in tools/dockerversioning/versions/versions.go [137:148]
func validateUniqueTags(spec Spec) {
repoTags := make(map[string]bool)
for _, version := range spec.Versions {
for _, tag := range version.Tags {
repoTag := fmt.Sprintf("%s:%s", version.Repo, tag)
if repoTags[repoTag] {
log.Fatalf("error: duplicate repo tag %v", repoTag)
}
repoTags[repoTag] = true
}
}
}