Implemented dry_run mode including tests for RootModule.update and Submodule

Author: Byron

objects/submodule/base.py

@@ -329,6 +329,15 @@ def update(self, recursive=False, init=True, to_latest_revision=False, progress=
 		if progress is None:
 			progress = UpdateProgress()
 		#END handle progress
+		prefix = ''
+		if dry_run:
+			prefix = "DRY-RUN: "
+		#END handle prefix
+		
+		# to keep things plausible in dry-run mode
+		if dry_run:
+			mrepo = None
+		#END init mrepo
 
 		# ASSURE REPO IS PRESENT AND UPTODATE
 		#####################################
@@ -342,14 +351,16 @@ def update(self, recursive=False, init=True, to_latest_revision=False, progress=
 					op |= BEGIN
 				#END handle start
 
-				progress.update(op, i, len_rmts, "Fetching remote %s" % remote)
+				progress.update(op, i, len_rmts, prefix+"Fetching remote %s of submodule %r" % (remote, self.name))
 				#===============================
-				remote.fetch(progress=progress)
+				if not dry_run:
+					remote.fetch(progress=progress)
+				#END handle dry-run
 				#===============================
 				if i == len_rmts-1:
 					op |= END
 				#END handle end
-				progress.update(op, i, len_rmts, "Done fetching remote %s" % remote)
+				progress.update(op, i, len_rmts, prefix+"Done fetching remote of submodule %r" % self.name)
 			#END fetch new data
 		except InvalidGitRepositoryError:
 			if not init:
@@ -359,7 +370,7 @@ def update(self, recursive=False, init=True, to_latest_revision=False, progress=
 
 			# 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):
+			if not dry_run and os.path.isdir(module_path):
 				try:
 					os.rmdir(module_path)
 				except OSError:
@@ -369,42 +380,51 @@ def update(self, recursive=False, init=True, to_latest_revision=False, progress=
 
 			# don't check it out at first - nonetheless it will create a local
 			# branch according to the remote-HEAD if possible
-			progress.update(BEGIN|CLONE, 0, 1, "Cloning %s to %s" % (self.url, module_path))
-			mrepo = git.Repo.clone_from(self.url, module_path, n=True)
-			progress.update(END|CLONE, 0, 1, "Done cloning to %s" % module_path)
+			progress.update(BEGIN|CLONE, 0, 1, prefix+"Cloning %s to %s in submodule %r" % (self.url, module_path, self.name))
+			if not dry_run:
+				mrepo = git.Repo.clone_from(self.url, module_path, n=True)
+			#END handle dry-run
+			progress.update(END|CLONE, 0, 1, prefix+"Done cloning to %s" % module_path)
 
-			# 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_name)
-				local_branch = mkhead(mrepo, self.branch_path)
-				
-				# have a valid branch, but no checkout - make sure we can figure
-				# that out by marking the commit with a null_sha
-				local_branch.set_object(util.Object(mrepo, self.NULL_BIN_SHA))
-				# END initial checkout + branch creation
-				
-				# make sure HEAD is not detached
-				mrepo.head.set_reference(local_branch, logmsg="submodule: attaching head to %s" % local_branch)
-				mrepo.head.ref.set_tracking_branch(remote_branch)
-			except IndexError:
-				print >> sys.stderr, "Warning: Failed to checkout tracking branch %s" % self.branch_path 
-			#END handle tracking branch
 
-			# 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 !
-			self.repo.config_writer().set_value(sm_section(self.name), 'url', self.url)
+			if not dry_run:
+				# 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_name)
+					local_branch = mkhead(mrepo, self.branch_path)
+					
+					# have a valid branch, but no checkout - make sure we can figure
+					# that out by marking the commit with a null_sha
+					local_branch.set_object(util.Object(mrepo, self.NULL_BIN_SHA))
+					# END initial checkout + branch creation
+					
+					# make sure HEAD is not detached
+					mrepo.head.set_reference(local_branch, logmsg="submodule: attaching head to %s" % local_branch)
+					mrepo.head.ref.set_tracking_branch(remote_branch)
+				except IndexError:
+					print >> sys.stderr, "Warning: Failed to checkout tracking branch %s" % self.branch_path 
+				#END handle tracking branch
+				
+				# 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 !
+				self.repo.config_writer().set_value(sm_section(self.name), 'url', self.url)
+			#END handle dry_run
 		#END handle initalization
 
 
 		# DETERMINE SHAS TO CHECKOUT
 		############################
 		binsha = self.binsha
 		hexsha = self.hexsha
-		is_detached = mrepo.head.is_detached
-		if to_latest_revision:
+		if mrepo is not None:
+			# mrepo is only set if we are not in dry-run mode or if the module existed
+			is_detached = mrepo.head.is_detached
+		#END handle dry_run
+		
+		if not dry_run and 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()
@@ -421,29 +441,35 @@ def update(self, recursive=False, init=True, to_latest_revision=False, progress=
 		# END handle to_latest_revision option
 
 		# update the working tree
-		if mrepo.head.commit.binsha != binsha:
-			progress.update(BEGIN|UPDWKTREE, 0, 1, "Updating working tree at %s" % self.path)
-			if is_detached:
-				# NOTE: for now we force, the user is no supposed to change detached
-				# submodules anyway. Maybe at some point this becomes an option, to 
-				# properly handle user modifications - see below for future options
-				# regarding rebase and merge.
-				mrepo.git.checkout(hexsha, force=True)
-			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
-			progress.update(END|UPDWKTREE, 0, 1, "Done updating working tree at %s" % self.path)
+		# handles dry_run
+		if mrepo is not None and mrepo.head.commit.binsha != binsha:
+			progress.update(BEGIN|UPDWKTREE, 0, 1, prefix+"Updating working tree at %s for submodule %r" % (self.path, self.name))
+			if not dry_run:
+				if is_detached:
+					# NOTE: for now we force, the user is no supposed to change detached
+					# submodules anyway. Maybe at some point this becomes an option, to 
+					# properly handle user modifications - see below for future options
+					# regarding rebase and merge.
+					mrepo.git.checkout(hexsha, force=True)
+				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 handle dry_run
+			progress.update(END|UPDWKTREE, 0, 1, prefix+"Done updating working tree for submodule %r" % self.name)
 		# 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, progress=progress)
-			# END handle recursive update
+			# in dry_run mode, the module might not exist
+			if mrepo is not None:
+				for submodule in self.iter_items(self.module()):
+					submodule.update(recursive, init, to_latest_revision, progress=progress, dry_run=dry_run)
+				# END handle recursive update
+			#END handle dry run
 		# END for each submodule
 
 		return self
@@ -843,8 +869,7 @@ def config_reader(self):
 	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"""
+			which are children of this submodule or 0 if the submodule is not checked out"""
 		return self._get_intermediate_items(self)
 
 	#} END query interface