tag = String.trim(tag),
{describe, 0} <- System.cmd("git", ["describe", "--tags", "--abbrev=8"]),
describe = String.trim(describe),
ahead <- String.replace(describe, tag, "") do
{String.replace_prefix(tag, "v", ""), if(ahead != "", do: String.trim(ahead))}
else
tag = String.trim(tag),
{describe, 0} <- System.cmd("git", ["describe", "--tags", "--abbrev=8"]),
describe = String.trim(describe),
ahead <- String.replace(describe, tag, "") do
{String.replace_prefix(tag, "v", ""), if(ahead != "", do: String.trim(ahead))}
else