String result = StringUtil.join("→", "left", "right");
        assertEquals("left→right", result);
    }

    @Test
    @DisplayName("Should handle Unicode characters in elements")
    void testJoinWithUnicodeElements() {
        String result = StringUtil.join(",", "日本語", "中文", "한국어");
        assertEquals("日本語,中文,한국어", result);
    }

    @ParameterizedTest
    @DisplayName("Should handle various delimiter types")