public String toOriginalString(boolean includeQualifier, boolean includeSnapshot) {
    StringBuilder sb = new StringBuilder();
    sb.append(major);
    if (versionFields > 1) {
      sb.append('.').append(minor);
      if (versionFields > 2) {
        sb.append('.').append(micro);
      }
    }
    if (includeQualifier && qualifier != null) {
      sb.append(qualifier);
    }
    if (includeSnapshot && isSnapshot) {
      sb.append("-SNAPSHOT");
    }
    return sb.toString();
  }
A version number with format major.minor.micro-qualifier.
spock-core/src/main/java/org/spockframework/util/VersionNumber.java