attr	 == "size":
@@ -125,7 +114,10 @@ class Object(LazyMixin):
 class IndexObject(Object):
 	"""Base for all objects that can be part of the index file , namely Tree, Blob and
 	SubModule objects"""
-	__slots__ = ("path", "mode") 
+	__slots__ = ("path", "mode")
+	
+	# for compatability with iterable lists
+	_id_attribute_ = 'path'
 	
 	def __init__(self, repo, binsha, mode=None, path=None):
 		"""Initialize a newly instanced IndexObject
@@ -140,7 +132,10 @@ class IndexObject(Object):
 			Path may not be set of the index object has been created directly as it cannot
 			be retrieved without knowing the parent tree."""
 		super(IndexObject, self).__init__(repo, binsha)
-		self._set_self_from_args_(locals())
+		if mode is not None:
+			self.mode = mode
+		if path is not None:
+			self.path = path
 	
 	def __hash__(self):
 		""":return:
diff --git a/lib/git/objects/commit.py b/lib/git/objects/commit.py
index 58c82da2..a2b6c554 100644
--- a/lib/git/objects/commit.py
+++ b/lib/git/objects/commit.py
@@ -108,7 +108,26 @@ class Commit(base.Object, Iterable, Diffable, Traversable, Serializable):
 		super(Commit,self).__init__(repo, binsha)
 		if tree is not None:
 			assert isinstance(tree, Tree), "Tree needs to be a Tree instance, was %s" % type(tree)
-		self._set_self_from_args_(locals())
+		if tree is not None:
+			self.tree = tree
+		if author is not None:
+			self.author = author
+		if authored_date is not None:
+			self.authored_date = authored_date
+		if author_tz_offset is not None:
+			self.author_tz_offset = author_tz_offset
+		if committer is not None:
+			self.committer = committer
+		if committed_date is not None:
+			self.committed_date = committed_date
+		if committer_tz_offset is not None:
+			self.committer_tz_offset = committer_tz_offset
+		if message is not None:
+			self.message = message
+		if parents is not None:
+			self.parents = parents
+		if encoding is not None:
+			self.encoding = encoding
 		
 	@classmethod
 	def _get_intermediate_items(cls, commit):
@@ -346,6 +365,9 @@ class Commit(base.Object, Iterable, Diffable, Traversable, Serializable):
 		new_commit.binsha = istream.binsha
 		
 		if head:
+			# need late import here, importing git at the very beginning throws
+			# as well ... 
+			import git.refs
 			try:
 				repo.head.commit = new_commit
 			except ValueError:
@@ -434,7 +456,7 @@ class Commit(base.Object, Iterable, Diffable, Traversable, Serializable):
 		try:
 			self.author.name = self.author.name.decode(self.encoding) 
 		except UnicodeDecodeError:
-			print >> sys.stderr, "Failed to decode author name: %s" % self.author.name
+			print >> sys.stderr, "Failed to decode author name '%s' using encoding %s" % (self.author.name, self.encoding)
 		# END handle author's encoding
 		
 		# a stream from our data simply gives us the plain message
@@ -443,7 +465,7 @@ class Commit(base.Object, Iterable, Diffable, Traversable, Serializable):
 		try:
 			self.message = self.message.decode(self.encoding)
 		except UnicodeDecodeError:
-			print >> sys.stderr, "Failed to decode message: %s" % self.message
+			print >> sys.stderr, "Failed to decode message '%s' using encoding %s" % (self.message, self.encoding)
 		# END exception handling 
 		return self
 		
diff --git a/lib/git/objects/submodule.py b/lib/git/objects/submodule.py
deleted file mode 100644
index 1f571a48..00000000
--- a/lib/git/objects/submodule.py
+++ /dev/null
@@ -1,16 +0,0 @@
-import base
-
-__all__ = ("Submodule", )
-
-class Submodule(base.IndexObject):
-	"""Implements access to a git submodule. They are special in that their sha
-	represents a commit in the submodule's repository which is to be checked out
-	at the path of this instance. 
-	The submodule type does not have a string type associated with it, as it exists
-	solely as a marker in the tree and index"""
-	
-	# this is a bogus type for base class compatability
-	type = 'submodule'
-	
-	# TODO: Add functions to retrieve a repo for the submodule, to allow 
-	# its initiailization and handling
diff --git a/lib/git/objects/submodule/__init__.py b/lib/git/objects/submodule/__init__.py
new file mode 100644
index 00000000..8b137891
--- /dev/null
+++ b/lib/git/objects/submodule/__init__.py
@@ -0,0 +1 @@
+
diff --git a/lib/git/objects/submodule/base.py b/lib/git/objects/submodule/base.py
new file mode 100644
index 00000000..347af58e
--- /dev/null
+++ b/lib/git/objects/submodule/base.py
@@ -0,0 +1,816 @@
+import util
+from util import (
+					mkhead,
+					sm_name, 
+					sm_section, 
+					unbare_repo, 
+					SubmoduleConfigParser,
+					find_first_remote_branch
+				)
+from git.objects.util import Traversable
+from StringIO import StringIO					# need a dict to set bloody .name field
+from git.util import (
+						Iterable, 
+						join_path_native, 
+						to_native_path_linux
+					)
+from git.config import SectionConstraint
+from git.exc import (
+					InvalidGitRepositoryError, 
+					NoSuchPathError
+					)
+import stat
+import git
+
+import os
+import sys
+
+import shutil
+
+__all__ = ["Submodule"]
+
+
+# IndexObject comes via util module, its a 'hacky' fix thanks to pythons import 
+# mechanism which cause plenty of trouble of the only reason for packages and
+# modules is refactoring - subpackages shoudn't depend on parent packages
+class Submodule(util.IndexObject, Iterable, Traversable):
+	"""Implements access to a git submodule. They are special in that their sha
+	represents a commit in the submodule's repository which is to be checked out
+	at the path of this instance. 
+	The submodule type does not have a string type associated with it, as it exists
+	solely as a marker in the tree and index.
+	
+	All methods work in bare and non-bare repositories."""
+	
+	_id_attribute_ = "name"
+	k_modules_file = '.gitmodules'
+	k_head_option = 'branch'
+	k_head_default = 'master'
+	k_default_mode = stat.S_IFDIR | stat.S_IFLNK		# submodules are directories with link-status
+	
+	# this is a bogus type for base class compatability
+	type = 'submodule'
+	
+	__slots__ = ('_parent_commit', '_url', '_branch', '_name', '__weakref__')
+	_cache_attrs = ('path', '_url', '_branch')
+	
+	def __init__(self, repo, binsha, mode=None, path=None, name = None, parent_commit=None, url=None, branch=None):
+		"""Initialize this instance with its attributes. We only document the ones 
+		that differ from ``IndexObject``
+		
+		:param repo: Our parent repository
+		:param binsha: binary sha referring to a commit in the remote repository, see url parameter
+		:param parent_commit: see set_parent_commit()
+		:param url: The url to the remote repository which is the submodule
+		:param branch: Head instance to checkout when cloning the remote repository"""
+		super(Submodule, self).__init__(repo, binsha, mode, path)
+		self.size = 0
+		if parent_commit is not None:
+			self._parent_commit = parent_commit
+		if url is not None:
+			self._url = url
+		if branch is not None:
+			assert isinstance(branch, git.Head)
+			self._branch = branch
+		if name is not None:
+			self._name = name
+	
+	def _set_cache_(self, attr):
+		if attr == '_parent_commit':
+			# set a default value, which is the root tree of the current head
+			self._parent_commit = self.repo.commit()
+		elif attr in ('path', '_url', '_branch'):
+			reader = self.config_reader()
+			# default submodule values
+			self.path = reader.get_value('path')
+			self._url = reader.get_value('url')
+			# git-python extension values - optional
+			self._branch = mkhead(self.repo, reader.get_value(self.k_head_option, self.k_head_default))
+		elif attr == '_name':
+			raise AttributeError("Cannot retrieve the name of a submodule if it was not set initially")
+		else:
+			super(Submodule, self)._set_cache_(attr)
+		# END handle attribute name
+		
+	def _get_intermediate_items(self, item):
+		""":return: all the submodules of our module repository"""
+		try:
+			return type(self).list_items(item.module())
+		except InvalidGitRepositoryError:
+			return list()
+		# END handle intermeditate items
+		
+	def __eq__(self, other):
+		"""Compare with another submodule"""
+		# we may only compare by name as this should be the ID they are hashed with
+		# Otherwise this type wouldn't be hashable
+		# return self.path == other.path and self.url == other.url and super(Submodule, self).__eq__(other)
+		return self._name == other._name
+		
+	def __ne__(self, other):
+		"""Compare with another submodule for inequality"""
+		return not (self == other)
+		
+	def __hash__(self):
+		"""Hash this instance using its logical id, not the sha"""
+		return hash(self._name)
+		
+	def __str__(self):
+		return self._name
+		
+	def __repr__(self):
+		return "git.%s(name=%s, path=%s, url=%s, branch=%s)" % (type(self).__name__, self._name, self.path, self.url, self.branch) 
+		
+	@classmethod
+	def _config_parser(cls, repo, parent_commit, read_only):
+		""":return: Config Parser constrained to our submodule in read or write mode
+		:raise IOError: If the .gitmodules file cannot be found, either locally or in the repository
+			at the given parent commit. Otherwise the exception would be delayed until the first 
+			access of the config parser"""
+		parent_matches_head = repo.head.commit == parent_commit
+		if not repo.bare and parent_matches_head:
+			fp_module = cls.k_modules_file
+			fp_module_path = os.path.join(repo.working_tree_dir, fp_module)
+			if not os.path.isfile(fp_module_path):
+				raise IOError("%s file was not accessible" % fp_module_path)
+			# END handle existance
+			fp_module = fp_module_path
+		else:
+			try:
+				fp_module = cls._sio_modules(parent_commit)
+			except KeyError:
+				raise IOError("Could not find %s file in the tree of parent commit %s" % (cls.k_modules_file, parent_commit))
+			# END handle exceptions
+		# END handle non-bare working tree
+		
+		if not read_only and (repo.bare or not parent_matches_head):
+			raise ValueError("Cannot write blobs of 'historical' submodule configurations")
+		# END handle writes of historical submodules
+		
+		return SubmoduleConfigParser(fp_module, read_only = read_only)
+
+	def _clear_cache(self):
+		# clear the possibly changed values
+		for name in self._cache_attrs:
+			try:
+				delattr(self, name)
+			except AttributeError:
+				pass
+			# END try attr deletion
+		# END for each name to delete
+		
+	@classmethod
+	def _sio_modules(cls, parent_commit):
+		""":return: Configuration file as StringIO - we only access it through the respective blob's data"""
+		sio = StringIO(parent_commit.tree[cls.k_modules_file].data_stream.read())
+		sio.name = cls.k_modules_file
+		return sio
+	
+	def _config_parser_constrained(self, read_only):
+		""":return: Config Parser constrained to our submodule in read or write mode"""
+		parser = self._config_parser(self.repo, self._parent_commit, read_only)
+		parser.set_submodule(self)
+		return SectionConstraint(parser, sm_section(self.name))
+		
+	#{ Edit Interface
+	
+	@classmethod
+	def add(cls, repo, name, path, url=None, branch=None, no_checkout=False):
+		"""Add a new submodule to the given repository. This will alter the index
+		as well as the .gitmodules file, but will not create a new commit.
+		If the submodule already exists, no matter if the configuration differs
+		from the one provided, the existing submodule will be returned.
+		
+		:param repo: Repository instance which should receive the submodule
+		:param name: The name/identifier for the submodule
+		:param path: repository-relative or absolute path at which the submodule 
+			should be located
+			It will be created as required during the repository initialization.
+		:param url: git-clone compatible URL, see git-clone reference for more information
+			If None, the repository is assumed to exist, and the url of the first
+			remote is taken instead. This is useful if you want to make an existing
+			repository a submodule of anotherone.
+		:param branch: branch at which the submodule should (later) be checked out.
+			The given branch must exist in the remote repository, and will be checked
+			out locally as a tracking branch.
+			It will only be written into the configuration if it not None, which is
+			when the checked out branch will be the one the remote HEAD pointed to.
+			The result you get in these situation is somewhat fuzzy, and it is recommended
+			to specify at least 'master' here
+		:param no_checkout: if True, and if the repository has to be cloned manually, 
+			no checkout will be performed
+		:return: The newly created submodule instance
+		:note: works atomically, such that no change will be done if the repository
+			update fails for instance"""
+		if repo.bare:
+			raise InvalidGitRepositoryError("Cannot add submodules to bare repositories")
+		# END handle bare repos
+		
+		path = to_native_path_linux(path)
+		if path.endswith('/'):
+			path = path[:-1]
+		# END handle trailing slash
+		
+		# INSTANTIATE INTERMEDIATE SM
+		sm = cls(repo, cls.NULL_BIN_SHA, cls.k_default_mode, path, name)
+		if sm.exists():
+			# reretrieve submodule from tree
+			return repo.head.commit.tree[path]
+		# END handle existing
+		
+		br = mkhead(repo, branch or cls.k_head_default)
+		has_module = sm.module_exists()
+		branch_is_default = branch is None
+		if has_module and url is not None:
+			if url not in [r.url for r in sm.module().remotes]:
+				raise ValueError("Specified URL '%s' does not match any remote url of the repository at '%s'" % (url, sm.abspath))
+			# END check url
+		# END verify urls match
+		
+		mrepo = None
+		if url is None:
+			if not has_module:
+				raise ValueError("A URL was not given and existing repository did not exsit at %s" % path)
+			# END check url
+			mrepo = sm.module()
+			urls = [r.url for r in mrepo.remotes]
+			if not urls:
+				raise ValueError("Didn't find any remote url in repository at %s" % sm.abspath)
+			# END verify we have url
+			url = urls[0]
+		else:
+			# clone new repo
+			kwargs = {'n' : no_checkout}
+			if not branch_is_default:
+				kwargs['b'] = str(br)
+			# END setup checkout-branch
+			mrepo = git.Repo.clone_from(url, path, **kwargs)
+		# END verify url
+		
+		# update configuration and index
+		index = sm.repo.index
+		writer = sm.config_writer(index=index, write=False)
+		writer.set_value('url', url)
+		writer.set_value('path', path)
+		
+		sm._url = url
+		if not branch_is_default:
+			# store full path
+			writer.set_value(cls.k_head_option, br.path)
+			sm._branch = br.path
+		# END handle path
+		del(writer)
+		
+		# NOTE: Have to write the repo config file as well, otherwise
+		# the default implementation will be offended and not update the repository
+		# Maybe this is a good way to assure it doesn't get into our way, but 
+		# we want to stay backwards compatible too ... . Its so redundant !
+		repo.config_writer().set_value(sm_section(sm.name), 'url', url)
+		
+		# we deliberatly assume that our head matches our index !
+		pcommit = repo.head.commit
+		sm._parent_commit = pcommit
+		sm.binsha = mrepo.head.commit.binsha
+		index.add([sm], write=True)
+		
+		return sm
+		
+	def update(self, recursive=False, init=True, to_latest_revision=False):
+		"""Update the repository of this submodule to point to the checkout
+		we point at with the binsha of this instance.
+		
+		:param recursive: if True, we will operate recursively and update child-
+			modules as well.
+		:param init: if True, the module repository will be cloned into place if necessary
+		:param to_latest_revision: if True, the submodule's sha will be ignored during checkout.
+			Instead, the remote will be fetched, and the local tracking branch updated.
+			This only works if we have a local tracking branch, which is the case
+			if the remote repository had a master branch, or of the 'branch' option 
+			was specified for this submodule and the branch existed remotely
+		:note: does nothing in bare repositories
+		:note: method is definitely not atomic if recurisve is True
+		:return: self"""
+		if self.repo.bare:
+			return self
+		#END pass in bare mode
+		
+		
+		# ASSURE REPO IS PRESENT AND UPTODATE
+		#####################################
+		try:
+			mrepo = self.module()
+			for remote in mrepo.remotes:
+				remote.fetch()
+			#END fetch new data
+		except InvalidGitRepositoryError:
+			if not init:
+				return self
+			# END early abort if init is not allowed
+			import git
+			
+			# there is no git-repository yet - but delete empty paths
+			module_path = join_path_native(self.repo.working_tree_dir, self.path)
+			if os.path.isdir(module_path):
+				try:
+					os.rmdir(module_path)
+				except OSError:
+					raise OSError("Module directory at %r does already exist and is non-empty" % module_path)
+				# END handle OSError
+			# END handle directory removal
+			
+			# don't check it out at first - nonetheless it will create a local
+			# branch according to the remote-HEAD if possible
+			mrepo = git.Repo.clone_from(self.url, module_path, n=True)
+			
+			# see whether we have a valid branch to checkout
+			try:
+				# find  a remote which has our branch - we try to be flexible
+				remote_branch = find_first_remote_branch(mrepo.remotes, self.branch)
+				local_branch = self.branch
+				if not local_branch.is_valid():
+					# Setup a tracking configuration - branch doesn't need to 
+					# exist to do that
+					local_branch.set_tracking_branch(remote_branch)
+				#END handle local branch
+				
+				# have a valid branch, but no checkout - make sure we can figure
+				# that out by marking the commit with a null_sha
+				# have to write it directly as .commit = NULLSHA tries to resolve the sha
+				# This will bring the branch into existance
+				refpath = join_path_native(mrepo.git_dir, local_branch.path)
+				refdir = os.path.dirname(refpath)
+				if not os.path.isdir(refdir):
+					os.makedirs(refdir)
+				#END handle directory
+				open(refpath, 'w').write(self.NULL_HEX_SHA)
+				# END initial checkout + branch creation
+				
+				# make sure HEAD is not detached
+				mrepo.head.ref = local_branch
+			except IndexError:
+				print >> sys.stderr, "Warning: Failed to checkout tracking branch %s" % self.branch 
+			#END handle tracking branch
+		#END handle initalization
+		
+		
+		# DETERMINE SHAS TO CHECKOUT
+		############################
+		binsha = self.binsha
+		hexsha = self.hexsha
+		is_detached = mrepo.head.is_detached
+		if to_latest_revision:
+			msg_base = "Cannot update to latest revision in repository at %r as " % mrepo.working_dir
+			if not is_detached:
+				rref = mrepo.head.ref.tracking_branch()
+				if rref is not None:
+					rcommit = rref.commit
+					binsha = rcommit.binsha
+					hexsha = rcommit.hexsha
+				else:
+					print >> sys.stderr, "%s a tracking branch was not set for local branch '%s'" % (msg_base, mrepo.head.ref) 
+				# END handle remote ref
+			else:
+				print >> sys.stderr, "%s there was no local tracking branch" % msg_base
+			# END handle detached head
+		# END handle to_latest_revision option
+		
+		# update the working tree
+		if mrepo.head.commit.binsha != binsha:
+			if is_detached:
+				mrepo.git.checkout(hexsha)
+			else:
+				# TODO: allow to specify a rebase, merge, or reset
+				# TODO: Warn if the hexsha forces the tracking branch off the remote
+				# branch - this should be prevented when setting the branch option
+				mrepo.head.reset(hexsha, index=True, working_tree=True)
+			# END handle checkout
+		# END update to new commit only if needed
+		
+		# HANDLE RECURSION
+		##################
+		if recursive:
+			for submodule in self.iter_items(self.module()):
+				submodule.update(recursive, init, to_latest_revision)
+			# END handle recursive update
+		# END for each submodule
+			
+		return self
+		
+	@unbare_repo
+	def move(self, module_path, configuration=True, module=True):
+		"""Move the submodule to a another module path. This involves physically moving
+		the repository at our current path, changing the configuration, as well as
+		adjusting our index entry accordingly.
+		
+		:param module_path: the path to which to move our module, given as
+			repository-relative path. Intermediate directories will be created
+			accordingly. If the path already exists, it must be empty.
+			Trailling (back)slashes are removed automatically
+		:param configuration: if True, the configuration will be adjusted to let 
+			the submodule point to the given path.
+		:param module: if True, the repository managed by this submodule
+			will be moved, not the configuration. This will effectively 
+			leave your repository in an inconsistent state unless the configuration
+			and index already point to the target location.
+		:return: self
+		:raise ValueError: if the module path existed and was not empty, or was a file
+		:note: Currently the method is not atomic, and it could leave the repository
+			in an inconsistent state if a sub-step fails for some reason
+		"""
+		if module + configuration < 1:
+			raise ValueError("You must specify to move at least the module or the configuration of the submodule")
+		#END handle input
+		
+		module_path = to_native_path_linux(module_path)
+		if module_path.endswith('/'):
+			module_path = module_path[:-1]
+		# END handle trailing slash
+		
+		# VERIFY DESTINATION
+		if module_path == self.path:
+			return self
+		#END handle no change
+		
+		dest_path = join_path_native(self.repo.working_tree_dir, module_path)
+		if os.path.isfile(dest_path):
+			raise ValueError("Cannot move repository onto a file: %s" % dest_path)
+		# END handle target files
+		
+		index = self.repo.index
+		tekey = index.entry_key(module_path, 0)
+		# if the target item already exists, fail
+		if configuration and tekey in index.entries:
+			raise ValueError("Index entry for target path did alredy exist")
+		#END handle index key already there
+		
+		# remove existing destination
+		if module:
+			if os.path.exists(dest_path):
+				if len(os.listdir(dest_path)):
+					raise ValueError("Destination module directory was not empty")
+				#END handle non-emptyness
+				
+				if os.path.islink(dest_path):
+					os.remove(dest_path)
+				else:
+					os.rmdir(dest_path)
+				#END handle link
+			else:
+				# recreate parent directories
+				# NOTE: renames() does that now
+				pass
+			#END handle existance
+		# END handle module
+		
+		# move the module into place if possible
+		cur_path = self.abspath
+		renamed_module = False
+		if module and os.path.exists(cur_path):
+			os.renames(cur_path, dest_path)
+			renamed_module = True
+		#END move physical module
+		
+		
+		# rename the index entry - have to manipulate the index directly as 
+		# git-mv cannot be used on submodules ... yeah
+		try:
+			if configuration:
+				try:
+					ekey = index.entry_key(self.path, 0)
+					entry = index.entries[ekey]
+					del(index.entries[ekey])
+					nentry = git.IndexEntry(entry[:3]+(module_path,)+entry[4:])
+					index.entries[tekey] = nentry
+				except KeyError:
+					raise InvalidGitRepositoryError("Submodule's entry at %r did not exist" % (self.path))
+				#END handle submodule doesn't exist
+				
+				# update configuration
+				writer = self.config_writer(index=index)		# auto-write
+				writer.set_value('path', module_path)
+				self.path = module_path
+				del(writer)
+			# END handle configuration flag
+		except Exception:
+			if renamed_module:
+				os.renames(dest_path, cur_path)
+			# END undo module renaming
+			raise
+		#END handle undo rename
+		
+		return self
+		
+	@unbare_repo
+	def remove(self, module=True, force=False, configuration=True, dry_run=False):
+		"""Remove this submodule from the repository. This will remove our entry
+		from the .gitmodules file and the entry in the .git/config file.
+		
+		:param module: If True, the module we point to will be deleted 
+			as well. If the module is currently on a commit which is not part 
+			of any branch in the remote, if the currently checked out branch 
+			is ahead of its tracking branch,  if you have modifications in the
+			working tree, or untracked files,
+			In case the removal of the repository fails for these reasons, the 
+			submodule status will not have been altered.
+			If this submodule has child-modules on its own, these will be deleted
+			prior to touching the own module.
+		:param force: Enforces the deletion of the module even though it contains 
+			modifications. This basically enforces a brute-force file system based
+			deletion.
+		:param configuration: if True, the submodule is deleted from the configuration, 
+			otherwise it isn't. Although this should be enabled most of the times, 
+			this flag enables you to safely delete the repository of your submodule.
+		:param dry_run: if True, we will not actually do anything, but throw the errors
+			we would usually throw
+		:return: self
+		:note: doesn't work in bare repositories
+		:raise InvalidGitRepositoryError: thrown if the repository cannot be deleted
+		:raise OSError: if directories or files could not be removed"""
+		if not (module + configuration):
+			raise ValueError("Need to specify to delete at least the module, or the configuration")
+		# END handle params
+		
+		# DELETE MODULE REPOSITORY
+		##########################
+		if module and self.module_exists():
+			if force:
+				# take the fast lane and just delete everything in our module path
+				# TODO: If we run into permission problems, we have a highly inconsistent
+				# state. Delete the .git folders last, start with the submodules first
+				mp = self.abspath
+				method = None
+				if os.path.islink(mp):
+					method = os.remove
+				elif os.path.isdir(mp):
+					method = shutil.rmtree
+				elif os.path.exists(mp):
+					raise AssertionError("Cannot forcibly delete repository as it was neither a link, nor a directory")
+				#END handle brutal deletion
+				if not dry_run:
+					assert method
+					method(mp)
+				#END apply deletion method
+			else:
+				# verify we may delete our module
+				mod = self.module()
+				if mod.is_dirty(untracked_files=True):
+					raise InvalidGitRepositoryError("Cannot delete module at %s with any modifications, unless force is specified" % mod.working_tree_dir)
+				# END check for dirt
+				
+				# figure out whether we have new commits compared to the remotes
+				# NOTE: If the user pulled all the time, the remote heads might 
+				# not have been updated, so commits coming from the remote look
+				# as if they come from us. But we stay strictly read-only and
+				# don't fetch beforhand.
+				for remote in mod.remotes:
+					num_branches_with_new_commits = 0
+					rrefs = remote.refs
+					for rref in rrefs:
+						num_branches_with_new_commits = len(mod.git.cherry(rref)) != 0
+					# END for each remote ref
+					# not a single remote branch contained all our commits
+					if num_branches_with_new_commits == len(rrefs):
+						raise InvalidGitRepositoryError("Cannot delete module at %s as there are new commits" % mod.working_tree_dir)
+					# END handle new commits
+				# END for each remote
+				
+				# gently remove all submodule repositories
+				for sm in self.children():
+					sm.remove(module=True, force=False, configuration=False, dry_run=dry_run)
+				# END for each child-submodule
+				
+				# finally delete our own submodule
+				if not dry_run:
+					shutil.rmtree(mod.working_tree_dir)
+				# END delete tree if possible
+			# END handle force
+		# END handle module deletion
+			
+		# DELETE CONFIGURATION
+		######################
+		if configuration and not dry_run:
+			# first the index-entry
+			index = self.repo.index
+			try:
+				del(index.entries[index.entry_key(self.path, 0)])
+			except KeyError:
+				pass
+			#END delete entry
+			index.write()
+			
+			# now git config - need the config intact, otherwise we can't query 
+			# inforamtion anymore
+			self.repo.config_writer().remove_section(sm_section(self.name))
+			self.config_writer().remove_section()
+		# END delete configuration
+		
+		return self
+		
+	def set_parent_commit(self, commit, check=True):
+		"""Set this instance to use the given commit whose tree is supposed to 
+		contain the .gitmodules blob.
+		
+		:param commit: Commit'ish reference pointing at the root_tree
+		:param check: if True, relatively expensive checks will be performed to verify
+			validity of the submodule.
+		:raise ValueError: if the commit's tree didn't contain the .gitmodules blob.
+		:raise ValueError: if the parent commit didn't store this submodule under the
+			current path
+		:return: self"""
+		pcommit = self.repo.commit(commit)
+		pctree = pcommit.tree
+		if self.k_modules_file not in pctree:
+			raise ValueError("Tree of commit %s did not contain the %s file" % (commit, self.k_modules_file))
+		# END handle exceptions
+		
+		prev_pc = self._parent_commit
+		self._parent_commit = pcommit
+		
+		if check:
+			parser = self._config_parser(self.repo, self._parent_commit, read_only=True)
+			if not parser.has_section(sm_section(self.name)):
+				self._parent_commit = prev_pc
+				raise ValueError("Submodule at path %r did not exist in parent commit %s" % (self.path, commit)) 
+			# END handle submodule did not exist
+		# END handle checking mode
+		
+		# update our sha, it could have changed
+		self.binsha = pctree[self.path].binsha
+		
+		self._clear_cache()
+		
+		return self
+		
+	@unbare_repo
+	def config_writer(self, index=None, write=True):
+		""":return: a config writer instance allowing you to read and write the data
+		belonging to this submodule into the .gitmodules file.
+		
+		:param index: if not None, an IndexFile instance which should be written.
+			defaults to the index of the Submodule's parent repository.
+		:param write: if True, the index will be written each time a configuration
+			value changes.
+		:note: the parameters allow for a more efficient writing of the index, 
+			as you can pass in a modified index on your own, prevent automatic writing, 
+			and write yourself once the whole operation is complete
+		:raise ValueError: if trying to get a writer on a parent_commit which does not
+			match the current head commit
+		:raise IOError: If the .gitmodules file/blob could not be read"""
+		writer = self._config_parser_constrained(read_only=False)
+		if index is not None:
+			writer.config._index = index
+		writer.config._auto_write = write
+		return writer
+		
+	#} END edit interface
+	
+	#{ Query Interface
+	
+	@unbare_repo
+	def module(self):
+		""":return: Repo instance initialized from the repository at our submodule path
+		:raise InvalidGitRepositoryError: if a repository was not available. This could 
+			also mean that it was not yet initialized"""
+		# late import to workaround circular dependencies
+		module_path = self.abspath 
+		try:
+			repo = git.Repo(module_path)
+			if repo != self.repo:
+				return repo
+			# END handle repo uninitialized
+		except (InvalidGitRepositoryError, NoSuchPathError):
+			raise InvalidGitRepositoryError("No valid repository at %s" % self.path)
+		else:
+			raise InvalidGitRepositoryError("Repository at %r was not yet checked out" % module_path)
+		# END handle exceptions
+		
+	def module_exists(self):
+		""":return: True if our module exists and is a valid git repository. See module() method"""
+		try:
+			self.module()
+			return True
+		except Exception:
+			return False
+		# END handle exception
+	
+	def exists(self):
+		""":return: True if the submodule exists, False otherwise. Please note that
+		a submodule may exist (in the .gitmodules file) even though its module
+		doesn't exist"""
+		# keep attributes for later, and restore them if we have no valid data
+		# this way we do not actually alter the state of the object
+		loc = locals()
+		for attr in self._cache_attrs:
+			if hasattr(self, attr):
+				loc[attr] = getattr(self, attr)
+			# END if we have the attribute cache
+		#END for each attr
+		self._clear_cache()
+		
+		try:
+			try:
+				self.path
+				return True
+			except Exception:
+				return False
+			# END handle exceptions
+		finally:
+			for attr in self._cache_attrs:
+				if attr in loc:
+					setattr(self, attr, loc[attr])
+				# END if we have a cache
+			# END reapply each attribute
+		# END handle object state consistency
+	
+	@property
+	def branch(self):
+		""":return: The branch instance that we are to checkout"""
+		return self._branch
+	
+	@property
+	def url(self):
+		""":return: The url to the repository which our module-repository refers to"""
+		return self._url
+	
+	@property
+	def parent_commit(self):
+		""":return: Commit instance with the tree containing the .gitmodules file
+		:note: will always point to the current head's commit if it was not set explicitly"""
+		return self._parent_commit
+		
+	@property
+	def name(self):
+		""":return: The name of this submodule. It is used to identify it within the 
+			.gitmodules file.
+		:note: by default, the name is the path at which to find the submodule, but
+			in git-python it should be a unique identifier similar to the identifiers
+			used for remotes, which allows to change the path of the submodule
+			easily
+		"""
+		return self._name
+	
+	def config_reader(self):
+		""":return: ConfigReader instance which allows you to qurey the configuration values
+		of this submodule, as provided by the .gitmodules file
+		:note: The config reader will actually read the data directly from the repository
+			and thus does not need nor care about your working tree.
+		:note: Should be cached by the caller and only kept as long as needed
+		:raise IOError: If the .gitmodules file/blob could not be read"""
+		return self._config_parser_constrained(read_only=True)
+		
+	def children(self):
+		""":return: IterableList(Submodule, ...) an iterable list of submodules instances
+		which are children of this submodule
+		:raise InvalidGitRepositoryError: if the submodule is not checked-out"""
+		return self._get_intermediate_items(self)
+		
+	#} END query interface
+	
+	#{ Iterable Interface
+	
+	@classmethod
+	def iter_items(cls, repo, parent_commit='HEAD'):
+		""":return: iterator yielding Submodule instances available in the given repository"""
+		pc = repo.commit(parent_commit)			# parent commit instance
+		try:
+			parser = cls._config_parser(repo, pc, read_only=True)
+		except IOError:
+			raise StopIteration
+		# END handle empty iterator
+		
+		rt = pc.tree								# root tree
+		
+		for sms in parser.sections():
+			n = sm_name(sms)
+			p = parser.get_value(sms, 'path')
+			u = parser.get_value(sms, 'url')
+			b = cls.k_head_default
+			if parser.has_option(sms, cls.k_head_option):
+				b = parser.get_value(sms, cls.k_head_option)
+			# END handle optional information
+			
+			# get the binsha
+			index = repo.index
+			try:
+				sm = rt[p]
+			except KeyError:
+				# try the index, maybe it was just added
+				try:
+					entry = index.entries[index.entry_key(p, 0)]
+					sm = cls(repo, entry.binsha, entry.mode, entry.path)
+				except KeyError:
+					raise InvalidGitRepositoryError("Gitmodule path %r did not exist in revision of parent commit %s" % (p, parent_commit))
+				# END handle keyerror
+			# END handle critical error
+			
+			# fill in remaining info - saves time as it doesn't have to be parsed again
+			sm._name = n
+			sm._parent_commit = pc
+			sm._branch = mkhead(repo, b)
+			sm._url = u
+			
+			yield sm
+		# END for each section
+	
+	#} END iterable interface
+
diff --git a/lib/git/objects/submodule/root.py b/lib/git/objects/submodule/root.py
new file mode 100644
index 00000000..82b8b271
--- /dev/null
+++ b/lib/git/objects/submodule/root.py
@@ -0,0 +1,263 @@
+from base import Submodule
+from util import (
+					mkhead, 
+					find_first_remote_branch
+				)
+from git.exc import InvalidGitRepositoryError
+import git
+
+import sys
+
+__all__ = ["RootModule"]
+
+	
+class RootModule(Submodule):
+	"""A (virtual) Root of all submodules in the given repository. It can be used
+	to more easily traverse all submodules of the master repository"""
+	
+	__slots__ = tuple()
+	
+	k_root_name = '__ROOT__'
+	
+	def __init__(self, repo):
+		# repo, binsha, mode=None, path=None, name = None, parent_commit=None, url=None, ref=None)
+		super(RootModule, self).__init__(
+										repo, 
+										binsha = self.NULL_BIN_SHA, 
+										mode = self.k_default_mode, 
+										path = '', 
+										name = self.k_root_name, 
+										parent_commit = repo.head.commit,
+										url = '',
+										branch = mkhead(repo, self.k_head_default)
+										)
+		
+	
+	def _clear_cache(self):
+		"""May not do anything"""
+		pass
+	
+	#{ Interface 
+	
+	def update(self, previous_commit=None, recursive=True, force_remove=False, init=True, to_latest_revision=False):
+		"""Update the submodules of this repository to the current HEAD commit.
+		This method behaves smartly by determining changes of the path of a submodules
+		repository, next to changes to the to-be-checked-out commit or the branch to be 
+		checked out. This works if the submodules ID does not change.
+		Additionally it will detect addition and removal of submodules, which will be handled
+		gracefully.
+		
+		:param previous_commit: If set to a commit'ish, the commit we should use 
+			as the previous commit the HEAD pointed to before it was set to the commit it points to now. 
+			If None, it defaults to ORIG_HEAD otherwise, or the parent of the current
+			commit if it is not given
+		:param recursive: if True, the children of submodules will be updated as well
+			using the same technique
+		:param force_remove: If submodules have been deleted, they will be forcibly removed.
+			Otherwise the update may fail if a submodule's repository cannot be deleted as 
+			changes have been made to it (see Submodule.update() for more information)
+		:param init: If we encounter a new module which would need to be initialized, then do it.
+		:param to_latest_revision: If True, instead of checking out the revision pointed to 
+			by this submodule's sha, the checked out tracking branch will be merged with the 
+			newest remote branch fetched from the repository's origin"""
+		if self.repo.bare:
+			raise InvalidGitRepositoryError("Cannot update submodules in bare repositories")
+		# END handle bare
+		
+		repo = self.repo
+		
+		# HANDLE COMMITS
+		##################
+		cur_commit = repo.head.commit
+		if previous_commit is None:
+			symref = repo.head.orig_head()
+			try:
+				previous_commit = symref.commit
+			except Exception:
+				pcommits = cur_commit.parents
+				if pcommits:
+					previous_commit = pcommits[0]
+				else:
+					# in this special case, we just diff against ourselve, which
+					# means exactly no change
+					previous_commit = cur_commit
+				# END handle initial commit
+			# END no ORIG_HEAD
+		else:
+			previous_commit = repo.commit(previous_commit)	 # obtain commit object 
+		# END handle previous commit
+		
+		
+		psms = self.list_items(repo, parent_commit=previous_commit)
+		sms = self.list_items(self.module())
+		spsms = set(psms)
+		ssms = set(sms)
+		
+		# HANDLE REMOVALS
+		###################
+		for rsm in (spsms - ssms):
+			# fake it into thinking its at the current commit to allow deletion
+			# of previous module. Trigger the cache to be updated before that
+			#rsm.url
+			rsm._parent_commit = repo.head.commit
+			rsm.remove(configuration=False, module=True, force=force_remove)
+		# END for each removed submodule
+		
+		# HANDLE PATH RENAMES
+		#####################
+		# url changes + branch changes
+		for csm in (spsms & ssms):
+			psm = psms[csm.name]
+			sm = sms[csm.name]
+			
+			if sm.path != psm.path and psm.module_exists():
+				# move the module to the new path
+				psm.move(sm.path, module=True, configuration=False)
+			# END handle path changes
+			
+			if sm.module_exists():
+				# handle url change
+				if sm.url != psm.url:
+					# Add the new remote, remove the old one
+					# This way, if the url just changes, the commits will not 
+					# have to be re-retrieved
+					nn = '__new_origin__'
+					smm = sm.module()
+					rmts = smm.remotes
+					
+					# don't do anything if we already have the url we search in place
+					if len([r for r in rmts if r.url == sm.url]) == 0:
+						
+						
+						assert nn not in [r.name for r in rmts]
+						smr = smm.create_remote(nn, sm.url)
+						smr.fetch()
+						
+						# If we have a tracking branch, it should be available
+						# in the new remote as well.
+						if len([r for r in smr.refs if r.remote_head == sm.branch.name]) == 0:
+							raise ValueError("Submodule branch named %r was not available in new submodule remote at %r" % (sm.branch.name, sm.url))
+						# END head is not detached
+						
+						# now delete the changed one
+						rmt_for_deletion = None
+						for remote in rmts:
+							if remote.url == psm.url:
+								rmt_for_deletion = remote
+								break
+							# END if urls match
+						# END for each remote
+						
+						# if we didn't find a matching remote, but have exactly one, 
+						# we can safely use this one
+						if rmt_for_deletion is None:
+							if len(rmts) == 1:
+								rmt_for_deletion = rmts[0]
+							else:
+								# if we have not found any remote with the original url
+								# we may not have a name. This is a special case, 
+								# and its okay to fail here
+								# Alternatively we could just generate a unique name and leave all
+								# existing ones in place
+								raise InvalidGitRepositoryError("Couldn't find original remote-repo at url %r" % psm.url)
+							#END handle one single remote
+						# END handle check we found a remote
+						
+						orig_name = rmt_for_deletion.name
+						smm.delete_remote(rmt_for_deletion)
+						# NOTE: Currently we leave tags from the deleted remotes
+						# as well as separate tracking branches in the possibly totally 
+						# changed repository ( someone could have changed the url to 
+						# another project ). At some point, one might want to clean
+						# it up, but the danger is high to remove stuff the user
+						# has added explicitly
+						
+						# rename the new remote back to what it was
+						smr.rename(orig_name)
+						
+						# early on, we verified that the our current tracking branch
+						# exists in the remote. Now we have to assure that the 
+						# sha we point to is still contained in the new remote
+						# tracking branch.
+						smsha = sm.binsha
+						found = False
+						rref = smr.refs[self.branch.name]
+						for c in rref.commit.traverse():
+							if c.binsha == smsha:
+								found = True
+								break
+							# END traverse all commits in search for sha
+						# END for each commit
+						
+						if not found:
+							# adjust our internal binsha to use the one of the remote
+							# this way, it will be checked out in the next step
+							# This will change the submodule relative to us, so 
+							# the user will be able to commit the change easily
+							print >> sys.stderr, "WARNING: Current sha %s was not contained in the tracking branch at the new remote, setting it the the remote's tracking branch" % sm.hexsha
+							sm.binsha = rref.commit.binsha
+						#END reset binsha
+						
+						#NOTE: All checkout is performed by the base implementation of update
+						
+					# END skip remote handling if new url already exists in module
+				# END handle url
+				
+				if sm.branch != psm.branch:
+					# finally, create a new tracking branch which tracks the 
+					# new remote branch
+					smm = sm.module()
+					smmr = smm.remotes
+					try:
+						tbr = git.Head.create(smm, sm.branch.name)
+					except git.GitCommandError, e:
+						if e.status != 128:
+							raise
+						#END handle something unexpected
+						
+						# ... or reuse the existing one
+						tbr = git.Head(smm, git.Head.to_full_path(sm.branch.name))
+					#END assure tracking branch exists
+					
+					tbr.set_tracking_branch(find_first_remote_branch(smmr, sm.branch))
+					# figure out whether the previous tracking branch contains
+					# new commits compared to the other one, if not we can 
+					# delete it.
+					try:
+						tbr = find_first_remote_branch(smmr, psm.branch)
+						if len(smm.git.cherry(tbr, psm.branch)) == 0:
+							psm.branch.delete(smm, psm.branch)
+						#END delete original tracking branch if there are no changes
+					except InvalidGitRepositoryError:
+						# ignore it if the previous branch couldn't be found in the
+						# current remotes, this just means we can't handle it
+						pass
+					# END exception handling
+					
+					#NOTE: All checkout is done in the base implementation of update
+					
+				#END handle branch
+			#END handle 
+		# END for each common submodule 
+		
+		# FINALLY UPDATE ALL ACTUAL SUBMODULES
+		######################################
+		for sm in sms:
+			# update the submodule using the default method
+			sm.update(recursive=True, init=init, to_latest_revision=to_latest_revision)
+			
+			# update recursively depth first - question is which inconsitent 
+			# state will be better in case it fails somewhere. Defective branch
+			# or defective depth. The RootSubmodule type will never process itself, 
+			# which was done in the previous expression
+			if recursive:
+				type(self)(sm.module()).update(recursive=True, force_remove=force_remove, 
+											init=init, to_latest_revision=to_latest_revision)
+			#END handle recursive
+		# END for each submodule to update
+
+	def module(self):
+		""":return: the actual repository containing the submodules"""
+		return self.repo
+	#} END interface
+#} END classes
diff --git a/lib/git/objects/submodule/util.py b/lib/git/objects/submodule/util.py
new file mode 100644
index 00000000..ab5e345a
--- /dev/null
+++ b/lib/git/objects/submodule/util.py
@@ -0,0 +1,101 @@
+import git
+from git.exc import InvalidGitRepositoryError
+from git.config import GitConfigParser
+from StringIO import StringIO
+import weakref
+
+__all__ = (	'sm_section', 'sm_name', 'mkhead', 'unbare_repo', 'find_first_remote_branch', 
+			'SubmoduleConfigParser')
+
+#{ Utilities
+
+def sm_section(name):
+	""":return: section title used in .gitmodules configuration file"""
+	return 'submodule "%s"' % name
+
+def sm_name(section):
+	""":return: name of the submodule as parsed from the section name"""
+	section = section.strip()
+	return section[11:-1]
+	
+def mkhead(repo, path):
+	""":return: New branch/head instance"""
+	return git.Head(repo, git.Head.to_full_path(path))
+	
+def unbare_repo(func):
+	"""Methods with this decorator raise InvalidGitRepositoryError if they 
+	encounter a bare repository"""
+	def wrapper(self, *args, **kwargs):
+		if self.repo.bare:
+			raise InvalidGitRepositoryError("Method '%s' cannot operate on bare repositories" % func.__name__)
+		#END bare method
+		return func(self, *args, **kwargs)
+	# END wrapper
+	wrapper.__name__ = func.__name__
+	return wrapper
+	
+def find_first_remote_branch(remotes, branch):
+	"""Find the remote branch matching the name of the given branch or raise InvalidGitRepositoryError"""
+	for remote in remotes:
+		try:
+			return remote.refs[branch.name]
+		except IndexError:
+			continue
+		# END exception handling
+	#END for remote
+	raise InvalidGitRepositoryError("Didn't find remote branch %r in any of the given remotes", branch)
+	
+#} END utilities
+
+
+#{ Classes
+
+class SubmoduleConfigParser(GitConfigParser):
+	"""
+	Catches calls to _write, and updates the .gitmodules blob in the index
+	with the new data, if we have written into a stream. Otherwise it will 
+	add the local file to the index to make it correspond with the working tree.
+	Additionally, the cache must be cleared
+	
+	Please note that no mutating method will work in bare mode
+	"""
+	
+	def __init__(self, *args, **kwargs):
+		self._smref = None
+		self._index = None
+		self._auto_write = True
+		super(SubmoduleConfigParser, self).__init__(*args, **kwargs)
+	
+	#{ Interface
+	def set_submodule(self, submodule):
+		"""Set this instance's submodule. It must be called before 
+		the first write operation begins"""
+		self._smref = weakref.ref(submodule)
+
+	def flush_to_index(self):
+		"""Flush changes in our configuration file to the index"""
+		assert self._smref is not None
+		# should always have a file here
+		assert not isinstance(self._file_or_files, StringIO)
+		
+		sm = self._smref()
+		if sm is not None:
+			index = self._index
+			if index is None:
+				index = sm.repo.index
+			# END handle index
+			index.add([sm.k_modules_file], write=self._auto_write)
+			sm._clear_cache()
+		# END handle weakref
+
+	#} END interface
+	
+	#{ Overridden Methods
+	def write(self):
+		rval = super(SubmoduleConfigParser, self).write()
+		self.flush_to_index()
+		return rval
+	# END overridden methods
+
+
+#} END classes
diff --git a/lib/git/objects/tag.py b/lib/git/objects/tag.py
index ea480fc2..c7d02abe 100644
--- a/lib/git/objects/tag.py
+++ b/lib/git/objects/tag.py
@@ -33,7 +33,18 @@ class TagObject(base.Object):
 		:param tagged_tz_offset: int_seconds_west_of_utc is the timezone that the 
 			authored_date is in, in a format similar to time.altzone"""
 		super(TagObject, self).__init__(repo, binsha )
-		self._set_self_from_args_(locals())
+		if object is not None:
+			self.object = object
+		if tag is not None:
+			self.tag = tag
+		if tagger is not None:
+			self.tagger = tagger
+		if tagged_date is not None:
+			self.tagged_date = tagged_date
+		if tagger_tz_offset is not None:
+			self.tagger_tz_offset = tagger_tz_offset
+		if message is not None:
+			self.message = message
 		
 	def _set_cache_(self, attr):
 		"""Cache all our attributes at once"""
diff --git a/lib/git/objects/tree.py b/lib/git/objects/tree.py
index 68c1ef2d..67431686 100644
--- a/lib/git/objects/tree.py
+++ b/lib/git/objects/tree.py
@@ -7,7 +7,7 @@ import util
 from base import IndexObject
 from git.util import join_path
 from blob import Blob
-from submodule import Submodule
+from submodule.base import Submodule
 import git.diff as diff
 
 from fun import (
diff --git a/lib/git/objects/util.py b/lib/git/objects/util.py
index 21833080..81544e26 100644
--- a/lib/git/objects/util.py
+++ b/lib/git/objects/util.py
@@ -4,6 +4,8 @@
 # This module is part of GitPython and is released under
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
 """Module for general utility functions"""
+from git.util import IterableList
+
 import re
 from collections import deque as Deque
 import platform
@@ -273,6 +275,12 @@ class Traversable(object):
 		"""
 		raise NotImplementedError("To be implemented in subclass")
 			
+	def list_traverse(self, *args, **kwargs):
+		""":return: IterableList with the results of the traversal as produced by
+			traverse()"""
+		out = IterableList(self._id_attribute_)
+		out.extend(self.traverse(*args, **kwargs))
+		return out
 	
 	def traverse( self, predicate = lambda i,d: True,
 						   prune = lambda i,d: False, depth = -1, branch_first=True,
@@ -335,7 +343,7 @@ class Traversable(object):
 			if prune( rval, d ):
 				continue
 	
-			skipStartItem = ignore_self and ( item == self )
+			skipStartItem = ignore_self and ( item is self )
 			if not skipStartItem and predicate( rval, d ):
 				yield rval