Benchmark: merge fn vs deepmerge

HTML Preparation code:

<script>const merge = (target, source) => {
        // Iterate through `source` properties and if an `Object` set property to merge of `target` and `source` properties
        for (const key of Object.keys(source)) {
          if (source[key] instanceof Object)
            Object.assign(source[key], merge(target[key], source[key]))
        }

        // Join `target` and modified `source`
        Object.assign(target || {}, source)
        return target
      }</script>
<script src='https://unpkg.com/deepmerge@3.2.0/dist/umd.js'></script>

Tests:

merge
var a = { a: 'oh', b: 'my', c: { a: 'a', b: { c: 'c' } } }; var b = { c: { b: { d: 'a' }, c: { d: 'd' } } }; var c = merge(a, b);
object.assign
var a = { a: 'oh', b: 'my', c: { a: 'a', b: { c: 'c' } } }; var b = { c: { b: { d: 'a' }, c: { d: 'd' } } }; var c = deepmerge({}, a, b);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
merge
object.assign

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.212 Safari/537.36

Browser/OS: Chrome 90 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
merge	1460512.1 Ops/sec
object.assign	908203.6 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared, and their pros and cons.

**What's being tested?**

Two JavaScript functions are being compared:

1. `merge` function (defined in the Script Preparation Code)
2. `deepmerge` library (imported from a CDN)

The tests focus on creating deep merges of objects using these two approaches. Specifically, they're comparing the performance of merging two nested object graphs.

**What options are compared?**

Two options are being compared:

1. **Custom merge function**: The `merge` function defined in the Script Preparation Code. This function iterates through properties, checking if they're objects and recursively merging them.
2. **Deepmerge library**: A third-party library (`deepmerge`) that provides a more efficient and optimized way to perform deep merges.

**Pros and Cons:**

1. **Custom merge function**:
	* Pros:
		+ No external dependencies (only JavaScript)
		+ Simple and straightforward implementation
	* Cons:
		+ May be slower due to the recursive iteration
		+ Can be less efficient for large object graphs
2. **Deepmerge library**:
	* Pros:
		+ Optimized for performance, using advanced algorithms and caching
		+ Handles complex merge scenarios with ease
	* Cons:
		+ External dependency (requires a CDN import)
		+ May add overhead due to the library's abstraction layer

**Library: Deepmerge**

The `deepmerge` library is designed to provide a fast, efficient, and flexible way to perform deep merges of objects. It uses advanced algorithms and caching techniques to optimize performance.

In this benchmark, `deepmerge` is used to merge two nested object graphs using its `deepMerge()` function. The test case provides the input objects (`a` and `b`) and expects the output to be a merged object (`c`).

**Special JS feature or syntax**

There are no special JavaScript features or syntaxes being tested in this benchmark.

**Other alternatives**

If you're interested in exploring alternative merge functions, here are a few options:

1. **lodash.merge()**: A popular utility library that provides a `merge()` function for deep merging objects.
2. **immer.merge()`: An immutable merge function from the Immer library, which ensures that merged objects are updated in place.
3. **Object.assign()**: A built-in JavaScript method for assigning properties of one object to another.

Keep in mind that these alternatives may have different performance characteristics and use cases compared to the `merge` function defined in the Script Preparation Code or the `deepmerge` library.

Related benchmarks:

merge fn vs deepmerge (version: 0)

Comparing performance of: merge vs object.assign

Created: 4 years ago by: Guest

Jump to the latest result

merge

object.assign

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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