#!/usr/bin/env python # Copyright 2017 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. """Splits a branch into smaller branches and uploads CLs.""" import collections import os import re import subprocess2 import sys import tempfile import git_footers import owners import owners_finder import git_common as git # If a call to `git cl split` will generate more than this number of CLs, the # command will prompt the user to make sure they know what they're doing. Large # numbers of CLs generated by `git cl split` have caused infrastructure issues # in the past. CL_SPLIT_FORCE_LIMIT = 10 def ReadFile(file_path): """Returns the content of |file_path|.""" with open(file_path) as f: content = f.read() return content def EnsureInGitRepository(): """Throws an exception if the current directory is not a git repository.""" git.run('rev-parse') def CreateBranchForDirectory(prefix, directory, upstream): """Creates a branch named |prefix| + "_" + |directory| + "_split". Return false if the branch already exists. |upstream| is used as upstream for the created branch. """ existing_branches = set(git.branches(use_limit = False)) branch_name = prefix + '_' + directory + '_split' if branch_name in existing_branches: return False git.run('checkout', '-t', upstream, '-b', branch_name) return True def FormatDescriptionOrComment(txt, directory): """Replaces $directory with |directory| in |txt|.""" return txt.replace('$directory', '/' + directory) def AddUploadedByGitClSplitToDescription(description): """Adds a 'This CL was uploaded by git cl split.' line to |description|. The line is added before footers, or at the end of |description| if it has no footers. """ split_footers = git_footers.split_footers(description) lines = split_footers[0] if not lines[-1] or lines[-1].isspace(): lines = lines + [''] lines = lines + ['This CL was uploaded by git cl split.'] if split_footers[1]: lines += [''] + split_footers[1] return '\n'.join(lines) def UploadCl(refactor_branch, refactor_branch_upstream, directory, files, description, comment, reviewers, changelist, cmd_upload, cq_dry_run): """Uploads a CL with all changes to |files| in |refactor_branch|. Args: refactor_branch: Name of the branch that contains the changes to upload. refactor_branch_upstream: Name of the upstream of |refactor_branch|. directory: Path to the directory that contains the OWNERS file for which to upload a CL. files: List of AffectedFile instances to include in the uploaded CL. description: Description of the uploaded CL. comment: Comment to post on the uploaded CL. reviewers: A set of reviewers for the CL. changelist: The Changelist class. cmd_upload: The function associated with the git cl upload command. cq_dry_run: If CL uploads should also do a cq dry run. """ # Create a branch. if not CreateBranchForDirectory( refactor_branch, directory, refactor_branch_upstream): print 'Skipping ' + directory + ' for which a branch already exists.' return # Checkout all changes to files in |files|. deleted_files = [f.AbsoluteLocalPath() for f in files if f.Action() == 'D'] if deleted_files: git.run(*['rm'] + deleted_files) modified_files = [f.AbsoluteLocalPath() for f in files if f.Action() != 'D'] if modified_files: git.run(*['checkout', refactor_branch, '--'] + modified_files) # Commit changes. The temporary file is created with delete=False so that it # can be deleted manually after git has read it rather than automatically # when it is closed. with tempfile.NamedTemporaryFile(delete=False) as tmp_file: tmp_file.write(FormatDescriptionOrComment(description, directory)) # Close the file to let git open it at the next line. tmp_file.close() git.run('commit', '-F', tmp_file.name) os.remove(tmp_file.name) # Upload a CL. upload_args = ['-f', '-r', ','.join(reviewers)] if cq_dry_run: upload_args.append('--cq-dry-run') if not comment: upload_args.append('--send-mail') print 'Uploading CL for ' + directory + '.' cmd_upload(upload_args) if comment: changelist().AddComment(FormatDescriptionOrComment(comment, directory), publish=True) def GetFilesSplitByOwners(owners_database, files): """Returns a map of files split by OWNERS file. Returns: A map where keys are paths to directories containing an OWNERS file and values are lists of files sharing an OWNERS file. """ files_split_by_owners = collections.defaultdict(list) for f in files: files_split_by_owners[owners_database.enclosing_dir_with_owners( f.LocalPath())].append(f) return files_split_by_owners def PrintClInfo(cl_index, num_cls, directory, file_paths, description, reviewers): """Prints info about a CL. Args: cl_index: The index of this CL in the list of CLs to upload. num_cls: The total number of CLs that will be uploaded. directory: Path to the directory that contains the OWNERS file for which to upload a CL. file_paths: A list of files in this CL. description: The CL description. reviewers: A set of reviewers for this CL. """ description_lines = FormatDescriptionOrComment(description, directory).splitlines() indented_description = '\n'.join([' ' + l for l in description_lines]) print 'CL {}/{}'.format(cl_index, num_cls) print 'Path: {}'.format(directory) print 'Reviewers: {}'.format(', '.join(reviewers)) print '\n' + indented_description + '\n' print '\n'.join(file_paths) print def SplitCl(description_file, comment_file, changelist, cmd_upload, dry_run, cq_dry_run): """"Splits a branch into smaller branches and uploads CLs. Args: description_file: File containing the description of uploaded CLs. comment_file: File containing the comment of uploaded CLs. changelist: The Changelist class. cmd_upload: The function associated with the git cl upload command. dry_run: Whether this is a dry run (no branches or CLs created). cq_dry_run: If CL uploads should also do a cq dry run. Returns: 0 in case of success. 1 in case of error. """ description = AddUploadedByGitClSplitToDescription(ReadFile(description_file)) comment = ReadFile(comment_file) if comment_file else None try: EnsureInGitRepository() cl = changelist() change = cl.GetChange(cl.GetCommonAncestorWithUpstream(), None) files = change.AffectedFiles() if not files: print 'Cannot split an empty CL.' return 1 author = git.run('config', 'user.email').strip() or None refactor_branch = git.current_branch() assert refactor_branch, "Can't run from detached branch." refactor_branch_upstream = git.upstream(refactor_branch) assert refactor_branch_upstream, \ "Branch %s must have an upstream." % refactor_branch owners_database = owners.Database(change.RepositoryRoot(), file, os.path) owners_database.load_data_needed_for([f.LocalPath() for f in files]) files_split_by_owners = GetFilesSplitByOwners(owners_database, files) num_cls = len(files_split_by_owners) print('Will split current branch (' + refactor_branch + ') into ' + str(num_cls) + ' CLs.\n') if cq_dry_run and num_cls > CL_SPLIT_FORCE_LIMIT: print ( 'This will generate "%r" CLs. This many CLs can potentially generate' ' too much load on the build infrastructure. Please email' ' infra-dev@chromium.org to ensure that this won\'t break anything.' ' The infra team reserves the right to cancel your jobs if they are' ' overloading the CQ.') % num_cls answer = raw_input('Proceed? (y/n):') if answer.lower() != 'y': return 0 for cl_index, (directory, files) in \ enumerate(files_split_by_owners.iteritems(), 1): # Use '/' as a path separator in the branch name and the CL description # and comment. directory = directory.replace(os.path.sep, '/') file_paths = [f.LocalPath() for f in files] reviewers = owners_database.reviewers_for(file_paths, author) if dry_run: PrintClInfo(cl_index, num_cls, directory, file_paths, description, reviewers) else: UploadCl(refactor_branch, refactor_branch_upstream, directory, files, description, comment, reviewers, changelist, cmd_upload, cq_dry_run) # Go back to the original branch. git.run('checkout', refactor_branch) except subprocess2.CalledProcessError as cpe: sys.stderr.write(cpe.stderr) return 1 return 0