LayoutTests/ietestcenter/Javascript/TestCases/11.4.1-4.a-10.js

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/*
This test is actually testing the [[Delete]] internal method (8.12.8). Since the
language provides no way to directly exercise [[Delete]], the tests are placed here.
*/

ES5Harness.registerTest( {
id: "11.4.1-4.a-10",

path: "TestCases/chapter11/11.4/11.4.1/11.4.1-4.a-10.js",

description: "delete operator returns true for property (stringify) defined on built-in object (JSON)",

test: function testcase() {
  try {
      var o = JSON.stringify;
      var desc;
      try {
          desc = Object.getOwnPropertyDescriptor(JSON, 'stringify')
      } 
      catch (e) {
      };
      var d = delete JSON.stringify;
      if (d === true && JSON.stringify === undefined) {
        return true;
      }
  } finally {
    if (desc) Object.defineProperty(JSON, 'stringify', desc)
    else JSON.stringify = o  /* this branch screws up the attributes */;
  }
 }
});