negentropy: fuzz testing, move accumulator to vector package.

nip77/negentropy/fuzz_test.go

@@ -0,0 +1,115 @@
+package negentropy_test
+
+import (
+	"crypto/sha256"
+	"encoding/binary"
+	"fmt"
+	"math/rand/v2"
+	"slices"
+	"sync"
+	"testing"
+
+	"github.com/nbd-wtf/go-nostr"
+	"github.com/nbd-wtf/go-nostr/nip77/negentropy"
+	"github.com/nbd-wtf/go-nostr/nip77/negentropy/storage/vector"
+	"github.com/stretchr/testify/require"
+)
+
+func FuzzWhatever(f *testing.F) {
+	var sectors uint = 1
+	var sectorSizeAvg uint = 10
+	var pctChance uint = 5
+	var frameSizeLimit uint = 0
+	f.Add(sectors, sectorSizeAvg, pctChance, frameSizeLimit)
+	f.Fuzz(func(t *testing.T, sectors uint, sectorSizeAvg uint, pctChance uint, frameSizeLimit uint) {
+		rand := rand.New(rand.NewPCG(1, 1000))
+		sectorSizeAvg += 1 // prevent divide by zero
+		frameSizeLimit += 4096
+		pctChance = pctChance % 100
+
+		// prepare the two sides
+		s1 := vector.New()
+		l1 := make([]string, 0, 500)
+		neg1 := negentropy.New(s1, int(frameSizeLimit))
+		s2 := vector.New()
+		l2 := make([]string, 0, 500)
+		neg2 := negentropy.New(s2, int(frameSizeLimit))
+
+		start := 0
+		for s := 0; s < int(sectors); s++ {
+			diff := rand.Uint() % sectorSizeAvg
+			if rand.IntN(2) == 0 {
+				diff = -diff
+			}
+			sectorSize := sectorSizeAvg + diff
+
+			for i := 0; i < int(sectorSize); i++ {
+				item := start + i
+
+				rnd := sha256.Sum256(binary.BigEndian.AppendUint64(nil, uint64(item)))
+				id := fmt.Sprintf("%x%056d", rnd[0:4], item)
+
+				if rand.IntN(100) < int(pctChance) {
+					s1.Insert(nostr.Timestamp(item), id)
+					l1 = append(l1, id)
+				}
+				if rand.IntN(100) < int(pctChance) {
+					id := fmt.Sprintf("%064d", item)
+					s2.Insert(nostr.Timestamp(item), id)
+					l2 = append(l2, id)
+				}
+			}
+
+			start += int(sectorSize)
+		}
+
+		// fmt.Println(neg1.Name(), "initial", l1)
+		// fmt.Println(neg2.Name(), "initial", l2)
+
+		wg := sync.WaitGroup{}
+		wg.Add(2)
+		go func() {
+			for item := range neg1.Haves {
+				// fmt.Println("have", item)
+				l2 = append(l2, item)
+			}
+			wg.Done()
+		}()
+		go func() {
+			for item := range neg1.HaveNots {
+				// fmt.Println("havenot", item)
+				l1 = append(l1, item)
+			}
+			wg.Done()
+		}()
+
+		msg := neg1.Start()
+		next := neg2
+
+		for {
+			var err error
+			// fmt.Println(next.Name(), "handling", msg)
+			msg, err = next.Reconcile(msg)
+			if err != nil {
+				panic(err)
+			}
+
+			if msg == "" {
+				break
+			}
+
+			if next == neg1 {
+				next = neg2
+			} else {
+				next = neg1
+			}
+		}
+
+		wg.Wait()
+		slices.Sort(l1)
+		l1 = slices.Compact(l1)
+		slices.Sort(l2)
+		l2 = slices.Compact(l2)
+		require.ElementsMatch(t, l1, l2)
+	})
+}