Avoid using deprecated global rand functions

crdt.go

@@ -55,9 +55,7 @@ var (
 	ErrNoMoreBroadcast = errors.New("receiving blocks aborted since no new blocks will be broadcasted")
 )
 
-func init() {
-	rand.Seed(time.Now().UnixNano())
-}
+var randGen = rand.New(rand.NewSource(time.Now().UnixNano()))
 
 // A Broadcaster provides a way to send (notify) an opaque payload to
 // all replicas and to retrieve payloads broadcasted.
@@ -467,7 +465,7 @@ func randomizeInterval(d time.Duration) time.Duration {
 	// 30% of the configured interval
 	leeway := (d * 30 / 100)
 	// A random number between -leeway|+leeway
-	randomInterval := time.Duration(rand.Int63n(int64(leeway*2))) - leeway
+	randomInterval := time.Duration(randGen.Int63n(int64(leeway*2))) - leeway
 	return d + randomInterval
 }
 

crdt_test.go

@@ -3,7 +3,6 @@ package crdt
 import (
 	"context"
 	"fmt"
-	"math/rand"
 	"os"
 	"sync"
 	"sync/atomic"
@@ -36,7 +35,6 @@ const (
 var store int = mapStore
 
 func init() {
-	rand.Seed(time.Now().UnixNano())
 	dstest.ElemCount = 10
 }
 
@@ -122,15 +120,15 @@ func newBroadcasters(t testing.TB, n int) ([]*mockBroadcaster, context.CancelFun
 func (mb *mockBroadcaster) Broadcast(data []byte) error {
 	var wg sync.WaitGroup
 	for i, ch := range mb.chans {
-		n := rand.Intn(100)
+		n := randGen.Intn(100)
 		if n < mb.dropProb {
 			continue
 		}
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
 			// randomize when we send a little bit
-			if rand.Intn(100) < 30 {
+			if randGen.Intn(100) < 30 {
 				// Sleep for a very small time that will
 				// effectively be pretty random
 				time.Sleep(time.Nanosecond)
@@ -316,7 +314,7 @@ func TestCRDTReplication(t *testing.T) {
 	for i := 0; i < nItems; i++ {
 		k := ds.RandomKey()
 		v := []byte(fmt.Sprintf("%d", i))
-		n := rand.Intn(len(replicas))
+		n := randGen.Intn(len(replicas))
 		err := replicas[n].Put(ctx, k, v)
 		if err != nil {
 			t.Fatal(err)
@@ -357,7 +355,7 @@ func TestCRDTReplication(t *testing.T) {
 
 	// give a new value for each item
 	for _, r := range rest {
-		n := rand.Intn(len(replicas))
+		n := randGen.Intn(len(replicas))
 		err := replicas[n].Put(ctx, ds.NewKey(r.Key), []byte("hola"))
 		if err != nil {
 			t.Error(err)

heads_test.go

@@ -3,7 +3,6 @@ package crdt
 import (
 	"bytes"
 	"context"
-	"math/rand"
 	"reflect"
 	"sort"
 	"testing"
@@ -33,7 +32,7 @@ func newTestHeads(t *testing.T) *heads {
 func newCID(t *testing.T) cid.Cid {
 	t.Helper()
 	var buf [32]byte
-	_, _ = rand.Read(buf[:])
+	_, _ = randGen.Read(buf[:])
 
 	mh, err := multihash.Sum(buf[:], multihash.SHA2_256, -1)
 	if err != nil {
@@ -57,7 +56,7 @@ func TestHeadsBasic(t *testing.T) {
 	cidHeights := make(map[cid.Cid]uint64)
 	numHeads := 5
 	for i := 0; i < numHeads; i++ {
-		c, height := newCID(t), uint64(rand.Int())
+		c, height := newCID(t), uint64(randGen.Int())
 		cidHeights[c] = height
 		err := heads.Add(ctx, c, height)
 		if err != nil {
@@ -68,7 +67,7 @@ func TestHeadsBasic(t *testing.T) {
 	assertHeads(t, heads, cidHeights)
 
 	for c := range cidHeights {
-		newC, newHeight := newCID(t), uint64(rand.Int())
+		newC, newHeight := newCID(t), uint64(randGen.Int())
 		err := heads.Replace(ctx, c, newC, newHeight)
 		if err != nil {
 			t.Fatal(err)