Let's dive into the world of JavaScript microbenchmarks!

Benchmark Overview

The benchmark, hosted on MeasureThat.net, measures the performance of three approaches for assigning properties to an object: Lodash's _assign, the native Object.assign() method, and the spread operator (...).

Test Cases

The benchmark consists of three test cases:

1. Lodash Assing: This test case uses Lodash's _assign function to assign properties to an empty object.

_.assign({}, person);

2. Native Assing: This test case uses the native Object.assign() method to assign properties to an empty object.

Object.assign({}, person);

3. spread: This test case uses the spread operator (...) to assign properties to an empty object.

a = {...person};

Library: Lodash

Lodash is a popular JavaScript utility library that provides a wide range of functional programming helpers. In this benchmark, Lodash's _assign function is used to concatenate two or more objects into one.

Spread Operator (...)

The spread operator is a syntax sugar introduced in ECMAScript 2015 (ES6) for creating new arrays from iterable sources. When used with objects, the spread operator creates a new object by spreading the properties of an existing object into a new object.

Native Object.assign() Method

The native Object.assign() method was introduced in ECMAScript 2015 (ES6) and is used to assign own enumerable properties of source objects to target objects. This method is implemented in most modern JavaScript engines.

Options Compared

In this benchmark, the following options are compared:

• Lodash Assing: Uses Lodash's _assign function.
  • Pros: Convenient and flexible way to concatenate objects. Wide range of utility functions available in Lodash.
  • Cons: Adds an external dependency (Lodash) and may introduce overhead due to its complexity.
• Native Assing: Uses the native Object.assign() method.
  • Pros: Efficient and lightweight, as it's implemented in most JavaScript engines.
  • Cons: May have performance variations depending on the engine implementation.
• spread: Uses the spread operator (...).
  • Pros: Simple and concise syntax. No external dependencies required.
  • Cons: Limited functionality compared to Lodash and native Object.assign().

Other Considerations

When choosing an approach, consider the following factors:

• Performance: If speed is critical, the native Object.assign() method or spread operator may be a better choice.
• Convenience: If you need to perform multiple assignments or concatenations, Lodash's _assign function might be more convenient.
• Dependency management: Be aware that using an external library like Lodash may introduce dependencies that need to be managed.

Alternatives

Other alternatives for assigning properties to objects include:

• Array.prototype.push(): While not ideal for object assignments, push() can be used to assign properties to an array. However, this approach is less efficient and more prone to errors.
• Object.assign() with a spread operator: This approach combines the benefits of native Object.assign() and the spread operator: (a = {...b}).assign(c);
• Library alternatives: Other utility libraries like Underscore.js or Ramda can provide similar functionality to Lodash.