diff options
Diffstat (limited to 'llvm_tools/revert_checker.py')
| -rwxr-xr-x | llvm_tools/revert_checker.py | 97 |
1 files changed, 63 insertions, 34 deletions
diff --git a/llvm_tools/revert_checker.py b/llvm_tools/revert_checker.py index bb9182b0..acc8b5fa 100755 --- a/llvm_tools/revert_checker.py +++ b/llvm_tools/revert_checker.py @@ -1,8 +1,17 @@ #!/usr/bin/env python3 # -*- coding: utf-8 -*- -# Copyright 2020 The Chromium OS Authors. All rights reserved. -# Use of this source code is governed by a BSD-style license that can be -# found in the LICENSE file. +#===----------------------------------------------------------------------===## +# +# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +# See https://llvm.org/LICENSE.txt for license information. +# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +# +#===----------------------------------------------------------------------===## +# +# !!!!!!!!!!!! NOTE !!!!!!!!!!!! +# This is copied directly from upstream LLVM. Please make any changes upstream, +# rather than to this file directly. Once changes are made there, you're free +# to integrate them here. """Checks for reverts of commits across a given git commit. @@ -20,11 +29,21 @@ conflicts/etc always introduce _some_ amount of fuzziness. This script just uses a bundle of heuristics, and is bound to ignore / incorrectly flag some reverts. The hope is that it'll easily catch the vast majority (>90%) of them, though. -""" -# pylint: disable=cros-logging-import +This is designed to be used in one of two ways: an import in Python, or run +directly from a shell. If you want to import this, the `find_reverts` +function is the thing to look at. If you'd rather use this from a shell, have a +usage example: + +``` +./revert_checker.py c47f97169 origin/main origin/release/12.x +``` -from __future__ import print_function +This checks for all reverts from the tip of origin/main to c47f97169, which are +across the latter. It then does the same for origin/release/12.x to c47f97169. +Duplicate reverts discovered when walking both roots (origin/main and +origin/release/12.x) are deduplicated in output. +""" import argparse import collections @@ -32,7 +51,9 @@ import logging import re import subprocess import sys -import typing as t +from typing import Generator, List, NamedTuple, Iterable + +assert sys.version_info >= (3, 6), 'Only Python 3.6+ is supported.' # People are creative with their reverts, and heuristics are a bit difficult. # Like 90% of of reverts have "This reverts commit ${full_sha}". @@ -43,7 +64,7 @@ import typing as t # starts involving human intervention, which is probably not worth it for now. -def _try_parse_reverts_from_commit_message(commit_message: str) -> t.List[str]: +def _try_parse_reverts_from_commit_message(commit_message: str) -> List[str]: if not commit_message: return [] @@ -56,9 +77,10 @@ def _try_parse_reverts_from_commit_message(commit_message: str) -> t.List[str]: return results -def _stream_stdout(command: t.List[str]) -> t.Generator[str, None, None]: +def _stream_stdout(command: List[str]) -> Generator[str, None, None]: with subprocess.Popen( command, stdout=subprocess.PIPE, encoding='utf-8', errors='replace') as p: + assert p.stdout is not None # for mypy's happiness. yield from p.stdout @@ -73,14 +95,14 @@ def _resolve_sha(git_dir: str, sha: str) -> str: ).strip() -_LogEntry = t.NamedTuple('_LogEntry', [ +_LogEntry = NamedTuple('_LogEntry', [ ('sha', str), - ('commit_message', t.List[str]), + ('commit_message', str), ]) def _log_stream(git_dir: str, root_sha: str, - end_at_sha: str) -> t.Iterable[_LogEntry]: + end_at_sha: str) -> Iterable[_LogEntry]: sep = 50 * '<>' log_command = [ 'git', @@ -103,8 +125,6 @@ def _log_stream(git_dir: str, root_sha: str, break while found_commit_header: - # crbug.com/1041148 - # pylint: disable=stop-iteration-return sha = next(stdout_stream, None) assert sha is not None, 'git died?' sha = sha.rstrip() @@ -122,52 +142,54 @@ def _log_stream(git_dir: str, root_sha: str, yield _LogEntry(sha, '\n'.join(commit_message).rstrip()) -def _shas_between(git_dir: str, base_ref: str, - head_ref: str) -> t.Iterable[str]: +def _shas_between(git_dir: str, base_ref: str, head_ref: str) -> Iterable[str]: rev_list = [ 'git', '-C', git_dir, 'rev-list', '--first-parent', - '%s..%s' % (base_ref, head_ref), + f'{base_ref}..{head_ref}', ] return (x.strip() for x in _stream_stdout(rev_list)) def _rev_parse(git_dir: str, ref: str) -> str: - result = subprocess.check_output( + return subprocess.check_output( ['git', '-C', git_dir, 'rev-parse', ref], encoding='utf-8', ).strip() - return t.cast(str, result) -Revert = t.NamedTuple('Revert', [ +Revert = NamedTuple('Revert', [ ('sha', str), ('reverted_sha', str), ]) -def find_common_parent_commit(git_dir: str, ref_a: str, ref_b: str) -> str: +def _find_common_parent_commit(git_dir: str, ref_a: str, ref_b: str) -> str: + """Finds the closest common parent commit between `ref_a` and `ref_b`.""" return subprocess.check_output( ['git', '-C', git_dir, 'merge-base', ref_a, ref_b], encoding='utf-8', ).strip() -def find_reverts(git_dir: str, across_ref: str, root: str) -> t.List[Revert]: - """Finds reverts across `across_ref` in `git_dir`, starting from `root`.""" +def find_reverts(git_dir: str, across_ref: str, root: str) -> List[Revert]: + """Finds reverts across `across_ref` in `git_dir`, starting from `root`. + + These reverts are returned in order of oldest reverts first. + """ across_sha = _rev_parse(git_dir, across_ref) root_sha = _rev_parse(git_dir, root) - common_ancestor = find_common_parent_commit(git_dir, across_sha, root_sha) + common_ancestor = _find_common_parent_commit(git_dir, across_sha, root_sha) if common_ancestor != across_sha: - raise ValueError("%s isn't an ancestor of %s (common ancestor: %s)" % - (across_sha, root_sha, common_ancestor)) + raise ValueError(f"{across_sha} isn't an ancestor of {root_sha} " + '(common ancestor: {common_ancestor})') intermediate_commits = set(_shas_between(git_dir, across_sha, root_sha)) - assert across_ref not in intermediate_commits + assert across_sha not in intermediate_commits logging.debug('%d commits appear between %s and %s', len(intermediate_commits), across_sha, root_sha) @@ -204,10 +226,14 @@ def find_reverts(git_dir: str, across_ref: str, root: str) -> t.List[Revert]: logging.error("%s claims to revert %s -- which isn't a commit -- %s", sha, object_type, reverted_sha) + # Since `all_reverts` contains reverts in log order (e.g., newer comes before + # older), we need to reverse this to keep with our guarantee of older = + # earlier in the result. + all_reverts.reverse() return all_reverts -def main(args: t.List[str]) -> int: +def _main() -> None: parser = argparse.ArgumentParser( description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter) parser.add_argument( @@ -217,7 +243,7 @@ def main(args: t.List[str]) -> int: parser.add_argument( 'root', nargs='+', help='Root(s) to search for commits from.') parser.add_argument('--debug', action='store_true') - opts = parser.parse_args(args) + opts = parser.parse_args() logging.basicConfig( format='%(asctime)s: %(levelname)s: %(filename)s:%(lineno)d: %(message)s', @@ -228,14 +254,17 @@ def main(args: t.List[str]) -> int: # out. The overwhelmingly common case is also to have one root, and it's way # easier to reason about output that comes in an order that's meaningful to # git. - all_reverts = collections.OrderedDict() + seen_reverts = set() + all_reverts = [] for root in opts.root: for revert in find_reverts(opts.git_dir, opts.base_ref, root): - all_reverts[revert] = None + if revert not in seen_reverts: + seen_reverts.add(revert) + all_reverts.append(revert) - for revert in all_reverts.keys(): - print('%s claims to revert %s' % (revert.sha, revert.reverted_sha)) + for revert in all_reverts: + print(f'{revert.sha} claims to revert {revert.reverted_sha}') if __name__ == '__main__': - sys.exit(main(sys.argv[1:])) + _main() |