Unveiling Go’s Hidden Gems: Features You Might Have Missed

Kirubakaran

2 min read

·

Sep 12, 2024

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Fuzzing is one of the powerful automated testing techniques which aims to find out the bugs and vulnerabilities in your code by feeding it a vast array of random or semi-random inputs.

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Go’s built-in fuzzing support makes it remarkably easy to integrate this valuable practice into your development workflow.

func ParseNumber(s string) (int, error) {
    // ... (your parsing logic here)
}

func FuzzParseNumber(f *testing.F) {
    f.Add("123", 456) // Seed corpus with some valid inputs
    f.Fuzz(func(t *testing.T, a, b string) {
        _, errA := ParseNumber(a)
        _, errB := ParseNumber(b)

        if (errA == nil) != (errB == nil) {
            t.Errorf("Inconsistent error for '%s' and '%s'", a, b)
        }
    })
}

In this example, FuzzParseNumber is a fuzz test that will automatically generate a variety of strings (a and b) and check if your ParseNumber function handles them consistently (i.e., either both succeed or both fail).

Let’s see an another example

package main

import (
    "fmt"
    "testing"
)

func ReverseString(s string) string {
    runes := []rune(s)
    for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
        runes[i], runes[j] = runes[j], runes[i]
    }
    return string(runes)
}

func FuzzReverseString(f…