The benchmark you're examining evaluates the performance of two different methods for creating objects in JavaScript that do not inherit from any prototypes. The methods being compared are:

1. Using __proto__: null
2. Using Object.create(null)

Test Cases

1. __proto__: null: This syntax is a way to create an object with no prototype. By using __proto__: null, you create an object literal that does not inherit from Object.prototype, meaning it won't have access to methods such as toString or other prototype methods.

   for(let i=300; i--;) var a = {__proto__: null};
   

2. Object.create(null): This method is a standard JavaScript function that creates a new object with the specified prototype object and properties. When null is passed in, it creates an object with no prototype. This approach is widely recognized for its clarity and intent.

   for(let i=300; i--;) var a = Object.create(null);
   

Performance Results

From the benchmark results, we can observe the following executions per second for each method:

• Object.create(null): Approximately 93,990 executions per second
• __proto__: null: Approximately 60,303 executions per second

This indicates that Object.create(null) is significantly faster in this scenario.

Pros and Cons of Each Approach

1. __proto__: null

• Pros:
  • Concise and straightforward syntax when creating an object.
• Cons:
  • Slightly less performance efficient as shown in the benchmark.
  • Less conventional and might confuse developers who are less familiar with this syntax.
  • Potentially increases the risk of inadvertently misunderstanding inheritance and prototypes in JavaScript.

2. Object.create(null)

• Pros:
  • Clearly conveys the intent of creating an object without a prototype, enhancing readability.
  • Offers better performance based on the benchmark results.
  • Ensures consistency and is a more recognized practice among developers.
• Cons:
  • Slightly more verbose than the direct object literal method.

Other Considerations

When choosing between these two approaches, readability and consistency in code should be factored into a developer's decision. While both methods achieve the goal of creating prototype-less objects, using Object.create(null) is preferable for long-term maintainability—especially in teams or projects where code clarity is critical.

Other Alternatives

• Another common way of creating plain objects is using the object literal notation ({}), but these objects have Object.prototype as a prototype by default, making them unsuitable if a non-inheriting object is desired.
• Additionally, some developers may consider using ES6 class syntax to define prototypes, but this adds unnecessary complexity for the specific task of creating plain objects.

In conclusion, while both methods serve to create objects with no prototype, Object.create(null) is generally the preferred choice due to its performance and readability advantages.