Benchmark: Object.assign vs direct assignment (Improved cases)

Script Preparation code:

var data = {};

Tests:

Direct Assignment
for(var i = 0; i < 10000; i++) { data[`prop_${i}`] = null; }
Object.assign
for(var i = 0; i < 10000; i++) { Object.assign(data, { [`prop_${i}`]: null }); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Direct Assignment
Object.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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I'll break down the provided benchmark and explain what's being tested, compared options, pros and cons, library usage, special JavaScript features or syntax, and alternative approaches.

**Benchmark Overview**

The test compares two approaches for assigning properties to an object:

1. **Direct Assignment**: Assigning a property directly using the object literal syntax (e.g., `data['prop_0'] = null;`).
2. **Object.assign**: Using the built-in `Object.assign()` method to assign properties to an object (e.g., `Object.assign(data, { 'prop_0': null });`).

**Options Compared**

The two options are compared in terms of:

* Execution time: The test measures how long each approach takes to execute.
* Performance difference: The test aims to determine which approach is faster and more efficient.

**Pros and Cons**

1. **Direct Assignment**:
	* Pros:
		+ Typically faster and more efficient, as it avoids the overhead of a function call.
		+ May be preferred for simple cases where performance matters.
	* Cons:
		+ Can lead to unexpected behavior if not used carefully (e.g., when dealing with property names that contain special characters or have spaces).
2. **Object.assign**:
	* Pros:
		+ Provides a clear and explicit way of assigning properties to an object.
		+ Can be useful when working with complex data structures or when the property names are not known until runtime.
	* Cons:
		+ Typically slower than direct assignment due to the function call overhead.
		+ May incur additional memory allocations if the assigned values are objects.

**Library Usage**

There is no explicit library usage in this benchmark. However, it's worth noting that `Object.assign()` has been a part of the JavaScript language since ECMAScript 2015 (ES6).

**Special JavaScript Features or Syntax**

None mentioned in the provided benchmark definition and test cases.

**Alternative Approaches**

Other approaches to assigning properties to an object include:

* Using the bracket notation (`data['prop_0'] = null;`): This approach is similar to direct assignment but uses a string expression instead of a property name.
* Using the spread operator (`{ ...data, prop_0: null }[0] = data;`): This approach is more concise than using `Object.assign()` and can be faster in some cases.

Keep in mind that these alternative approaches may not always offer significant performance improvements over direct assignment or `Object.assign()`. The best choice ultimately depends on the specific use case, personal preference, and coding style.

Related benchmarks:

Object.assign vs direct assignment (Improved cases) (version: 0)

Comparing performance of: Direct Assignment vs Object.assign

Created: 4 years ago by: Guest

Jump to the latest result

Direct Assignment

Object.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):