String result = normalizer.normalize("ａｂｃ１２３ＸＹＺ", "field");

        assertEquals("abc123XYZ", result);
    }

    @Test
    public void test_nullInput() throws Exception {
        FullWidthToHalfWidthAlphabetNormalizer normalizer = new FullWidthToHalfWidthAlphabetNormalizer();

        String result = normalizer.normalize(null, "field");

    public void test_HalfwidthFullwidth() {
        ICUNormalizer normalizer = new ICUNormalizer("Halfwidth-Fullwidth");
        assertEquals("ケンサク", normalizer.normalize("ｹﾝｻｸ", null));
    }

    public void test_nullInput() {
        ICUNormalizer normalizer = new ICUNormalizer("Any-Lower");
        assertNull(normalizer.normalize(null, null));
    }

    public void test_nullTransliteratorId() {
        try {

        assertEquals('ｱ', HankakuKanaToZenkakuKana.mergeChar('ｱ', 'ﾟ'));
        assertEquals('ｶ', HankakuKanaToZenkakuKana.mergeChar('ｶ', 'a'));
    }

    @Test
    public void test_nullInput() throws Exception {
        HankakuKanaToZenkakuKana normalizer = new HankakuKanaToZenkakuKana();

        String result = normalizer.normalize(null, "field");

        assertEquals(null, result);
    }

        String result = chain.normalize("  TEST CASE  ", "field");

        assertEquals("test_case", result);
    }

    @Test
    public void test_nullInput() throws Exception {
        NormalizerChain chain = new NormalizerChain();
        chain.add(new FullWidthToHalfWidthAlphabetNormalizer());

        String result = chain.normalize(null, "field");

    assertThrows(IllegalArgumentException.class, () -> escapeAsString(SIMPLE_ESCAPER, test));
  }

  @SuppressWarnings("nullness") // test of bogus call
  public void testNullInput() {
    UnicodeEscaper e = SIMPLE_ESCAPER;
    assertThrows(NullPointerException.class, () -> e.escape((String) null));
  }

  public void testBadStrings() {
    UnicodeEscaper e = SIMPLE_ESCAPER;