git-repo/subcmds/cherry_pick.py
Than McIntosh db75704bfc Fix 'repo cherry-pick' to avoid hanging on commit-msg update.
After performing the actual cherry-pick operation, the code
in cherry_pick.py opens a pipe to 'git commit -F' to rewrite the commit
message, emits the fixed-up commit msg to the pipe, then waits
for 'git commit' to complete. The child 'git' process winds up
hanging while reading from the pipe, however, since the parent
process still has it open. To fix the hang, change the parent process
to close its end of the pipe after it has emitted the message.

Change-Id: I5929371e69a5b076f09009d00d40a2c72ac8ac33
2015-06-22 08:00:20 -04:00

116 lines
3.4 KiB
Python

#
# Copyright (C) 2010 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import print_function
import re
import sys
from command import Command
from git_command import GitCommand
CHANGE_ID_RE = re.compile(r'^\s*Change-Id: I([0-9a-f]{40})\s*$')
class CherryPick(Command):
common = True
helpSummary = "Cherry-pick a change."
helpUsage = """
%prog <sha1>
"""
helpDescription = """
'%prog' cherry-picks a change from one branch to another.
The change id will be updated, and a reference to the old
change id will be added.
"""
def _Options(self, p):
pass
def Execute(self, opt, args):
if len(args) != 1:
self.Usage()
reference = args[0]
p = GitCommand(None,
['rev-parse', '--verify', reference],
capture_stdout = True,
capture_stderr = True)
if p.Wait() != 0:
print(p.stderr, file=sys.stderr)
sys.exit(1)
sha1 = p.stdout.strip()
p = GitCommand(None, ['cat-file', 'commit', sha1], capture_stdout=True)
if p.Wait() != 0:
print("error: Failed to retrieve old commit message", file=sys.stderr)
sys.exit(1)
old_msg = self._StripHeader(p.stdout)
p = GitCommand(None,
['cherry-pick', sha1],
capture_stdout = True,
capture_stderr = True)
status = p.Wait()
print(p.stdout, file=sys.stdout)
print(p.stderr, file=sys.stderr)
if status == 0:
# The cherry-pick was applied correctly. We just need to edit the
# commit message.
new_msg = self._Reformat(old_msg, sha1)
p = GitCommand(None, ['commit', '--amend', '-F', '-'],
provide_stdin = True,
capture_stdout = True,
capture_stderr = True)
p.stdin.write(new_msg)
p.stdin.close()
if p.Wait() != 0:
print("error: Failed to update commit message", file=sys.stderr)
sys.exit(1)
else:
print('NOTE: When committing (please see above) and editing the commit '
'message, please remove the old Change-Id-line and add:')
print(self._GetReference(sha1), file=sys.stderr)
print(file=sys.stderr)
def _IsChangeId(self, line):
return CHANGE_ID_RE.match(line)
def _GetReference(self, sha1):
return "(cherry picked from commit %s)" % sha1
def _StripHeader(self, commit_msg):
lines = commit_msg.splitlines()
return "\n".join(lines[lines.index("")+1:])
def _Reformat(self, old_msg, sha1):
new_msg = []
for line in old_msg.splitlines():
if not self._IsChangeId(line):
new_msg.append(line)
# Add a blank line between the message and the change id/reference
try:
if new_msg[-1].strip() != "":
new_msg.append("")
except IndexError:
pass
new_msg.append(self._GetReference(sha1))
return "\n".join(new_msg)