'\ufdf0foo'      | _
        'foo\u0300'      | _
        'foo\u203f'      | _
    }

    def "identifies illegal character"() {
        expect:
        //	Char	   ::=   	#x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]
        //	/* any Unicode character, excluding the surrogate blocks, FFFE, and FFFF. */
        !XmlValidation.isLegalCharacter(character)

        where:

		x8 := byteorder.LeUint32(q[4*0x8:])
		x9 := byteorder.LeUint32(q[4*0x9:])
		xa := byteorder.LeUint32(q[4*0xa:])
		xb := byteorder.LeUint32(q[4*0xb:])
		xc := byteorder.LeUint32(q[4*0xc:])
		xd := byteorder.LeUint32(q[4*0xd:])
		xe := byteorder.LeUint32(q[4*0xe:])
		xf := byteorder.LeUint32(q[4*0xf:])

		// round 1
		a = b + bits.RotateLeft32((((c^d)&b)^d)+a+x0+0xd76aa478, 7)

   * (NCR). However, horizontal tab {@code '\t'}, line feed {@code '\n'} and carriage return {@code
   * '\r'} are escaped to a corresponding NCR {@code "	"}, {@code "
"}, and {@code "
"}
   * respectively. Any other non-ASCII characters appearing in the input will be preserved in the
   * output.
   *
   * <p>This escaper does not treat surrogate pairs specially and does not perform Unicode

   * (NCR). However, horizontal tab {@code '\t'}, line feed {@code '\n'} and carriage return {@code
   * '\r'} are escaped to a corresponding NCR {@code "	"}, {@code "
"}, and {@code "
"}
   * respectively. Any other non-ASCII characters appearing in the input will be preserved in the
   * output.
   *
   * <p>This escaper does not treat surrogate pairs specially and does not perform Unicode

    // Test all escapes
    assertEquals(
        "a&quot;b&lt;c&gt;d&amp;e&quot;f&apos;", xmlAttributeEscaper.escape("a\"b<c>d&e\"f'"));
    // Test '\t', '\n' and '\r' are escaped.
    assertEquals("a&#x9;b&#xA;c&#xD;d", xmlAttributeEscaper.escape("a\tb\nc\rd"));
  }

  // Helper to assert common properties of xml escapers.
  static void assertBasicXmlEscaper(

    // Test all escapes
    assertEquals(
        "a&quot;b&lt;c&gt;d&amp;e&quot;f&apos;", xmlAttributeEscaper.escape("a\"b<c>d&e\"f'"));
    // Test '\t', '\n' and '\r' are escaped.
    assertEquals("a&#x9;b&#xA;c&#xD;d", xmlAttributeEscaper.escape("a\tb\nc\rd"));
  }

  // Helper to assert common properties of xml escapers.
  static void assertBasicXmlEscaper(

		}
	}
	return n
}

// skipCSSSpace returns a suffix of c, skipping over a single space.
func skipCSSSpace(c []byte) []byte {
	if len(c) == 0 {
		return c
	}
	// wc ::= #x9 | #xA | #xC | #xD | #x20
	switch c[0] {
	case '\t', '\n', '\f', ' ':
		return c[1:]
	case '\r':
		// This differs from CSS3's wc production because it contains a
		// probable spec error whereby wc contains all the single byte

00000140  d5 95 7a 5b ba b6 ab 87  90 a5 35 19 bf 99 2c 04  |..z[......5...,.|
00000150  93 61 e3 9b 5c 06 48 38  f0 25 8a be 30 cd 43 c0  |.a..\.H8.%..0.C.|
00000160  10 c9 1d 51 3e 93 5f 6c  02 1c 38 fe 78 44 1a ea  |...Q>._l..8.xD..|
00000170  99 a4 ef 7d 03 ce 71 95  d7 1d e1 b3 b8 e2 20 99  |...}..q....... .|
00000180  aa 30 0f c1 75 a7 0d 39  98 12 96 27 c6 39 b8 57  |.0..u..9...'.9.W|

00000070  ff f6 84 af c4 cf c2 ed  90 99 5f 58 cb 3b 74 14  |.........._X.;t.|
00000080  03 03 00 01 01 17 03 03  00 17 e4 b2 43 7d 15 fc  |............C}..|
00000090  ae 58 44 9d 0d 82 a4 1c  21 c4 3f 86 fb 4b 6b d1  |.XD.....!.?..Kk.|
000000a0  96 17 03 03 02 6d 03 84  7a 2c 7e d8 c8 ca 31 07  |.....m..z,~...1.|
000000b0  fc 2c 47 5b e4 c1 e1 5f  1a c9 a0 45 4e 9a 3d 63  |.,G[..._...EN.=c|

00000110  e9 62 ed 3d 80 da 38 22  c6 c3 fd 1c b2 d2 8c 74  |.b.=..8".......t|
00000120  23 39 70 67 b0 34 25 24  eb 72 e2 c1 63 d6 48 09  |#9pg.4%$.r..c.H.|
00000130  ee d7 5e 15 2b 78 64 97  c8 d0 6b 2a 1c b6 d8 12  |..^.+xd...k*....|
00000140  9e 9a b5 dc 24 51 5a 38  a1 4c 9c df 74 3f 63 f0  |....$QZ8.L..t?c.|
00000150  d2 45 49 58 5c 3c 42 f2  56 fd bc 0e c1 d6 8b 7d  |.EIX\<B.V......}|