in grp/grp.go [222:234]
func Contains(g InstanceGroup, account, region, cluster string) bool {
names, err := frigga.Parse(cluster)
if err != nil {
log.Printf("WARNING: could not parse cluster name: %s", cluster)
return false
}
return names.App == g.App() &&
string(account) == g.Account() &&
(AnyRegion(g) || string(region) == must(g.Region())) &&
(AnyStack(g) || names.Stack == must(g.Stack())) &&
(AnyCluster(g) || string(cluster) == must(g.Cluster()))
}