text: // Copyright 2009 the Sputnik authors.  All rights reserved.
  // This code is governed by the BSD license found in the LICENSE file.
  
  /*---
  info: >
      A property name P (in the form of a string value) is an array index
      if and only if ToString(ToUint32(P)) is equal to P and ToUint32(P) is not equal to 2^32 - 1
  es5id: 15.4_A1.1_T5
  description: Checking for null and undefined
  ---*/
  
  //CHECK#1
  x = [];
  x[null] = 0;
  if (x[0] !== undefined) {
    $ERROR('#1: x = []; x[null] = 1; x[0] === undefined. Actual: ' + (x[0]));  
  }
  
  //CHECK#2
  if (x["null"] !== 0) {
    $ERROR('#2: x = []; x[null] = 1; x["null"] === 0. Actual: ' + (x["null"]));  
  }
  
  //CHECK#3
  y = [];
  y[undefined] = 0;
  if (y[0] !== undefined) {
    $ERROR('#3: y = []; y[undefined] = 0; y[0] === undefined. Actual: ' + (y[0]));  
  }
  
  //CHECK#4
  if (y["undefined"] !== 0) {
    $ERROR('#4: y = []; y[undefined] = 1; y["undefined"] === 0. Actual: ' + (y["undefined"]));  
  }
  