The Tor Browser / file revision

 /* test Set.prototype.forEach */

 load(libdir + 'asserts.js');

 load(libdir + 'iteration.js');

 // testing success conditions of Set.prototype.forEach

 var testSet = new Set();

 function callback(value, key, set) {

     assertEq(value, key);

     testSet.add(value);

     assertEq(set.has(key), true);

 }

 var initialSet = new Set(['a', 1, undefined]);

 initialSet.forEach(callback);

 // test that both the Sets are equal and are in same order

 var iterator = initialSet[std_iterator]();

 var count = 0;

 for (var v of testSet) {

     assertEq(initialSet.has(v), true);

     assertIteratorNext(iterator, v);

     count++;

 }

 //check both the Sets we have are equal in size

 assertEq(initialSet.size, testSet.size);

 assertEq(initialSet.size, count);

 var x = { abc: 'test'};

 function callback2(value, key, set) {

     assertEq(x, this);

 }

 initialSet = new Set(['a']);

 initialSet.forEach(callback2, x);

 // testing failure conditions of Set.prototype.forEach

 var m = new Map([['a', 1], ['b', 2.3], ['c', undefined]]);

 assertThrowsInstanceOf(function() {

     Set.prototype.forEach.call(m, callback);

 }, TypeError, "Set.prototype.forEach should raise TypeError if not a used on a Set");

 var fn = 2;

 assertThrowsInstanceOf(function() {

     initialSet.forEach(fn);

 }, TypeError, "Set.prototype.forEach should raise TypeError if callback is not a function");