// Get the expected result string
    String expected = "x[" + min + "][" + s1 + "][" + s2 + "][" + s3 + "][" + max + "]x";
    assertThat(escapeAsString(e, test)).isEqualTo(expected);
  }

  public void testTrailingHighSurrogate() {
    String test = "abc" + Character.MIN_HIGH_SURROGATE;
    assertThrows(IllegalArgumentException.class, () -> escapeAsString(NOP_ESCAPER, test));