Files
go-cuckoo/cuckoo_fuzz_test.go
M.V. Hutz 395a3560c7 refactor: constructors, update docs
- NewCustomTable -> NewCustom
- NewTableBy -> NewBy
- NewTable -> New
2026-04-04 12:27:53 +02:00

93 lines
2.0 KiB
Go

package cuckoo_test
import (
"fmt"
"maps"
"os"
"testing"
"github.com/stretchr/testify/assert"
go_fuzz_utils "github.com/trailofbits/go-fuzz-utils"
"git.maximhutz.com/tools/go-cuckoo"
)
func offsetHash(seed uint32) cuckoo.Hash[uint32] {
return func(x uint32) uint64 {
v := uint64(x) ^ uint64(seed)
v = (v ^ (v >> 30)) * 0xbf58476d1ce4e5b9
v = (v ^ (v >> 27)) * 0x94d049bb133111eb
return v ^ (v >> 31)
}
}
type fuzzStep struct {
drop bool
key, value uint32
}
type fuzzScenario struct {
seedA, seedB uint32
capacity, growthFactor uint8
steps []fuzzStep
}
func FuzzInsertLookup(f *testing.F) {
f.Fuzz(func(t *testing.T, data []byte) {
var scenario fuzzScenario
assert := assert.New(t)
if tp, err := go_fuzz_utils.NewTypeProvider(data); err != nil {
return
} else if err := tp.Fill(&scenario); err != nil {
return
}
seedA, seedB := scenario.seedA, scenario.seedB
growthFactor := max(2, int(scenario.growthFactor))
capacity := int(scenario.capacity)
// If they are the same number, the hashes will clash, always causing an
// error.
if seedA == seedB {
t.Skip()
}
fmt.Fprintf(os.Stderr, "seedA=%d seedB=%d capacity=%d growthFactor=%d\n",
seedA, seedB, capacity, growthFactor)
actual := cuckoo.NewCustom[uint32, uint32](
offsetHash(seedA),
offsetHash(seedB),
func(a, b uint32) bool { return a == b },
cuckoo.Capacity(capacity),
cuckoo.GrowthFactor(growthFactor),
)
expected := map[uint32]uint32{}
for _, step := range scenario.steps {
if step.drop {
err := actual.Drop(step.key)
assert.NoError(err)
delete(expected, step.key)
_, err = actual.Get(step.key)
assert.Error(err)
} else {
err := actual.Put(step.key, step.value)
assert.NoError(err)
expected[step.key] = step.value
found, err := actual.Get(step.key)
assert.NoError(err)
assert.Equal(step.value, found)
}
assert.Equal(expected, maps.Collect(actual.Entries()))
}
})
}