runbot/runbot_merge/git.py
Xavier Morel 6a1b77b92c [ADD] runbot_merge: support for unstaged patches
Unstaged changes can be useful or necessary for some tasks
e.g. absolute emergency (where even faking the state of a staging is
not really desirable, if that's even possible anymore), or changes
which are so broad they're difficult to stage (e.g. t10s updates).

Add a new object which serves as a queue for patch to direct-apply,
with support for either text patches (udiff style out of git show or
format-patch) or commits to cherry-pick. In the former case, the part
of the show / format-patch before the diff itself is used for the
commit metadata (author, committer, dates, message) whereas for the
commit version the commit itself is reused as-is.

Applied patches are simply disabled for traceability.

Fixes #926
2024-10-03 12:06:00 +02:00

321 lines
12 KiB
Python

import dataclasses
import itertools
import logging
import os
import pathlib
import resource
import stat
import subprocess
from operator import methodcaller
from typing import Optional, TypeVar, Union, Sequence, Tuple, Dict
from collections.abc import Iterable, Mapping, Callable
from odoo.tools.appdirs import user_cache_dir
from .github import MergeError, PrCommit
_logger = logging.getLogger(__name__)
def source_url(repository) -> str:
return 'https://{}@github.com/{}'.format(
repository.project_id.github_token,
repository.name,
)
def fw_url(repository) -> str:
return 'https://{}@github.com/{}'.format(
repository.project_id.fp_github_token,
repository.fp_remote_target,
)
Authorship = Union[Tuple[str, str], Tuple[str, str, str]]
def get_local(repository, *, clone: bool = True) -> 'Optional[Repo]':
repos_dir = pathlib.Path(user_cache_dir('mergebot'))
repos_dir.mkdir(parents=True, exist_ok=True)
# NB: `repository.name` is `$org/$name` so this will be a subdirectory, probably
repo_dir = repos_dir / repository.name
if repo_dir.is_dir():
return git(repo_dir)
elif clone:
_logger.info("Cloning out %s to %s", repository.name, repo_dir)
subprocess.run(['git', 'clone', '--bare', source_url(repository), str(repo_dir)], check=True)
# bare repos don't have fetch specs by default, and fetching *into*
# them is a pain in the ass, configure fetch specs so `git fetch`
# works properly
repo = git(repo_dir)
repo.config('--add', 'remote.origin.fetch', '+refs/heads/*:refs/heads/*')
# negative refspecs require git 2.29
repo.config('--add', 'remote.origin.fetch', '^refs/heads/tmp.*')
repo.config('--add', 'remote.origin.fetch', '^refs/heads/staging.*')
return repo
else:
_logger.warning(
"Unable to acquire %s: %s",
repo_dir,
"doesn't exist" if not repo_dir.exists()\
else oct(stat.S_IFMT(repo_dir.stat().st_mode))
)
return None
ALWAYS = ('gc.auto=0', 'maintenance.auto=0')
def _bypass_limits():
resource.setrlimit(resource.RLIMIT_AS, (resource.RLIM_INFINITY, resource.RLIM_INFINITY))
def git(directory: str) -> 'Repo':
return Repo(directory, check=True)
Self = TypeVar("Self", bound="Repo")
class Repo:
def __init__(self, directory, **config) -> None:
self._directory = str(directory)
config.setdefault('stderr', subprocess.PIPE)
self._config = config
self._params = ()
self.runner = subprocess.run
def __getattr__(self, name: str) -> 'GitCommand':
return GitCommand(self, name.replace('_', '-'))
def _run(self, *args, **kwargs) -> subprocess.CompletedProcess:
opts = {**self._config, **kwargs}
args = ('git', '-C', self._directory)\
+ tuple(itertools.chain.from_iterable(('-c', p) for p in self._params + ALWAYS))\
+ args
try:
return self.runner(args, preexec_fn=_bypass_limits, **opts)
except subprocess.CalledProcessError as e:
stream = e.stderr or e.stdout
if stream:
_logger.error("git call error: %s", stream)
raise
def stdout(self, flag: bool = True) -> Self:
if flag is True:
return self.with_config(stdout=subprocess.PIPE)
elif flag is False:
return self.with_config(stdout=None)
return self.with_config(stdout=flag)
def check(self, flag: bool) -> Self:
return self.with_config(check=flag)
def with_config(self, **kw) -> Self:
opts = {**self._config, **kw}
r = Repo(self._directory, **opts)
r._params = self._params
return r
def with_params(self, *args) -> Self:
r = self.with_config()
r._params = args
return r
def clone(self, to: str, branch: Optional[str] = None) -> Self:
self._run(
'clone',
*([] if branch is None else ['-b', branch]),
self._directory, to,
)
return Repo(to)
def get_tree(self, commit_hash: str) -> str:
r = self.with_config(check=True).rev_parse(f'{commit_hash}^{{tree}}')
return r.stdout.strip()
def rebase(self, dest: str, commits: Sequence[PrCommit]) -> Tuple[str, Dict[str, str]]:
"""Implements rebase by hand atop plumbing so:
- we can work without a working copy
- we can track individual commits (and store the mapping)
It looks like `--merge-base` is not sufficient for `merge-tree` to
correctly keep track of history, so it loses contents. Therefore
implement in two passes as in the github version.
"""
repo = self.stdout().with_config(text=True, check=False)
logger = _logger.getChild('rebase')
if not commits:
raise MergeError("PR has no commits")
prev_tree = repo.get_tree(dest)
prev_original_tree = repo.get_tree(commits[0]['parents'][0]["sha"])
new_trees = []
parent = dest
for original in commits:
if len(original['parents']) != 1:
raise MergeError(
f"commits with multiple parents ({original['sha']}) can not be rebased, "
"either fix the branch to remove merges or merge without "
"rebasing")
new_trees.append(check(repo.merge_tree(parent, original['sha'])).stdout.strip())
# allow merging empty commits, but not empty*ing* commits while merging
if prev_original_tree != original['commit']['tree']['sha']:
if new_trees[-1] == prev_tree:
raise MergeError(
f"commit {original['sha']} results in an empty tree when "
f"merged, it is likely a duplicate of a merged commit, "
f"rebase and remove."
)
parent = check(repo.commit_tree(
tree=new_trees[-1],
parents=[parent, original['sha']],
message=f'temp rebase {original["sha"]}',
)).stdout.strip()
prev_tree = new_trees[-1]
prev_original_tree = original['commit']['tree']['sha']
mapping = {}
for original, tree in zip(commits, new_trees):
authorship = check(repo.show('--no-patch', '--pretty=%an%n%ae%n%ai%n%cn%n%ce', original['sha']))
author_name, author_email, author_date, committer_name, committer_email =\
authorship.stdout.splitlines()
c = check(repo.commit_tree(
tree=tree,
parents=[dest],
message=original['commit']['message'],
author=(author_name, author_email, author_date),
committer=(committer_name, committer_email),
)).stdout.strip()
logger.debug('copied %s to %s (parent: %s)', original['sha'], c, dest)
dest = mapping[original['sha']] = c
return dest, mapping
def merge(self, c1: str, c2: str, msg: str, *, author: Tuple[str, str]) -> str:
repo = self.stdout().with_config(text=True, check=False)
t = repo.merge_tree(c1, c2)
if t.returncode:
raise MergeError(t.stderr)
c = self.commit_tree(
tree=t.stdout.strip(),
message=msg,
parents=[c1, c2],
author=author,
)
if c.returncode:
raise MergeError(c.stderr)
return c.stdout.strip()
def commit_tree(
self, *, tree: str, message: str,
parents: Sequence[str] = (),
author: Optional[Authorship] = None,
committer: Optional[Authorship] = None,
) -> subprocess.CompletedProcess:
authorship = {}
if author:
authorship['GIT_AUTHOR_NAME'] = author[0]
authorship['GIT_AUTHOR_EMAIL'] = author[1]
if len(author) > 2:
authorship['GIT_AUTHOR_DATE'] = author[2]
if committer:
authorship['GIT_COMMITTER_NAME'] = committer[0]
authorship['GIT_COMMITTER_EMAIL'] = committer[1]
if len(committer) > 2:
authorship['GIT_COMMITTER_DATE'] = committer[2]
return self.with_config(
input=message,
stdout=subprocess.PIPE,
text=True,
env={
**os.environ,
**authorship,
# we don't want git to use the timezone of the machine it's
# running on: previously it used the timezone configured in
# github (?), which I think / assume defaults to a generic UTC
'TZ': 'UTC',
}
)._run(
'commit-tree',
tree,
'-F', '-',
*itertools.chain.from_iterable(('-p', p) for p in parents),
)
def update_tree(self, tree: str, files: Mapping[str, Callable[[Self, str], str]]) -> str:
# FIXME: either ignore or process binary files somehow (how does git show conflicts in binary files?)
repo = self.stdout().with_config(stderr=None, text=True, check=False, encoding="utf-8")
for f, c in files.items():
new_contents = c(repo, f)
oid = repo \
.with_config(input=new_contents) \
.hash_object("-w", "--stdin", "--path", f) \
.stdout.strip()
# we need to rewrite every tree from the parent of `f`
while f:
f, _, local = f.rpartition("/")
# tree to update, `{tree}:` works as an alias for tree
lstree = repo.ls_tree(f"{tree}:{f}").stdout.splitlines(keepends=False)
new_tree = "".join(
# tab before name is critical to the format
f"{mode} {typ} {oid if name == local else sha}\t{name}\n"
for mode, typ, sha, name in map(methodcaller("split", None, 3), lstree)
)
oid = repo.with_config(input=new_tree, check=True).mktree().stdout.strip()
tree = oid
return tree
def modify_delete(self, tree: str, files: Iterable[str]) -> str:
"""Updates ``files`` in ``tree`` to add conflict markers to show them
as being modify/delete-ed, rather than have only the original content.
This is because having just content in a valid file is easy to miss,
causing file resurrections as they get committed rather than re-removed.
TODO: maybe extract the diff information compared to before they were removed? idk
"""
def rewriter(r: Self, f: str) -> str:
contents = r.cat_file("-p", f"{tree}:{f}").stdout
return f"""\
<<<\x3c<<< HEAD
||||||| MERGE BASE
=======
{contents}
>>>\x3e>>> FORWARD PORTED
"""
return self.update_tree(tree, dict.fromkeys(files, rewriter))
def check(p: subprocess.CompletedProcess) -> subprocess.CompletedProcess:
if not p.returncode:
return p
_logger.info("rebase failed at %s\nstdout:\n%s\nstderr:\n%s", p.args, p.stdout, p.stderr)
raise MergeError(p.stderr or 'merge conflict')
@dataclasses.dataclass
class GitCommand:
repo: Repo
name: str
def __call__(self, *args, **kwargs) -> subprocess.CompletedProcess:
return self.repo._run(self.name, *args, *self._to_options(kwargs))
def _to_options(self, d):
for k, v in d.items():
if len(k) == 1:
yield '-' + k
else:
yield '--' + k.replace('_', '-')
if v not in (None, True):
assert v is not False
yield str(v)