The provided JSON and benchmark preparation code represent a JavaScript performance test comparing two conditional function calls based on the value of a boolean variable (bool). The benchmark specifically tests how the JavaScript engine handles two different approaches to conditionals and evaluates their execution speed.

Overview of the Benchmark

Benchmark Name: in function call: if true vs if not return

Benchmark Cases

There are two test cases:

1. Test Case 1: "if true then"

   • Benchmark Definition:

     (() => {
       if (bool) {
         i++;
         j = i + 1;
       }
     })();
     

   • In this scenario, the code block inside the if statement is executed because bool is true. This means that both i is incremented, and j is assigned a new value, i + 1.

2. Test Case 2: "if not return"

   • Benchmark Definition:

     (() => {
       if (!bool) return;
       i++;
       j = i + 1;
     })();
     

   • Here, the condition checks if bool is not true. If it is false, the function returns early (exits without executing further) without modifying i or j. If it is true (which it is in this benchmark), the remaining lines execute.

Comparison of Options

• Execution Path:
  • The first test case executes both operations (i++ and j = i + 1), leading to changes in variable states.
  • The second test case has a short-circuit exit via the return statement, effectively skipping the operations when bool is false. This can sometimes be more performant in scenarios where the condition is frequently false.

Performance Results

From the benchmark results:

• "if not return" achieved: 4,465,844.5 executions per second.
• "if true then" achieved: 4,442,367.0 executions per second.

While both test cases performed well, the first test case slightly lagged behind the second in terms of execution speed.

Pros and Cons

• Test Case: "if true then"

  • Pros:
    • Straightforward logic flow for true conditions.
    • Returns a value or modifies variables as intended.
  • Cons:
    • If the conditional is used in scenarios where bool could frequently be false, it might result in unnecessary evaluations and state changes.

• Test Case: "if not return"

  • Pros:
    • Can improve performance when the exit condition is prevalent, as it avoids executing unnecessary code.
    • Clean exit minimizes operations and can be simplified for readability.
  • Cons:
    • If nested logic or additional operations follow this code, early returns can complicate code readability and flow.

Other Considerations

• Execution Context: These benchmarks are run in a JavaScript environment (like a browser), and results could vary based on the JavaScript engine, browser version, and even daily updates.
• Alternatives:
  • A more complex scenario could involve not using return values and relying on flag variables instead.
  • Another alternative may include using ternary operators for inline conditional logic, which can further affect performance depending on complexity and length.

Conclusion

This benchmark explores the implications of straightforward conditional logic and its implications on execution speed. By evaluating the conditional execution paths, developers can better understand how to optimize code for performance based on conditional evaluations in JavaScript.