in lib/gitlab_git/diff.rb [22:42]
def between(repo, head, base, options = {}, *paths)
straight = options.delete(:straight) || false
common_commit = if straight
base
else
repo.merge_base_commit(head, base)
end
options ||= {}
actual_options = filter_diff_options(options)
repo.diff(common_commit, head, actual_options, *paths)
end