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

Benchmark Definition

The test compares three JavaScript methods for merging objects:

1. Object.assign()
2. Spread operator (...)
3. jQuery.extend()

Options Compared

Each method has its own strengths and weaknesses, which we'll discuss next:

Object.assign()

• Pros:
  • Widely supported across browsers and platforms.
  • Simple to use.
  • Fast (average execution time).
• Cons:
  • Can be slower than the spread operator in some cases.
  • Requires compatibility with older browsers.

Spread Operator (...)

• Pros:
  • Fastest average execution time among the three methods.
  • More concise and expressive syntax.
  • Widely supported across modern browsers.
• Cons:
  • Limited support for older browsers (IE 11 and below).
  • May be slower than Object.assign() in some cases.

jQuery.extend()

• Pros:
  • Well-known and widely used library.
  • Supports a wider range of browsers, including older versions.
  • Can provide additional functionality beyond basic object merging.
• Cons:
  • Adds extra weight to the code due to the inclusion of the entire jQuery library.
  • May be slower than other methods.

Library

The test uses jQuery 3.1.1 as the reference implementation for jQuery.extend(). The purpose of this function is to merge two or more objects into a single object, with the source objects' properties being overwritten by their destination values.

Special JavaScript Feature/Syntax

None are explicitly mentioned in this benchmark.

Other Alternatives

In addition to these three methods, other alternatives for merging objects include:

• Using the Object.create() method with the assign property.
• Utilizing a library like Lodash or Ramda, which provide more advanced features beyond basic object merging.
• Implementing your own custom merge function.

These alternatives may offer additional performance benefits or simplify code in specific use cases, but they are not part of the standard JavaScript API and may require additional setup.