LanguageTest.java

//usr/bin/env java -enableassertions --class-path ${APP_DIR:-.}/lib/'*' "$0" "$@"; exit $?

void main() {
    TestHelper.runTests(getClass());
}

void fromStringTest() {
    Optional<Language> optLanguage = Language.fromString("French");
    assert optLanguage.isPresent() : "No language returned";
    assert optLanguage.get().equals(Language.French) : "Incorrect language returned";
}

void frenchGreetTest() {
    String greet = Language.French.greet();
    assert greet.equals("Bonjour 🇫🇷") : "Incorrect greet returned";
}

void englishGreetTest() {
    String greet = Language.English.greet();
    assert greet.equals("Hello 🇬🇧") : "Incorrect greet returned";
}

void spanishGreetTest() {
    Language spanish = Arrays.stream(Language.values())
            .filter(language -> language.name().equals("Spanish"))
            .findFirst()
            .orElse(null);
    assert spanish == null : "Incorrect Language returned";
}