const firstObject = { sampleData: 'Hello world' }
const secondObject = { moreData: 'foo bar' }
const finalObject = {
firstObject,
secondObject
};
const firstObject = { sampleData: 'Hello world' }
const secondObject = { moreData: 'foo bar' }
const finalObject = {};
Object.assign(finalObject, firstObject, secondObject);
const firstObject = { sampleData: 'Hello world' }
const secondObject = { moreData: 'foo bar' }
const finalObject = {};
Object.assign(finalObject, { firstObject, secondObject });
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Using the spread operator | |
Using Object.assign | |
ajostg[pf |
Test name | Executions per second |
---|---|
Using the spread operator | 10051234.0 Ops/sec |
Using Object.assign | 1965391.2 Ops/sec |
ajostg[pf | 1644342.9 Ops/sec |
Overview
The provided benchmark definition measures the performance of two methods: using the JavaScript spread operator (...
) and Object.assign()
to merge two objects into a single object.
Test Cases
There are three test cases:
...
) to merge two objects, firstObject
and secondObject
, into a single object, finalObject
. The syntax is: { ...firstObject, ...secondObject }
.Object.assign()
method to merge two objects, firstObject
and secondObject
, into a single object, finalObject
. The syntax is: Object.assign(finalObject, firstObject, secondObject)
.Library and Purpose
Object.assign()
is a native method of the Object
class since ECMAScript 2009 (ES5).Special JS Features or Syntax
The test cases use the spread operator, which is a relatively recent addition to the JavaScript language. It's a concise way to merge objects, but it may not be supported in older browsers or environments.
Pros and Cons of Different Approaches
Alternatives
Other alternatives for merging objects in JavaScript include:
lodash
library's merge()
function or other utility functions.Keep in mind that the performance difference between these alternatives may be negligible for most use cases. The choice ultimately depends on personal preference, coding style, and specific requirements.
Additional Considerations
When creating benchmarks like this one, consider the following: