    @Test
    public void identityLanguagePivot() {

        LanguageIndex index = new LanguageIndex.Builder()
                .add(lp("it en"))
                .add(lp("en it"))
                .build(false);

        assertEquals(lpset("it en", "en it"), index.getLanguages());

        index = new LanguageIndex.Builder()
                .add(lp("it en"))
                .add(lp("en it"))
                .build(true);

        assertEquals(lpset("it en", "en it"), index.getLanguages());
    }