getMergeBase method
Resolves the common ancestor commit SHA between baseRef and HEAD.
Implementation
Future<String> getMergeBase(String baseRef) async {
final res = await _runGit(['merge-base', baseRef, 'HEAD']);
if (res.exitCode != 0) {
throw ArgumentError(
'Failed to resolve merge base for "$baseRef": '
'${(res.stderr as String).trim()}',
);
}
return (res.stdout as String).trim();
}