Tests:
  • Using the spread operator

    x
     
    const firstObject = {}
    const secondObject = {}
    for(let i = 1; i < 1000; i++) firstObject[i] = Math.random();
    for(let i = 1; i < 1000; i++) secondObject[i] = firstObject[i];
    let rnd = Math.floor(Math.random() * 1000);
    secondObject[rnd] = Math.random();
    const finalObject = {
        ...firstObject,
        ...secondObject
    };
    console.log("first", firstObject)
    console.log("second", secondObject)
    console.log("final", finalObject)
  • Using Object.assign

     
    const firstObject = {}
    const secondObject = {}
    for(let i = 1; i < 1000; i++) firstObject[i] = Math.random();
    for(let i = 1; i < 1000; i++) secondObject[i] = firstObject[i];
    let rnd = Math.floor(Math.random() * 1000);
    secondObject[rnd] = Math.random();
    const finalObject = Object.assign(firstObject, secondObject);
    console.log("first", firstObject)
    console.log("second", secondObject)
    console.log("final", finalObject)
  • Using Object.assign (known change)

     
    const firstObject = {}
    const secondObject = {}
    for(let i = 1; i < 1000; i++) firstObject[i] = Math.random();
    for(let i = 1; i < 1000; i++) secondObject[i] = firstObject[i];
    let rnd = Math.floor(Math.random() * 1000);
    secondObject[rnd] = Math.random();
    let diff = {}
    diff[rnd] = secondObject[rnd];
    const finalObject = Object.assign(firstObject, diff);
    console.log("first", firstObject)
    console.log("second", secondObject)
    console.log("final", finalObject)
  • Using the spread operator (known change)

     
    const firstObject = {}
    const secondObject = {}
    for(let i = 1; i < 1000; i++) firstObject[i] = Math.random();
    for(let i = 1; i < 1000; i++) secondObject[i] = firstObject[i];
    let rnd = Math.floor(Math.random() * 1000);
    secondObject[rnd] = Math.random();
    let diff = {}
    diff[rnd] = secondObject[rnd];
    const finalObject = {
        ...firstObject,
        ...diff
    };
    console.log("first", firstObject)
    console.log("second", secondObject)
    console.log("final", finalObject)
  • Using Object.assign (filtered)

     
    const firstObject = {}
    const secondObject = {}
    for(let i = 1; i < 1000; i++) firstObject[i] = Math.random();
    for(let i = 1; i < 1000; i++) secondObject[i] = firstObject[i];
    let rnd = Math.floor(Math.random() * 1000);
    secondObject[rnd] = Math.random();
    let diff = Object.entries(secondObject).filter((value, key) => key == rnd)
    const finalObject = Object.assign(firstObject, diff);
    console.log("first", firstObject)
    console.log("second", secondObject)
    console.log("final", finalObject)
  • Using the spread operator (filter)

     
    const firstObject = {}
    const secondObject = {}
    for(let i = 1; i < 1000; i++) firstObject[i] = Math.random();
    for(let i = 1; i < 1000; i++) secondObject[i] = firstObject[i];
    let rnd = Math.floor(Math.random() * 1000);
    secondObject[rnd] = Math.random();
    let diff = Object.entries(secondObject).filter((value, key) => key == rnd)
    const finalObject = {
        ...firstObject,
        ...diff
    };
    console.log("first", firstObject)
    console.log("second", secondObject)
    console.log("final", finalObject)
Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Experimental features:

  • Test case name Result
    Using the spread operator
    Using Object.assign
    Using Object.assign (known change)
    Using the spread operator (known change)
    Using Object.assign (filtered)
    Using the spread operator (filter)

    Fastest: N/A

    Slowest: N/A

Latest run results:
Run details: (Test run date: 10 months ago)
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36
Chrome 126 on Linux
View result in a separate tab
Test name Executions per second
Using the spread operator 2264.8 Ops/sec
Using Object.assign 2412.3 Ops/sec
Using Object.assign (known change) 6478.3 Ops/sec
Using the spread operator (known change) 6579.4 Ops/sec
Using Object.assign (filtered) 5364.5 Ops/sec
Using the spread operator (filter) 5213.0 Ops/sec