text: // Copyright (C) 2015 André Bargull. All rights reserved.
  // This code is governed by the BSD license found in the LICENSE file.
  
  /*---
  description: B.1.4 is not applied for Unicode RegExp - Invalid control escape sequences
  info: |
      The compatibility extensions defined in B.1.4 Regular Expressions Patterns
      are not applied for Unicode RegExp.
      Tested extension: "IdentityEscape[U] :: [~U] SourceCharacter but not c"
  es6id: 21.1.2
  ---*/
  
  function isAlpha(c) {
    return ("A" <= c && c <= "Z") || ("a" <= c && c <= "z");
  }
  
  
  // "c ControlLetter" sequence in AtomEscape.
  //
  // AtomEscape[U] :: CharacterEscape[?U]
  // CharacterEscape[U] :: c ControlLetter
  assert.throws(SyntaxError, function() { RegExp("\\c", "u"); });
  for (var cu = 0x00; cu <= 0x7f; ++cu) {
    var s = String.fromCharCode(cu);
    if (!isAlpha(s)) {
      assert.throws(SyntaxError, function() {
        RegExp("\\c" + s, "u");
      }, "ControlLetter escape in AtomEscape: '" + s + "'");
    }
  }
  
  
  // "c ControlLetter" sequence in ClassEscape.
  //
  // ClassEscape[U] :: CharacterEscape[?U]
  // CharacterEscape[U] :: c ControlLetter
  assert.throws(SyntaxError, function() { RegExp("[\\c]", "u"); });
  for (var cu = 0x00; cu <= 0x7f; ++cu) {
    var s = String.fromCharCode(cu);
    if (!isAlpha(s)) {
      assert.throws(SyntaxError, function() {
        RegExp("[\\c" + s + "]", "u");
      }, "ControlLetter escape in ClassEscape: '" + s + "'");
    }
  }
  