# Copyright (c) 2012 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.
"""SCM-specific utility classes."""
from collections import defaultdict
import os
import pathlib
import platform
import re
from typing import Mapping, List
import gclient_utils
import git_common
import subprocess2
# TODO: Should fix these warnings.
# pylint: disable=line-too-long
# constants used to identify the tree state of a directory.
VERSIONED_NO = 0
VERSIONED_DIR = 1
VERSIONED_SUBMODULE = 2
def determine_scm(root):
"""Similar to upload.py's version but much simpler.
Returns 'git' or 'diff'.
"""
if os.path.isdir(os.path.join(root, '.git')):
return 'git'
try:
subprocess2.check_call(['git', 'rev-parse', '--show-cdup'],
stdout=subprocess2.DEVNULL,
stderr=subprocess2.DEVNULL,
cwd=root)
return 'git'
except (OSError, subprocess2.CalledProcessError):
return 'diff'
class GIT(object):
current_version = None
rev_parse_cache = {}
# Maps cwd -> {config key, [config values]}
# This cache speeds up all `git config ...` operations by only running a
# single subcommand, which can greatly accelerate things like
# git-map-branches.
_CONFIG_CACHE: Mapping[str, Mapping[str, List[str]]] = {}
@staticmethod
def _load_config(cwd: str) -> Mapping[str, List[str]]:
"""Loads git config for the given cwd.
The calls to this method are cached in-memory for performance. The
config is only reloaded on cache misses.
Args:
cwd: path to fetch `git config` for.
Returns:
A dict mapping git config keys to a list of its values.
"""
if cwd not in GIT._CONFIG_CACHE:
try:
rawConfig = GIT.Capture(['config', '--list', '-z'],
cwd=cwd,
strip_out=False)
except subprocess2.CalledProcessError:
return {}
cfg = defaultdict(list)
# Splitting by '\x00' gets an additional empty string at the end.
for line in rawConfig.split('\x00')[:-1]:
key, value = map(str.strip, line.split('\n', 1))
cfg[key].append(value)
GIT._CONFIG_CACHE[cwd] = cfg
return GIT._CONFIG_CACHE[cwd]
@staticmethod
def _clear_config(cwd: str) -> None:
GIT._CONFIG_CACHE.pop(cwd, None)
@staticmethod
def ApplyEnvVars(kwargs):
env = kwargs.pop('env', None) or os.environ.copy()
# Don't prompt for passwords; just fail quickly and noisily.
# By default, git will use an interactive terminal prompt when a
# username/ password is needed. That shouldn't happen in the chromium
# workflow, and if it does, then gclient may hide the prompt in the
# midst of a flood of terminal spew. The only indication that something
# has gone wrong will be when gclient hangs unresponsively. Instead, we
# disable the password prompt and simply allow git to fail noisily. The
# error message produced by git will be copied to gclient's output.
env.setdefault('GIT_ASKPASS', 'true')
env.setdefault('SSH_ASKPASS', 'true')
# 'cat' is a magical git string that disables pagers on all platforms.
env.setdefault('GIT_PAGER', 'cat')
return env
@staticmethod
def Capture(args, cwd=None, strip_out=True, **kwargs):
kwargs.setdefault('env', GIT.ApplyEnvVars(kwargs))
kwargs.setdefault('cwd', cwd)
kwargs.setdefault('autostrip', strip_out)
return git_common.run(*args, **kwargs)
@staticmethod
def CaptureStatus(cwd,
upstream_branch,
end_commit=None,
ignore_submodules=True):
# type: (str, str, Optional[str]) -> Sequence[Tuple[str, str]]
"""Returns git status.
Returns an array of (status, file) tuples."""
if end_commit is None:
end_commit = ''
if upstream_branch is None:
upstream_branch = GIT.GetUpstreamBranch(cwd)
if upstream_branch is None:
raise gclient_utils.Error('Cannot determine upstream branch')
command = [
'-c', 'core.quotePath=false', 'diff', '--name-status',
'--no-renames'
]
if ignore_submodules:
command.append('--ignore-submodules=all')
command.extend(['-r', '%s...%s' % (upstream_branch, end_commit)])
status = GIT.Capture(command, cwd)
results = []
if status:
for statusline in status.splitlines():
# 3-way merges can cause the status can be 'MMM' instead of 'M'.
# This can happen when the user has 2 local branches and he
# diffs between these 2 branches instead diffing to upstream.
m = re.match(r'^(\w)+\t(.+)$', statusline)
if not m:
raise gclient_utils.Error(
'status currently unsupported: %s' % statusline)
# Only grab the first letter.
results.append(('%s ' % m.group(1)[0], m.group(2)))
return results
@staticmethod
def GetConfig(cwd, key, default=None):
values = GIT._load_config(cwd).get(key, None)
if not values:
return default
return values[-1]
@staticmethod
def GetConfigBool(cwd, key) -> bool:
return GIT.GetConfig(cwd, key) == 'true'
@staticmethod
def GetConfigList(cwd, key):
return GIT._load_config(cwd).get(key, [])
@staticmethod
def YieldConfigRegexp(cwd, pattern):
"""Yields (key, value) pairs for any config keys matching `pattern`."""
p = re.compile(pattern)
for name, values in GIT._load_config(cwd).items():
if p.match(name):
for value in values:
yield name, value
@staticmethod
def GetBranchConfig(cwd, branch, key, default=None):
assert branch, 'A branch must be given'
key = 'branch.%s.%s' % (branch, key)
return GIT.GetConfig(cwd, key, default)
@staticmethod
def SetConfig(
cwd,
key,
value=None,
*,
append=False,
missing_ok=True,
modify_all=False,
scope='local',
value_pattern=None,
):
"""Sets or unsets one or more config values.
Args:
cwd: path to set `git config` for.
key: The specific config key to affect.
value: The value to set. If this is None, `key` will be unset.
append: If True and `value` is not None, this will append
the value instead of replacing an existing one.
missing_ok: If `value` is None (i.e. this is an unset operation),
ignore retcode=5 from `git config` (meaning that the value is
not present). If `value` is not None, then this option has no
effect.
modify_all: If True, this will change a set operation to
`--replace-all`, and will change an unset operation to
`--unset-all`.
scope: By default this is the local scope, but could be `system`,
`global`, or `worktree`, depending on which config scope you
want to affect.
value_pattern: For use with `modify_all=True`, allows
further filtering of the set or unset operation based on
the currently configured value. Ignored for
`modify_all=False`.
"""
GIT._clear_config(cwd)
args = ['config', f'--{scope}']
if value == None:
args.extend(['--unset' + ('-all' if modify_all else ''), key])
else:
if modify_all:
args.append('--replace-all')
if append:
args.append('--add')
args.extend([key, value])
if modify_all and value_pattern:
args.append(value_pattern)
accepted_retcodes = [0]
if value is None and missing_ok:
accepted_retcodes = [0, 5]
GIT.Capture(args, cwd=cwd, accepted_retcodes=accepted_retcodes)
@staticmethod
def SetBranchConfig(cwd, branch, key, value=None):
assert branch, 'A branch must be given'
key = 'branch.%s.%s' % (branch, key)
GIT.SetConfig(cwd, key, value)
@staticmethod
def ShortBranchName(branch):
"""Converts a name like 'refs/heads/foo' to just 'foo'."""
return branch.replace('refs/heads/', '')
@staticmethod
def GetBranchRef(cwd):
"""Returns the full branch reference, e.g. 'refs/heads/main'."""
try:
return GIT.Capture(['symbolic-ref', 'HEAD'], cwd=cwd)
except subprocess2.CalledProcessError:
return None
@staticmethod
def GetRemoteHeadRef(cwd, url, remote):
"""Returns the full default remote branch reference, e.g.
'refs/remotes/origin/main'."""
if os.path.exists(cwd):
try:
# Try using local git copy first
ref = 'refs/remotes/%s/HEAD' % remote
ref = GIT.Capture(['symbolic-ref', ref], cwd=cwd)
if not ref.endswith('master'):
return ref
except subprocess2.CalledProcessError:
pass
try:
# Check if there are changes in the default branch for this
# particular repository.
GIT.Capture(['remote', 'set-head', '-a', remote], cwd=cwd)
return GIT.Capture(['symbolic-ref', ref], cwd=cwd)
except subprocess2.CalledProcessError:
pass
try:
# Fetch information from git server
resp = GIT.Capture(['ls-remote', '--symref', url, 'HEAD'])
regex = r'^ref: (.*)\tHEAD$'
for line in resp.split('\n'):
m = re.match(regex, line)
if m:
return ''.join(GIT.RefToRemoteRef(m.group(1), remote))
except subprocess2.CalledProcessError:
pass
# Return default branch
return 'refs/remotes/%s/main' % remote
@staticmethod
def GetBranch(cwd):
"""Returns the short branch name, e.g. 'main'."""
branchref = GIT.GetBranchRef(cwd)
if branchref:
return GIT.ShortBranchName(branchref)
return None
@staticmethod
def GetRemoteBranches(cwd):
return GIT.Capture(['branch', '-r'], cwd=cwd).split()
@staticmethod
def FetchUpstreamTuple(cwd, branch=None):
"""Returns a tuple containing remote and remote ref,
e.g. 'origin', 'refs/heads/main'
"""
try:
branch = branch or GIT.GetBranch(cwd)
except subprocess2.CalledProcessError:
pass
if branch:
upstream_branch = GIT.GetBranchConfig(cwd, branch, 'merge')
if upstream_branch:
remote = GIT.GetBranchConfig(cwd, branch, 'remote', '.')
return remote, upstream_branch
upstream_branch = GIT.GetConfig(cwd, 'rietveld.upstream-branch')
if upstream_branch:
remote = GIT.GetConfig(cwd, 'rietveld.upstream-remote', '.')
return remote, upstream_branch
# Else, try to guess the origin remote.
remote_branches = GIT.GetRemoteBranches(cwd)
if 'origin/main' in remote_branches:
# Fall back on origin/main if it exits.
return 'origin', 'refs/heads/main'
if 'origin/master' in remote_branches:
# Fall back on origin/master if it exits.
return 'origin', 'refs/heads/master'
return None, None
@staticmethod
def RefToRemoteRef(ref, remote):
"""Convert a checkout ref to the equivalent remote ref.
Returns:
A tuple of the remote ref's (common prefix, unique suffix), or None if it
doesn't appear to refer to a remote ref (e.g. it's a commit hash).
"""
# TODO(mmoss): This is just a brute-force mapping based of the expected
# git config. It's a bit better than the even more brute-force
# replace('heads', ...), but could still be smarter (like maybe actually
# using values gleaned from the git config).
m = re.match('^(refs/(remotes/)?)?branch-heads/', ref or '')
if m:
return ('refs/remotes/branch-heads/', ref.replace(m.group(0), ''))
m = re.match('^((refs/)?remotes/)?%s/|(refs/)?heads/' % remote, ref
or '')
if m:
return ('refs/remotes/%s/' % remote, ref.replace(m.group(0), ''))
return None
@staticmethod
def RemoteRefToRef(ref, remote):
assert remote, 'A remote must be given'
if not ref or not ref.startswith('refs/'):
return None
if not ref.startswith('refs/remotes/'):
return ref
if ref.startswith('refs/remotes/branch-heads/'):
return 'refs' + ref[len('refs/remotes'):]
if ref.startswith('refs/remotes/%s/' % remote):
return 'refs/heads' + ref[len('refs/remotes/%s' % remote):]
return None
@staticmethod
def GetUpstreamBranch(cwd):
"""Gets the current branch's upstream branch."""
remote, upstream_branch = GIT.FetchUpstreamTuple(cwd)
if remote != '.' and upstream_branch:
remote_ref = GIT.RefToRemoteRef(upstream_branch, remote)
if remote_ref:
upstream_branch = ''.join(remote_ref)
return upstream_branch
@staticmethod
def IsAncestor(maybe_ancestor, ref, cwd=None):
# type: (string, string, Optional[string]) -> bool
"""Verifies if |maybe_ancestor| is an ancestor of |ref|."""
try:
GIT.Capture(['merge-base', '--is-ancestor', maybe_ancestor, ref],
cwd=cwd)
return True
except subprocess2.CalledProcessError:
return False
@staticmethod
def GetOldContents(cwd, filename, branch=None):
if not branch:
branch = GIT.GetUpstreamBranch(cwd)
if platform.system() == 'Windows':
# git show <sha>:<path> wants a posix path.
filename = filename.replace('\\', '/')
command = ['show', '%s:%s' % (branch, filename)]
try:
return GIT.Capture(command, cwd=cwd, strip_out=False)
except subprocess2.CalledProcessError:
return ''
@staticmethod
def GenerateDiff(cwd,
branch=None,
branch_head='HEAD',
full_move=False,
files=None):
"""Diffs against the upstream branch or optionally another branch.
full_move means that move or copy operations should completely recreate the
files, usually in the prospect to apply the patch for a try job."""
if not branch:
branch = GIT.GetUpstreamBranch(cwd)
command = [
'-c', 'core.quotePath=false', 'diff', '-p', '--no-color',
'--no-prefix', '--no-ext-diff', branch + "..." + branch_head
]
if full_move:
command.append('--no-renames')
else:
command.append('-C')
# TODO(maruel): --binary support.
if files:
command.append('--')
command.extend(files)
diff = GIT.Capture(command, cwd=cwd, strip_out=False).splitlines(True)
for i in range(len(diff)):
# In the case of added files, replace /dev/null with the path to the
# file being added.
if diff[i].startswith('--- /dev/null'):
diff[i] = '--- %s' % diff[i + 1][4:]
return ''.join(diff)
@staticmethod
def GetAllFiles(cwd):
"""Returns the list of all files under revision control."""
command = ['-c', 'core.quotePath=false', 'ls-files', '--', '.']
return GIT.Capture(command, cwd=cwd).splitlines(False)
@staticmethod
def GetSubmoduleCommits(cwd, submodules):
# type: (string, List[string]) => Mapping[string][string]
"""Returns a mapping of staged or committed new commits for submodules."""
if not submodules:
return {}
result = subprocess2.check_output(['git', 'ls-files', '-s', '--'] +
submodules,
cwd=cwd).decode('utf-8')
commit_hashes = {}
for r in result.splitlines():
# ['<mode>', '<commit_hash>', '<stage_number>', '<path>'].
record = r.strip().split(maxsplit=3) # path can contain spaces.
assert record[0] == '160000', 'file is not a gitlink: %s' % record
commit_hashes[record[3]] = record[1]
return commit_hashes
@staticmethod
def GetCheckoutRoot(cwd):
"""Returns the top level directory of a git checkout as an absolute path.
"""
root = GIT.Capture(['rev-parse', '--show-cdup'], cwd=cwd)
return os.path.abspath(os.path.join(cwd, root))
@staticmethod
def IsInsideWorkTree(cwd):
try:
return GIT.Capture(['rev-parse', '--is-inside-work-tree'], cwd=cwd)
except (OSError, subprocess2.CalledProcessError):
return False
@staticmethod
def IsVersioned(cwd, relative_dir):
# type: (str, str) -> int
"""Checks whether the given |relative_dir| is part of cwd's repo."""
output = GIT.Capture(['ls-tree', 'HEAD', '--', relative_dir], cwd=cwd)
if not output:
return VERSIONED_NO
if output.startswith('160000'):
return VERSIONED_SUBMODULE
return VERSIONED_DIR
@staticmethod
def ListSubmodules(repo_root):
# type: (str) -> Collection[str]
"""Returns the list of submodule paths for the given repo.
Path separators will be adjusted for the current OS.
"""
if not os.path.exists(os.path.join(repo_root, '.gitmodules')):
return []
config_output = GIT.Capture(
['config', '--file', '.gitmodules', '--get-regexp', 'path'],
cwd=repo_root)
return [
line.split()[-1].replace('/', os.path.sep)
for line in config_output.splitlines()
]
@staticmethod
def CleanupDir(cwd, relative_dir):
"""Cleans up untracked file inside |relative_dir|."""
return bool(GIT.Capture(['clean', '-df', relative_dir], cwd=cwd))
@staticmethod
def ResolveCommit(cwd, rev):
cache_key = None
# We do this instead of rev-parse --verify rev^{commit}, since on
# Windows git can be either an executable or batch script, each of which
# requires escaping the caret (^) a different way.
if gclient_utils.IsFullGitSha(rev):
# Only cache full SHAs
cache_key = hash(cwd + rev)
if val := GIT.rev_parse_cache.get(cache_key):
return val
# git-rev parse --verify FULL_GIT_SHA always succeeds, even if we
# don't have FULL_GIT_SHA locally. Removing the last character
# forces git to check if FULL_GIT_SHA refers to an object in the
# local database.
rev = rev[:-1]
res = GIT.Capture(['rev-parse', '--quiet', '--verify', rev], cwd=cwd)
if cache_key:
# We don't expect concurrent execution, so we don't lock anything.
GIT.rev_parse_cache[cache_key] = res
return res
@staticmethod
def IsValidRevision(cwd, rev, sha_only=False):
"""Verifies the revision is a proper git revision.
sha_only: Fail unless rev is a sha hash.
"""
try:
sha = GIT.ResolveCommit(cwd, rev)
except subprocess2.CalledProcessError:
return None
if sha_only:
return sha == rev.lower()
return True
class DIFF(object):
@staticmethod
def GetAllFiles(cwd):
"""Return all files under the repo at cwd.
If .gitmodules exists in cwd, use it to determine which folders are
submodules and don't recurse into them. Submodule paths are returned.
"""
# `git config --file` works outside of a git workspace.
submodules = GIT.ListSubmodules(cwd)
if not submodules:
return [
str(p.relative_to(cwd)) for p in pathlib.Path(cwd).rglob("*")
if p.is_file()
]
full_path_submodules = {os.path.join(cwd, s) for s in submodules}
def should_recurse(dirpath, dirname):
full_path = os.path.join(dirpath, dirname)
return full_path not in full_path_submodules
paths = list(full_path_submodules)
for dirpath, dirnames, filenames in os.walk(cwd):
paths.extend([os.path.join(dirpath, f) for f in filenames])
dirnames[:] = [d for d in dirnames if should_recurse(dirpath, d)]
return [os.path.relpath(p, cwd) for p in paths]