private static Optional getParentLocaleBasedOnFallback()

in locales-utils/src/main/java/com/spotify/i18n/locales/utils/hierarchy/LocalesHierarchyUtils.java [195:214]

• 15 lines of code
• 5 McCabe index (conditional complexity)

  private static Optional<ULocale> getParentLocaleBasedOnFallback(final ULocale locale) {
    if (isSameLocale(locale, ULocale.ROOT)) {
      return Optional.empty();
    } else if (isSameLocale(locale.getFallback(), ULocale.ROOT)) {
      return Optional.of(ULocale.ROOT);
    } else if (scriptIsMajorLanguageDifferentiator(locale)) {
      // When we know the script is a major differentiator, we assess the parent locale based on it.
      return getParentLocaleBasedOnLocaleAndScript(locale);
    } else {
      // When the script isn't a major differentiator, we can confidently return the fallback
      // property of the given locale as parent locale, as long as it doesn't contain any script
      // code. Otherwise, we assess the parent locale based on the locale script, to prevent
      // unavailable yet valid locales like es-Arab from being considered.
      if (locale.getScript().isEmpty()) {
        return Optional.of(locale.getFallback());
      } else {
        return getParentLocaleBasedOnLocaleAndScript(locale);
      }
    }
  }