git_drover: Replace with instructions on how to cherry-pick.
Change-Id: I4cf7591df2b89bceb5618abb8fad92fd29e066bf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2653952
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Andy Perelson <ajp@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
diff --git a/git_drover.py b/git_drover.py
index 52bff63..4991219 100755
--- a/git_drover.py
+++ b/git_drover.py
@@ -2,468 +2,47 @@
# Copyright 2015 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
-"""git drover: A tool for merging changes to release branches."""
from __future__ import print_function
import argparse
-import functools
-import logging
-import os
-import re
-import shutil
-import subprocess
-import sys
-import tempfile
-
-import git_common
-import gclient_utils
-
-if sys.version_info.major == 2:
- import cPickle
-else:
- import pickle as cPickle
-
-class Error(Exception):
- pass
-_PATCH_ERROR_MESSAGE = """Patch failed to apply.
+_HELP_MESSAGE = """\
+git drover has been deprecated in favor of cherry-picking using Gerrit.
+Try it, it's faster!
-A workdir for this cherry-pick has been created in
- {0}
+See https://www.chromium.org/developers/how-tos/drover for instructions.
-To continue, resolve the conflicts there and run
- git drover --continue {0}
+If the Gerrit UI is not sufficient, and you know what you're doing:
+ git checkout -b branch-name refs/remotes/branch-heads/{branch}
+ git cherry-pick -x {cherry_pick}
-To abort this cherry-pick run
- git drover --abort {0}
+If you have to do a lot of merges, consider using multiple working directories
+in your checkout:
+https://www.chromium.org/developers/how-tos/get-the-code/multiple-working-directories
"""
-class PatchError(Error):
- """An error indicating that the patch failed to apply."""
-
- def __init__(self, workdir):
- super(PatchError, self).__init__(_PATCH_ERROR_MESSAGE.format(workdir))
-
-
-_DEV_NULL_FILE = open(os.devnull, 'w')
-
-if os.name == 'nt':
- # This is a just-good-enough emulation of os.symlink for drover to work on
- # Windows. It uses junctioning of directories (most of the contents of
- # the .git directory), but copies files. Note that we can't use
- # CreateSymbolicLink or CreateHardLink here, as they both require elevation.
- # Creating reparse points is what we want for the directories, but doing so
- # is a relatively messy set of DeviceIoControl work at the API level, so we
- # simply shell to `mklink /j` instead.
- def emulate_symlink_windows(source, link_name):
- if os.path.isdir(source):
- subprocess.check_call(['mklink', '/j',
- link_name.replace('/', '\\'),
- source.replace('/', '\\')],
- shell=True)
- else:
- shutil.copy(source, link_name)
- mk_symlink = emulate_symlink_windows
-else:
- mk_symlink = os.symlink
-
-
-class _Drover(object):
-
- def __init__(self, branch, revision, parent_repo, dry_run, verbose):
- self._branch = branch
- self._branch_ref = 'refs/remotes/branch-heads/%s' % branch
- self._revision = revision
- self._parent_repo = os.path.abspath(parent_repo)
- self._dry_run = dry_run
- self._workdir = None
- self._branch_name = None
- self._needs_cleanup = True
- self._verbose = verbose
- self._process_options()
-
- def _process_options(self):
- if self._verbose:
- logging.getLogger().setLevel(logging.DEBUG)
-
-
- @classmethod
- def resume(cls, workdir):
- """Continues a cherry-pick that required manual resolution.
-
- Args:
- workdir: A string containing the path to the workdir used by drover.
- """
- drover = cls._restore_drover(workdir)
- drover._continue()
-
- @classmethod
- def abort(cls, workdir):
- """Aborts a cherry-pick that required manual resolution.
-
- Args:
- workdir: A string containing the path to the workdir used by drover.
- """
- drover = cls._restore_drover(workdir)
- drover._cleanup()
-
- @staticmethod
- def _restore_drover(workdir):
- """Restores a saved drover state contained within a workdir.
-
- Args:
- workdir: A string containing the path to the workdir used by drover.
- """
- try:
- with open(os.path.join(workdir, '.git', 'drover'), 'rb') as f:
- drover = cPickle.load(f)
- drover._process_options()
- return drover
- except (IOError, cPickle.UnpicklingError):
- raise Error('%r is not git drover workdir' % workdir)
-
- def _continue(self):
- if os.path.exists(os.path.join(self._workdir, '.git', 'CHERRY_PICK_HEAD')):
- self._run_git_command(
- ['commit', '--no-edit'],
- error_message='All conflicts must be resolved before continuing')
-
- if self._upload_and_land():
- # Only clean up the workdir on success. The manually resolved cherry-pick
- # can be reused if the user cancels before landing.
- self._cleanup()
-
- def run(self):
- """Runs this Drover instance.
-
- Raises:
- Error: An error occurred while attempting to cherry-pick this change.
- """
- try:
- self._run_internal()
- finally:
- self._cleanup()
-
- def _run_internal(self):
- self._check_inputs()
- if not self._confirm('Going to cherry-pick\n"""\n%s"""\nto %s.' % (
- self._run_git_command(['show', '-s', self._revision]), self._branch)):
- return
- self._create_checkout()
- self._perform_cherry_pick()
- self._upload_and_land()
-
- def _cleanup(self):
- if not self._needs_cleanup:
- return
-
- if self._workdir:
- logging.debug('Deleting %s', self._workdir)
- if os.name == 'nt':
- try:
- # Use rmdir to properly handle the junctions we created.
- subprocess.check_call(
- ['rmdir', '/s', '/q', self._workdir], shell=True)
- except subprocess.CalledProcessError:
- logging.error(
- 'Failed to delete workdir %r. Please remove it manually.',
- self._workdir)
- else:
- shutil.rmtree(self._workdir)
- self._workdir = None
- if self._branch_name:
- self._run_git_command(['branch', '-D', self._branch_name])
-
- @staticmethod
- def _confirm(message):
- """Show a confirmation prompt with the given message.
-
- Returns:
- A bool representing whether the user wishes to continue.
- """
- result = ''
- while result not in ('y', 'n'):
- try:
- result = gclient_utils.AskForData('%s Continue (y/n)? ' % message)
- except EOFError:
- result = 'n'
- return result == 'y'
-
- def _check_inputs(self):
- """Check the input arguments and ensure the parent repo is up to date."""
-
- if not os.path.isdir(self._parent_repo):
- raise Error('Invalid parent repo path %r' % self._parent_repo)
-
- self._run_git_command(['--help'], error_message='Unable to run git')
- self._run_git_command(['status'],
- error_message='%r is not a valid git repo' %
- os.path.abspath(self._parent_repo))
- self._run_git_command(['fetch', 'origin'],
- error_message='Failed to fetch origin')
- self._run_git_command(
- ['rev-parse', '%s^{commit}' % self._branch_ref],
- error_message='Branch %s not found' % self._branch_ref)
- self._run_git_command(
- ['rev-parse', '%s^{commit}' % self._revision],
- error_message='Revision "%s" not found' % self._revision)
-
- FILES_TO_LINK = [
- 'refs',
- 'logs/refs',
- 'info/refs',
- 'info/exclude',
- 'objects',
- 'hooks',
- 'packed-refs',
- 'remotes',
- 'rr-cache',
- ]
- FILES_TO_COPY = ['config', 'HEAD']
-
- def _create_checkout(self):
- """Creates a checkout to use for cherry-picking.
-
- This creates a checkout similarly to git-new-workdir. Most of the .git
- directory is shared with the |self._parent_repo| using symlinks. This
- differs from git-new-workdir in that the config is forked instead of shared.
- This is so the new workdir can be a sparse checkout without affecting
- |self._parent_repo|.
- """
- parent_git_dir = os.path.join(self._parent_repo, self._run_git_command(
- ['rev-parse', '--git-dir']).strip())
- self._workdir = tempfile.mkdtemp(prefix='drover_%s_' % self._branch)
- logging.debug('Creating checkout in %s', self._workdir)
- git_dir = os.path.join(self._workdir, '.git')
- git_common.make_workdir_common(parent_git_dir, git_dir, self.FILES_TO_LINK,
- self.FILES_TO_COPY, mk_symlink)
- self._run_git_command(['config', 'core.sparsecheckout', 'true'])
- with open(os.path.join(git_dir, 'info', 'sparse-checkout'), 'w') as f:
- f.write('/codereview.settings')
-
- branch_name = os.path.split(self._workdir)[-1]
- self._run_git_command(['checkout', '-b', branch_name, self._branch_ref])
- self._branch_name = branch_name
-
- def _perform_cherry_pick(self):
- try:
- self._run_git_command(['cherry-pick', '-x', self._revision],
- error_message='Patch failed to apply')
- except Error:
- self._prepare_manual_resolve()
- self._save_state()
- self._needs_cleanup = False
- raise PatchError(self._workdir)
-
- def _save_state(self):
- """Saves the state of this Drover instances to the workdir."""
- with open(os.path.join(self._workdir, '.git', 'drover'), 'wb') as f:
- cPickle.dump(self, f)
-
- def _prepare_manual_resolve(self):
- """Prepare the workdir for the user to manually resolve the cherry-pick."""
- # Files that have been deleted between branch and cherry-pick will not have
- # their skip-worktree bit set so set it manually for those files to avoid
- # git status incorrectly listing them as unstaged deletes.
- repo_status = self._run_git_command(
- ['-c', 'core.quotePath=false', 'status', '--porcelain']).splitlines()
- extra_files = [f[3:] for f in repo_status if f[:2] == ' D']
- if extra_files:
- stdin = '\n'.join(extra_files) + '\n'
- self._run_git_command_with_stdin(
- ['update-index', '--skip-worktree', '--stdin'], stdin=stdin.encode())
-
- def _upload_and_land(self):
- if self._dry_run:
- logging.info('--dry_run enabled; not landing.')
- return True
-
- self._run_git_command(['reset', '--hard'])
-
- author = self._run_git_command(['log', '-1', '--format=%ae']).strip()
- self._run_git_command(['cl', 'upload', '--send-mail', '--tbrs', author],
- error_message='Upload failed',
- interactive=True)
-
- if not self._confirm('About to start CQ on %s.' % self._branch):
- return False
- self._run_git_command(['cl', 'set-commit'], interactive=True)
- return True
-
- def _run_git_command(self, args, error_message=None, interactive=False):
- """Runs a git command.
-
- Args:
- args: A list of strings containing the args to pass to git.
- error_message: A string containing the error message to report if the
- command fails.
- interactive: A bool containing whether the command requires user
- interaction. If false, the command will be provided with no input and
- the output is captured.
-
- Returns:
- stdout as a string, or stdout interleaved with stderr if self._verbose
-
- Raises:
- Error: The command failed to complete successfully.
- """
- cwd = self._workdir if self._workdir else self._parent_repo
- logging.debug('Running git %s (cwd %r)', ' '.join('%s' % arg
- for arg in args), cwd)
-
- run = subprocess.check_call if interactive else subprocess.check_output
-
- # Discard stderr unless verbose is enabled.
- stderr = None if self._verbose else _DEV_NULL_FILE
-
- try:
- rv = run(['git'] + args, shell=False, cwd=cwd, stderr=stderr)
- if not interactive and sys.version_info.major == 3:
- return rv.decode('utf-8', 'ignore')
- return rv
- except (OSError, subprocess.CalledProcessError) as e:
- if error_message:
- raise Error(error_message)
- else:
- raise Error('Command %r failed: %s' % (' '.join(args), e))
-
- def _run_git_command_with_stdin(self, args, stdin):
- """Runs a git command with a provided stdin.
-
- Args:
- args: A list of strings containing the args to pass to git.
- stdin: A string to provide on stdin.
-
- Returns:
- stdout as a string, or stdout interleaved with stderr if self._verbose
-
- Raises:
- Error: The command failed to complete successfully.
- """
- cwd = self._workdir if self._workdir else self._parent_repo
- logging.debug('Running git %s (cwd %r)', ' '.join('%s' % arg
- for arg in args), cwd)
-
- # Discard stderr unless verbose is enabled.
- stderr = None if self._verbose else _DEV_NULL_FILE
-
- try:
- popen = subprocess.Popen(['git'] + args, shell=False, cwd=cwd,
- stderr=stderr, stdin=subprocess.PIPE)
- popen.communicate(stdin)
- if popen.returncode != 0:
- raise Error('Command %r failed' % ' '.join(args))
- except OSError as e:
- raise Error('Command %r failed: %s' % (' '.join(args), e))
-
-
-def cherry_pick_change(branch, revision, parent_repo, dry_run, verbose=False):
- """Cherry-picks a change into a branch.
-
- Args:
- branch: A string containing the release branch number to which to
- cherry-pick.
- revision: A string containing the revision to cherry-pick. It can be any
- string that git-rev-parse can identify as referring to a single
- revision.
- parent_repo: A string containing the path to the parent repo to use for this
- cherry-pick.
- dry_run: A bool containing whether to stop before uploading the
- cherry-pick cl.
- verbose: A bool containing whether to print verbose logging.
-
- Raises:
- Error: An error occurred while attempting to cherry-pick |cl| to |branch|.
- """
- drover = _Drover(branch, revision, parent_repo, dry_run, verbose)
- drover.run()
-
-
-def continue_cherry_pick(workdir):
- """Continues a cherry-pick that required manual resolution.
-
- Args:
- workdir: A string containing the path to the workdir used by drover.
- """
- _Drover.resume(workdir)
-
-
-def abort_cherry_pick(workdir):
- """Aborts a cherry-pick that required manual resolution.
-
- Args:
- workdir: A string containing the path to the workdir used by drover.
- """
- _Drover.abort(workdir)
-
-
def main():
- parser = argparse.ArgumentParser(
- description='Cherry-pick a change into a release branch.')
- group = parser.add_mutually_exclusive_group(required=True)
+ parser = argparse.ArgumentParser(description=_HELP_MESSAGE)
parser.add_argument(
'--branch',
+ default='BRANCH',
+ metavar='BRANCH',
type=str,
- metavar='<branch>',
help='the name of the branch to which to cherry-pick; e.g. 1234')
- group.add_argument(
+ parser.add_argument(
'--cherry-pick',
+ default='HASH_OF_THE_COMMIT_TO_CHERRY_PICK',
+ metavar='HASH_OF_THE_COMMIT_TO_CHERRY_PICK',
type=str,
- metavar='<change>',
help=('the change to cherry-pick; this can be any string '
- 'that unambiguously refers to a revision not involving HEAD'))
- group.add_argument(
- '--continue',
- type=str,
- nargs='?',
- dest='resume',
- const=os.path.abspath('.'),
- metavar='path_to_workdir',
- help='Continue a drover cherry-pick after resolving conflicts')
- group.add_argument('--abort',
- type=str,
- nargs='?',
- const=os.path.abspath('.'),
- metavar='path_to_workdir',
- help='Abort a drover cherry-pick')
- parser.add_argument(
- '--parent_checkout',
- type=str,
- default=os.path.abspath('.'),
- metavar='<path_to_parent_checkout>',
- help=('the path to the chromium checkout to use as the source for a '
- 'creating git-new-workdir workdir to use for cherry-picking; '
- 'if unspecified, the current directory is used'))
- parser.add_argument(
- '--dry-run',
- action='store_true',
- default=False,
- help=("don't actually upload and land; "
- "just check that cherry-picking would succeed"))
- parser.add_argument('-v',
- '--verbose',
- action='store_true',
- default=False,
- help='show verbose logging')
- options = parser.parse_args()
- try:
- if options.resume:
- _Drover.resume(options.resume)
- elif options.abort:
- _Drover.abort(options.abort)
- else:
- if not options.branch:
- parser.error('argument --branch is required for --cherry-pick')
- cherry_pick_change(options.branch, options.cherry_pick,
- options.parent_checkout, options.dry_run,
- options.verbose)
- except Error as e:
- print('Error:', e)
- sys.exit(128)
+ 'that unambiguosly refers to a revision not involving HEAD'))
+ options, _ = parser.parse_known_args()
+ print(_HELP_MESSAGE.format(
+ branch=options.branch, cherry_pick=options.cherry_pick))
if __name__ == '__main__':
main()