gofuzz is a library for populating go objects with random values.
This is useful for testing:
- Do your project's objects really serialize/unserialize correctly in all cases?
- Is there an incorrectly formatted object that will cause your project to panic?
Import with import "github.com/google/gofuzz"
You can use it on single variables:
f := fuzz.New()
var myInt int
f.Fuzz(&myInt) // myInt gets a random value.You can use it on maps:
f := fuzz.New().NilChance(0).NumElements(1, 1)
var myMap map[ComplexKeyType]string
f.Fuzz(&myMap) // myMap will have exactly one element.Customize the chance of getting a nil pointer:
f := fuzz.New().NilChance(.5)
var fancyStruct struct {
A, B, C, D *string
}
f.Fuzz(&fancyStruct) // About half the pointers should be set.You can even customize the randomization completely if needed:
type MyEnum string
const (
A MyEnum = "A"
B MyEnum = "B"
)
type MyInfo struct {
Type MyEnum
AInfo *string
BInfo *string
}
f := fuzz.New().NilChance(0).Funcs(
func(e *MyInfo, c fuzz.Continue) {
switch c.Intn(2) {
case 0:
e.Type = A
c.Fuzz(&e.AInfo)
case 1:
e.Type = B
c.Fuzz(&e.BInfo)
}
},
)
var myObject MyInfo
f.Fuzz(&myObject) // Type will correspond to whether A or B info is set.See more examples in example_test.go.
You can use this library for easier go-fuzzing.
go-fuzz provides the user a byte-slice, which should be converted to different inputs
for the tested function. This library can help convert the byte slice. Consider for
example a fuzz test for a the function mypackage.MyFunc that takes an int arguments:
// +build gofuzz
package mypackage
import fuzz "github.com/google/gofuzz"
func Fuzz(data []byte) int {
var i int
fuzz.NewFromGoFuzz(data).Fuzz(&i)
MyFunc(i)
return 0
}Happy testing!