Run results for: Lodash cloneDeep vs native cloneDeep vs structuredClone

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:138.0) Gecko/20100101 Firefox/138.0

Browser: Firefox 138

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

Native map(shallow clone)

39.7M/s

Object.assign shallow clone

36.9M/s

Native map deep slice(turns objects into arrays)

21.0M/s

Native map deep slice at 0(turns objects into arrays)

19.3M/s

Recursive deep clone

1.7M/s

Map deep clone

885K/s

Native JSON parse

665K/s

structuredClone

506K/s

Lodash cloneDeep

367K/s

View exact numbers

Test name	Executions per second
✓ Native map(shallow clone)	39,734,848 Ops/sec
Object.assign shallow clone	36,884,556 Ops/sec
Native map deep slice(turns objects into arrays)	21,010,224 Ops/sec
Native map deep slice at 0(turns objects into arrays)	19,335,886 Ops/sec
Recursive deep clone	1,656,294 Ops/sec
Map deep clone	885,428 Ops/sec
Native JSON parse	665,375 Ops/sec
structuredClone	505,623 Ops/sec
Lodash cloneDeep	367,176 Ops/sec

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var testArray = [{
  description: 'Random description.',
  testNumber: 123456789,
  testBoolean: true,
  testObject: {
    testString: 'test string',
    testNumber: 12345
  },
  testArray: [{
    myName: 'test name',
    myNumber: 123245
  }]
},{
  description: 'Random description.',
  testNumber: 123456789,
  testBoolean: true,
  testObject: {
    testString: 'test string',
    testNumber: 12345
  },
  testArray: [{
    myName: 'test name',
    myNumber: 123245
  }]
}];

var testCopy = null;

var deepClone = function(obj) {
   var out;
    if (Array.isArray(obj)) {
        out = [];
        for (var index = 0; index < obj.length; ++index) {
            let subArray = obj[index];
            out.push((subArray === null) ? subArray : (subArray instanceof Date) ? new Date(subArray.valueOf()) : (typeof subArray === 'object') ? deepClone(subArray) : subArray);
        }
    } else {
        out = {};
        for (var key in obj) {
            var subObject = obj[key];
            out[key] = subObject === null ? subObject : subObject instanceof Date ? new Date(subObject.valueOf()) : (typeof subObject === 'object') ? deepClone(subObject) : subObject;
            
           
        }
    }
    return out;
};

Tests:

Lodash cloneDeep
testCopy = _.cloneDeep(testArray);
Native map deep slice(turns objects into arrays)
testCopy = testArray.map(arr => testArray.slice());
Native JSON parse
testCopy = JSON.parse(JSON.stringify(testArray));
Native map deep slice at 0(turns objects into arrays)
testCopy = testArray.map(arr => testArray.slice(0));
Native map(shallow clone)
testCopy = testArray.map(arr => arr);
Recursive deep clone
testCopy = deepClone(testArray);
Map deep clone
testCopy = testArray.map(arr => deepClone(arr));
Object.assign shallow clone
testCopy = Object.assign([...testArray]);
structuredClone
testCopy = structuredClone(testArray);