Run results for: For loop vs reduce array change and update

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36

Browser: Chrome 71

Operating system: Mac OS X 10.14.1

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
For loop	1398153.0 Ops/sec
Reduce	5894325.0 Ops/sec

Script Preparation code:

var testArray = [{
test: '123',
arr:[{
  id: 1,
  description: 'Random description.',
  testDate: new Date(),
  testBoolean: true,
  testObject: {
    testString: 'test string',
    testNumber: 12345
  },
  testArray: [{
    myName: 'test name',
    myNumber: 123245
  }]
},{
  id: 2,
  description: 'Random descriptionfdsgdfgd.',
  testNumber: 123456789,
  testBoolean: true,
  testObject: {
    testString: 'test string',
    testNumber: 12345
  },
  testArray: [{
    myName: 'test name',
    myNumber: 123245
  }]
}]
},
{
test: '1234',
arr:[{
  id: 1,
  description: 'Random description.',
  testDate: new Date(),
  testBoolean: true,
  testObject: {
    testString: 'test string',
    testNumber: 12345
  },
  testArray: [{
    myName: 'test name',
    myNumber: 123245
  }]
},{
  id: 2,
  description: 'Random descriptionfdsgdfgd.',
  testNumber: 123456789,
  testBoolean: true,
  testObject: {
    testString: 'test string',
    testNumber: 12345
  },
  testArray: [{
    myName: 'test name',
    myNumber: 123245
  }]
}]
}];

function reduceIt(arr){
 return arr.reduce((acc, val)=>{
   if(val.id == 2){
   	val.description = 'changed it!';
     acc.push(val);
     return acc;
   }
   acc.push(val);
   return acc;
 },[]); 
}

function loopIt(arr){
  var newArray = [];
  for(var x = 0; x < testArray.length; x++){
    if(testArray[x].id == 2){
      testArray[x].description = 'changed it!';
      newArray.push(testArray[x]);
    }
    newArray.push(testArray[x]);
  }
  return newArray;
}

Tests:

For loop
var changeLoop = loopIt(testArray);
Reduce
var changeReduce = reduceIt(testArray);

Run results for: For loop vs reduce array change and update

for loop vs reduce in new array creation

For loop

Reduce