#!/usr/bin/env python # coding: utf-8 # 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. import argparse import os import re import subprocess import sys import tempfile import textwrap IS_WINDOWS = sys.platform.startswith('win') def SubprocessCheckCall0Or1(args): """Like subprocss.check_call(), but allows a return code of 1. Returns True if the subprocess exits with code 0, False if it exits with code 1, and re-raises the subprocess.check_call() exception otherwise. """ try: subprocess.check_call(args, shell=IS_WINDOWS) except subprocess.CalledProcessError, e: if e.returncode != 1: raise return False return True def GitMergeBaseIsAncestor(ancestor, descendant): """Determines whether |ancestor| is an ancestor of |descendant|. """ return SubprocessCheckCall0Or1( ['git', 'merge-base', '--is-ancestor', ancestor, descendant]) def main(args): parser = argparse.ArgumentParser( description='Update the in-tree copy of an imported project') parser.add_argument( '--repository', default='https://chromium.googlesource.com/crashpad/crashpad', help='The imported project\'s remote fetch URL', metavar='URL') parser.add_argument( '--subtree', default='third_party/crashpad/crashpad', help='The imported project\'s location in this project\'s tree', metavar='PATH') parser.add_argument( '--update-to', default='FETCH_HEAD', help='What to update the imported project to', metavar='COMMITISH') parser.add_argument( '--fetch-ref', default='HEAD', help='The remote ref to fetch', metavar='REF') parser.add_argument( '--readme', help='The README.chromium file describing the imported project', metavar='FILE', dest='readme_path') parsed = parser.parse_args(args) original_head = ( subprocess.check_output(['git', 'rev-parse', 'HEAD'], shell=IS_WINDOWS).rstrip()) # Read the README, because that’s what it’s for. Extract some things from # it, and save it to be able to update it later. readme_path = (parsed.readme_path or os.path.join(os.path.dirname(__file__ or '.'), 'README.chromium')) readme_content_old = open(readme_path).read() project_name_match = re.search( r'^Name:\s+(.*)$', readme_content_old, re.MULTILINE) project_name = project_name_match.group(1) # Extract the original commit hash from the README. revision_match = re.search(r'^Revision:\s+([0-9a-fA-F]{40})($|\s)', readme_content_old, re.MULTILINE) revision_old = revision_match.group(1) subprocess.check_call(['git', 'fetch', parsed.repository, parsed.fetch_ref], shell=IS_WINDOWS) # Make sure that parsed.update_to is an ancestor of FETCH_HEAD, and # revision_old is an ancestor of parsed.update_to. This prevents the use of # hashes that are known to git but that don’t make sense in the context of # the update operation. if not GitMergeBaseIsAncestor(parsed.update_to, 'FETCH_HEAD'): raise Exception('update_to is not an ancestor of FETCH_HEAD', parsed.update_to, 'FETCH_HEAD') if not GitMergeBaseIsAncestor(revision_old, parsed.update_to): raise Exception('revision_old is not an ancestor of update_to', revision_old, parsed.update_to) update_range = revision_old + '..' + parsed.update_to # This cherry-picks each change in the window from the upstream project into # the current branch. assisted_cherry_pick = False try: if not SubprocessCheckCall0Or1(['git', 'cherry-pick', '--keep-redundant-commits', '--strategy=subtree', '-Xsubtree=' + parsed.subtree, '-x', update_range]): assisted_cherry_pick = True print >>sys.stderr, (""" Please fix the errors above and run "git cherry-pick --continue". Press Enter when "git cherry-pick" completes. You may use a new shell for this, or ^Z if job control is available. Press ^C to abort. """) raw_input() except: # ^C, signal, or something else. print >>sys.stderr, 'Aborting...' subprocess.call(['git', 'cherry-pick', '--abort'], shell=IS_WINDOWS) raise # Get an abbreviated hash and subject line for each commit in the window, # sorted in chronological order. log_lines = subprocess.check_output(['git', '-c', 'core.abbrev=12', 'log', '--abbrev-commit', '--pretty=oneline', '--reverse', update_range], shell=IS_WINDOWS).splitlines(False) if assisted_cherry_pick: # If the user had to help, count the number of cherry-picked commits, # expecting it to match. cherry_picked_commits = int(subprocess.check_output( ['git', 'rev-list', '--count', original_head + '..HEAD'])) if cherry_picked_commits != len(log_lines): print >>sys.stderr, 'Something smells fishy, aborting anyway...' subprocess.call(['git', 'cherry-pick', '--abort'], shell=IS_WINDOWS) raise Exception('not all commits were cherry-picked', len(log_lines), cherry_picked_commits) # Make a nice commit message. Start with the full commit hash. revision_new = subprocess.check_output( ['git', 'rev-parse', parsed.update_to], shell=IS_WINDOWS).rstrip() new_message = 'Update ' + project_name + ' to ' + revision_new + '\n\n' # Wrap everything to 72 characters, with a hanging indent. wrapper = textwrap.TextWrapper(width=72, subsequent_indent = ' ' * 13) for line in log_lines: # Strip trailing periods from subjects. if line.endswith('.'): line = line[:-1] # If any subjects have what look like commit hashes in them, truncate # them to 12 characters. line = re.sub(r'(\s)([0-9a-fA-F]{12})([0-9a-fA-F]{28})($|\s)', r'\1\2\4', line) new_message += '\n'.join(wrapper.wrap(line)) + '\n' # Update the README with the new hash. readme_content_new = re.sub( r'^(Revision:\s+)([0-9a-fA-F]{40})($|\s.*?$)', r'\g<1>' + revision_new, readme_content_old, 1, re.MULTILINE) # If the in-tree copy has no changes relative to the upstream, clear the # “Local Modifications” section of the README. has_local_modifications = True if SubprocessCheckCall0Or1(['git', 'diff-tree', '--quiet', parsed.update_to, 'HEAD:' + parsed.subtree]): has_local_modifications = False readme_content_new = re.sub(r'\nLocal Modifications:\n.*$', '\nLocal Modifications:\nNone.', readme_content_new, 1) # This soft-reset causes all of the cherry-picks to show up as staged, # which will have the effect of squashing them along with the README update # when committed below. subprocess.check_call(['git', 'reset', '--soft', original_head], shell=IS_WINDOWS) # Write the new README. open(readme_path, 'wb').write(readme_content_new) # Commit everything. subprocess.check_call(['git', 'add', readme_path], shell=IS_WINDOWS) try: commit_message_name = None with tempfile.NamedTemporaryFile(delete=False) as commit_message_f: commit_message_name = commit_message_f.name commit_message_f.write(new_message) subprocess.check_call(['git', 'commit', '--file=' + commit_message_name], shell=IS_WINDOWS) finally: if commit_message_name: os.unlink(commit_message_name) if has_local_modifications: print >>sys.stderr, ( 'Remember to check the Local Modifications section in ' + readme_path) return 0 if __name__ == '__main__': sys.exit(main(sys.argv[1:]))