Benchmark: JSON.stringify vs structuredClone vs simple deepCopyObject 3

Script Preparation code:

var deepCopyObject = (inObject) => {
  if (inObject instanceof Date) return inObject

  if (inObject instanceof Set) return new Set(inObject)

  if (inObject instanceof Map) return new Map(inObject)

  if (typeof inObject !== 'object' || inObject === null) {
    return inObject // Return the value if inObject is not an object
  }

  // Create an array or object to hold the values
  const outObject = Array.isArray(inObject) ? [] : {}

  Object.keys(inObject).forEach((key) => {
    const value = inObject[key]

    // Recursively (deep) copy for nested objects, including arrays
    outObject[key] = typeof value === 'object' && value !== null ? deepCopyObject(value) : value
  })

  return outObject
}

function deepCopyObjectSimple(inObject) {
  if (typeof inObject !== 'object' || inObject === null) {
    return inObject;
  }

  const outObject = Array.isArray(inObject) ? [] : {};

  for (const key in inObject) {
    const value = inObject[key];
    outObject[key] = (typeof value === 'object' && value !== null) ? deepCopyObjectSimple(value) : value;
  }

  return outObject;
}

function deepCopyObjectIterative(inObject) {
  if (typeof inObject !== 'object' || inObject === null) {
    return inObject;
  }

  const stack = [{ source: inObject, target: Array.isArray(inObject) ? [] : {} }];
  const root = stack[0].target;

  while (stack.length > 0) {
    const { source, target } = stack.pop();

    for (const key in source) {
      const value = source[key];
      if (typeof value === 'object' && value !== null) {
        target[key] = Array.isArray(value) ? [] : {};
        stack.push({ source: value, target: target[key] });
      } else {
        target[key] = value;
      }
    }
  }

  return root;
}

var MyObject = {
  description: 'Creates a deep copy of source, which should be an object or an array.',
  myNumber: 123456789,
  myBoolean: true,
  jayson: {
    stringify: 'JSON.stringify() method converts a JavaScript value to a JSON string....',
    parse: 'JSON.parse() method parses a JSON string...'
  }
};

var myCopy = null;

Tests:

JSON.stringify
myCopy = JSON.parse(JSON.stringify(MyObject));
structuredClone
myCopy = structuredClone(MyObject);
deepCopyObject
myCopy = deepCopyObject(MyObject);
deepCopyObjectSimple
myCopy = deepCopyObjectSimple(MyObject);
deepCopyObjectIterative
myCopy = deepCopyObjectIterative(MyObject);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
JSON.stringify
structuredClone
deepCopyObject
deepCopyObjectSimple
deepCopyObjectIterative

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 2 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36

Browser/OS: Chrome 126 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
JSON.stringify	1446061.0 Ops/sec
structuredClone	817268.3 Ops/sec
deepCopyObject	1303168.0 Ops/sec
deepCopyObjectSimple	3451856.0 Ops/sec
deepCopyObjectIterative	3508499.0 Ops/sec

JSON.stringify vs structuredClone vs simple deepCopyObject 3 (version: 0)

JSON.stringify vs structuredClone vs simple deepCopyObject 3

Comparing performance of: JSON.stringify vs structuredClone vs deepCopyObject vs deepCopyObjectSimple vs deepCopyObjectIterative

Created: 2 months ago by: Guest

Jump to the latest result

JSON.stringify

structuredClone

deepCopyObject

deepCopyObjectSimple

deepCopyObjectIterative

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A