Let's dive into the world of JavaScript benchmarks.

What is being tested?

MeasureThat.net is testing two different approaches to merge two objects in JavaScript:

1. Using the spread operator (... syntax)
2. Using Object.assign() with an empty object literal ({})

The benchmark aims to compare the performance of these two methods.

Options compared:

• Spread operator (... syntax)
  • Pros:
    • More concise and readable
    • Less error-prone than using Object.assign()
  • Cons:
    • May be slower due to the overhead of creating a new object
• Object.assign() with an empty object literal ({})
  • Pros:
    • Can be faster since it only creates one object
  • Cons:
    • Less concise and less readable than using the spread operator

Other considerations:

• The benchmark uses Chrome 78 on a Linux desktop as the base environment.
• The ExecutionsPerSecond metric is used to measure performance, which indicates the number of executions per second.

Library usage:

None. This benchmark does not use any external libraries.

Special JS feature or syntax:

The spread operator (...) is a relatively new JavaScript feature introduced in ECMAScript 2018. It allows for more concise and expressive object merging.

Benchmark preparation code:

The provided Script Preparation Code is empty, which means that the benchmark starts with clean slate and no initialization code is executed before running the test cases.

Individual test cases:

There are two test cases:

1. "Using the spread operator"
   • This test case uses the spread operator to merge two objects (firstObject and secondObject) into a new object (finalObject).
2. "Using Object.assign"
   • This test case uses Object.assign() with an empty object literal ({}) to merge two objects (firstObject and secondObject) into a new object (finalObject).

Latest benchmark result:

The latest results show that:

• The spread operator approach is slightly faster than using Object.assign().
• However, the difference in performance is not significant.

Keep in mind that this is just one specific benchmark, and results may vary depending on the JavaScript engine, version, and other factors.