import subprocess
import sys
-from typing import Tuple
+from typing import Tuple, Union
import backoff
Repo = str # eg: "https://github.com/NixOS/nixpkgs.git"
Ref = str # eg: "master" or "v1.0.0"
Rev = str # eg: "53a27350551844e1ed1a9257690294767389ef0d"
+RefOrRev = Union[Ref, Rev]
def git_cachedir(repo: Repo) -> Path:
hashlib.sha256(repo.encode()).hexdigest()))
-def is_ancestor(repo: Repo, ref: Ref, rev: Rev) -> bool:
+def is_ancestor(repo: Repo, descendant: RefOrRev, ancestor: RefOrRev) -> bool:
cachedir = git_cachedir(repo)
- logging.debug('Checking if rev %s is an ancestor of ref "%s"', rev, ref)
- process = subprocess.run(
- ['git', '-C', cachedir, 'merge-base', '--is-ancestor', rev, ref], check=False)
+ logging.debug('Checking if %s is an ancestor of %s', ancestor, descendant)
+ process = subprocess.run(['git',
+ '-C',
+ cachedir,
+ 'merge-base',
+ '--is-ancestor',
+ ancestor,
+ descendant],
+ check=False)
return process.returncode == 0
-def verify_ancestry(repo: Repo, ref: Ref, rev: Rev) -> None:
- if not is_ancestor(repo, ref, rev):
- raise Exception('Rev %s is not an ancestor of ref "%s"' % (rev, ref))
+def verify_ancestry(
+ repo: Repo,
+ descendant: RefOrRev,
+ ancestor: RefOrRev) -> None:
+ if not is_ancestor(repo, descendant, ancestor):
+ raise Exception('%s is not an ancestor of %s' % (ancestor, descendant))
@backoff.on_exception(