Benchmark: lodash merge vs lodash assign vs object.assign vs spread 2

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js'></script>

Tests:

lodash merge
var a = { a: 'oh', b: 'my', d: { x: 1 } }; var b = { c: 'goddess', d: { x: 2, y: 99 } }; var c = _.merge(a, b);
lodash assign
var a = { a: 'oh', b: 'my', d: { x: 1 } }; var b = { c: 'goddess', d: { x: 2, y: 99 } }; var c = _.assign(a, b);
spread
var a = { a: 'oh', b: 'my', d: { x: 1 } }; var b = { c: 'goddess', d: { x: 2, y: 99 } }; var c = { ...a, ...b };
assign
var a = { a: 'oh', b: 'my', d: { x: 1 } }; var b = { c: 'goddess', d: { x: 2, y: 99 } }; var c = Object.assign({}, a, b);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash merge
lodash assign
spread
assign

Fastest: N/A

Slowest: N/A

Latest run results:

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

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Let's break down the benchmark and explain what's being tested.

**What is being tested?**

The benchmark is comparing the performance of four different ways to merge two objects in JavaScript:

1. `_.merge` from Lodash
2. `_.assign` from Lodash
3. Using the spread operator (`{ ...a, ...b }`)
4. Using `Object.assign()` with an empty object as the first argument (`Object.assign({}, a, b)`)

**Options being compared:**

* **Lodash merge (`_.merge`) and Lodash assign (`_.assign`)**: These two functions are part of the Lodash library, which provides a set of useful JavaScript utilities. Both functions take two objects as input and return a new object that is the result of merging or assigning properties from both objects.
	+ Pros:
		- Easy to use and understand
		- Provide additional features beyond simple object assignment (e.g., support for arrays, null/undefined values)
	+ Cons:
		- Add dependencies (the Lodash library)
		- May have a larger overhead compared to native JavaScript methods
* **Spread operator (`{ ...a, ...b }`)**: This syntax is a shorthand way to create a new object with properties from both `a` and `b`.
	+ Pros:
		- Very concise and easy to read
		- No dependencies or additional overhead
	+ Cons:
		- Only works for objects with the same structure (i.e., same keys)
		- Can be less readable if the objects have different structures
* **`Object.assign()` with an empty object as the first argument (`Object.assign({}, a, b)`)**: This method is used to merge two or more objects into one.
	+ Pros:
		- Works for any type of objects (not just plain JavaScript objects)
		- Can be used with other types of values (e.g., arrays, null/undefined) if needed
	+ Cons:
		- May have a larger overhead compared to native JavaScript methods
		- Requires creating an empty object first

**Other considerations:**

* The benchmark uses a simple example where two objects are merged into one. In real-world scenarios, you may need to handle more complex cases (e.g., merging arrays, handling null/undefined values).
* The use of the Lodash library adds dependencies and overhead, which can impact performance.
* The spread operator is a concise way to merge objects but may not be suitable for all cases.

**Latest benchmark result:**

The latest results show that:

* `Object.assign()` with an empty object as the first argument performs the best ( lowest executions per second)
* `_.merge` from Lodash comes in second
* `_.assign` from Lodash is third
* Using the spread operator performs the worst

This suggests that for simple object merging, using native JavaScript methods (`Object.assign()`) or Lodash functions (`_.merge` and `_._assign`) may be more efficient than relying on the spread operator.

Related benchmarks:

lodash merge vs lodash assign vs object.assign vs spread 2 (version: 0)

Comparing performance of: lodash merge vs lodash assign vs spread vs assign

Created: 7 years ago by: Guest

Jump to the latest result

lodash merge

lodash assign

spread

assign

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):