var testCase = function (actual, expected, message) { if (actual !== expected) { throw message + ". Expected '" + expected + "', but was '" + actual + "'"; } }; var obj = { name:'obj', method: function () { return (value) => this.name + "-name-" + value; }}; for (var i=0; i<10000; i++) { testCase(obj.method()('test' + i.toString()), 'obj-name-test' + i.toString(), "Error: this is not lexically binded inside of the arrow function #1"); } for (var i=0; i<10000; i++) { var result1 = obj.method()('test' + i.toString()); testCase(result1, 'obj-name-test' + i.toString(), "Error: this is not lexically binded inside of the arrow function #1"); } obj.name='newObj'; for (var i=0; i<10000; i++) { testCase(obj.method()('test' + i.toString()), 'newObj-name-test' + i.toString(), "Error: this is not lexically binded inside of the arrow function #5"); } for (var i=0; i<10000; i++) { var result2 = obj.method()('test' + i.toString()); testCase(result2, 'newObj-name-test' + i.toString(), "Error: this is not lexically binded inside of the arrow function #5"); }