SOURCE CODE: Uize.Test.Performance.TestingForUndefined (view docs)

/*______________
|       ______  |   U I Z E    J A V A S C R I P T    F R A M E W O R K
|     /      /  |   ---------------------------------------------------
|    /    O /   |    MODULE : Uize.Test.Performance.TestingForUndefined Class
|   /    / /    |
|  /    / /  /| |    ONLINE : http://www.uize.com
| /____/ /__/_| | COPYRIGHT : (c)2008-2016 UIZE
|          /___ |   LICENSE : Available under MIT License or GNU General Public License
|_______________|             http://www.uize.com/license.html
*/

/* Module Meta Data
  type: Test
  importance: 1
  codeCompleteness: 100
  docCompleteness: 100
*/

/*?
  Introduction
    The =Uize.Test.Performance.TestingForUndefined= module defines a performance test that compares different approaches to testing for an undefined value.

    *DEVELOPERS:* `Chris van Rensburg`
*/

Uize.module ({
  name:'Uize.Test.Performance.TestingForUndefined',
  builder:function () {
    'use strict';

    var
      _totalIterations = 500000,
      _testVariableWithUndefinedValue,
      _testVariableWithDefinedValue = 'this is a string value',
      _undefinedStr = 'undefined',
      _undefined
    ;

    return Uize.Test.resolve ({
      title:'Test the performance of different approaches to testing for an undefined value',
      test:[
        {
          title:'typeof myVariable == undefinedStr',
          test:[
            {
              title:'When the variable being tested is undefined',
              test:function () {
                for (var _iterationNo = _totalIterations; --_iterationNo >= 0;) {
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                  typeof _testVariableWithUndefinedValue == _undefinedStr;
                }
                return true;
              }
            },
            {
              title:'When the variable being tested is not undefined',
              test:function () {
                for (var _iterationNo = _totalIterations; --_iterationNo >= 0;) {
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                  typeof _testVariableWithDefinedValue == _undefinedStr;
                }
                return true;
              }
            }
          ]
        },
        {
          title:'typeof myVariable == \'undefined\'',
          test:[
            {
              title:'When the variable being tested is undefined',
              test:function () {
                for (var _iterationNo = _totalIterations; --_iterationNo >= 0;) {
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                  typeof _testVariableWithUndefinedValue == 'undefined';
                }
                return true;
              }
            },
            {
              title:'When the variable being tested is not undefined',
              test:function () {
                for (var _iterationNo = _totalIterations; --_iterationNo >= 0;) {
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                  typeof _testVariableWithDefinedValue == 'undefined';
                }
                return true;
              }
            }
          ]
        },
        {
          title:'myVariable === variableDeliberatelyNotDefined',
          test:[
            {
              title:'When the variable being tested is undefined',
              test:function () {
                for (var _iterationNo = _totalIterations; --_iterationNo >= 0;) {
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                  _testVariableWithUndefinedValue === _undefined;
                }
                return true;
              }
            },
            {
              title:'When the variable being tested is not undefined',
              test:function () {
                for (var _iterationNo = _totalIterations; --_iterationNo >= 0;) {
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                  _testVariableWithDefinedValue === _undefined;
                }
                return true;
              }
            }
          ]
        },
        {
          title:'myVariable === undefined',
          test:[
            {
              title:'When the variable being tested is undefined',
              test:function () {
                for (var _iterationNo = _totalIterations; --_iterationNo >= 0;) {
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                  _testVariableWithUndefinedValue === undefined;
                }
                return true;
              }
            },
            {
              title:'When the variable being tested is not undefined',
              test:function () {
                for (var _iterationNo = _totalIterations; --_iterationNo >= 0;) {
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                  _testVariableWithDefinedValue === undefined;
                }
                return true;
              }
            }
          ]
        }
      ]
    });
  }
});