[gentoo-portage-dev] [PATCH] GitSync.update: respect sync-depth (bug 552814)

[Zac Medico <zmedico@gentoo.org>]

Fix updates to respect sync-depth (previously it was only respected
for clone operations). Since the default merge strategy typically
fails when the the depth is not unlimited, use `git fetch` followed
by `git reset --hard`.

X-Gentoo-Bug: 552814
X-Gentoo-Bug-url: https://bugs.gentoo.org/show_bug.cgi?id=552814
---
 pym/portage/sync/modules/git/git.py | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/pym/portage/sync/modules/git/git.py b/pym/portage/sync/modules/git/git.py
index 02eeb16..62c24f6 100644
--- a/pym/portage/sync/modules/git/git.py
+++ b/pym/portage/sync/modules/git/git.py
@@ -83,7 +83,21 @@ class GitSync(NewBase):
 			git_cmd_opts += " --quiet"
 		if self.repo.module_specific_options.get('sync-git-pull-extra-opts'):
 			git_cmd_opts += " %s" % self.repo.module_specific_options['sync-git-pull-extra-opts']
-		git_cmd = "%s pull%s" % (self.bin_command, git_cmd_opts)
+		if self.repo.sync_depth is None:
+			git_cmd = "%s pull%s" % (self.bin_command, git_cmd_opts)
+		else:
+			# Since the default merge strategy typically fails when
+			# the depth is not unlimited, use `git fetch` followed by
+			# `git reset --hard`.
+			remote_branch = portage._unicode_decode(
+				subprocess.check_output([self.bin_command, 'rev-parse',
+				'--abbrev-ref', '--symbolic-full-name', '@{upstream}'],
+				cwd=portage._unicode_encode(self.repo.location))).rstrip('\n')
+
+			git_cmd_opts += " --depth %d" % self.repo.sync_depth
+			git_cmd = "%s fetch %s%s" % (self.bin_command,
+				remote_branch.partition('/')[0], git_cmd_opts)
+
 		writemsg_level(git_cmd + "\n")
 
 		rev_cmd = [self.bin_command, "rev-list", "--max-count=1", "HEAD"]
@@ -93,6 +107,12 @@ class GitSync(NewBase):
 		exitcode = portage.process.spawn_bash("cd %s ; exec %s" % (
 				portage._shell_quote(self.repo.location), git_cmd),
 			**self.spawn_kwargs)
+
+		if exitcode == os.EX_OK and self.repo.sync_depth is not None:
+			exitcode = subprocess.call(
+				[self.bin_command, 'reset', '--hard', remote_branch],
+				cwd=portage._unicode_encode(self.repo.location))
+
 		if exitcode != os.EX_OK:
 			msg = "!!! git pull error in %s" % self.repo.location
 			self.logger(self.xterm_titles, msg)
-- 
2.7.4