Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

What is tested?

The provided JSON represents a benchmark test that compares three different ways to check if a property exists in an object:

1. Object.prototype.hasOwnProperty.call(obj, 'b')
2. obj.hasOwnProperty('b')
3. Object.hasOwn(obj, 'b')

These three approaches are compared to determine which one is the fastest.

Options comparison

The three options being compared are:

• 1. Object.prototype.hasOwnProperty.call(obj, 'b'): This method uses the hasOwnProperty() method of the object's prototype chain and returns a boolean value indicating whether the property exists in the object or not.
• 2. obj.hasOwnProperty('b'): This method uses the hasOwnProperty() method of the object itself (not its prototype chain) to check if the property exists.
• 3. Object.hasOwn(obj, 'b'): This method is a static method on the Object class that checks if an object has a given property.

Pros and cons

Here's a brief overview of each option:

1. Object.prototype.hasOwnProperty.call(obj, 'b')
   • Pros: It uses the hasOwnProperty() method of the object's prototype chain, which is a standardized way to check for properties in JavaScript.
   • Cons: It may not be as efficient as using the object's own hasOwnProperty() method (option 2), since it has to traverse the prototype chain.
2. obj.hasOwnProperty('b')
   • Pros: It uses the object's own hasOwnProperty() method, which can be faster than option 1 since it doesn't have to traverse the prototype chain.
   • Cons: It may not be as standardized or widely supported, since it relies on the object having a hasOwnProperty() method in its own prototype chain.
3. Object.hasOwn(obj, 'b')
   • Pros: It is a standardized way to check for properties in JavaScript and doesn't rely on the object's own methods.
   • Cons: It may be slower than option 2 since it has to traverse the object's prototype chain.

Library and syntax

In this benchmark, no libraries are used. The syntax is standard JavaScript, with no special features or syntax.

Other considerations

When writing microbenchmarks like these, it's essential to consider factors such as:

• Standardization: How widely supported is the approach being tested?
• Efficiency: How fast is the approach compared to others?
• Consistency: Are the test cases consistent in their requirements and behavior?

Alternatives

If you were to write a similar benchmark, you might also consider testing other approaches, such as:

• Using the in operator (e.g., obj['b'] in obj)
• Using a library like Lodash or Ramda for property checking
• Testing different versions of JavaScript (e.g., ES5, ES6, etc.)

However, it's worth noting that MeasureThat.net is specifically designed to test microbenchmarks related to property existence and iteration, so the focus on hasOwnProperty() and its variants is likely intentional.