public void test_convertWithChi() {
        List<String> results = converter.convert("チ", null);
        assertTrue(results.contains("ti"));
        assertTrue(results.contains("chi"));
    }

    public void test_convertWithTsu() {
        List<String> results = converter.convert("ツ", null);
        assertTrue(results.contains("tu"));
        assertTrue(results.contains("tsu"));
    }

    public void test_convertWithFu() {