main: remove deprecated uses of rand.Seed (#16074)

* main: remove deprecated uses of rand.Seed

go1.20 deprecates rand.Seed, and seeds the rand package
automatically. Remove cases where we seed the random package,
and cleanup the one case where we intentionally create a
known random source.

* cl: update cl

* mod: update go mod

.changelog/16074.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+core: Eliminate deprecated practice of seeding rand package
+```

client/servers/manager_internal_test.go

@@ -11,11 +11,6 @@ import (
 	"github.com/hashicorp/nomad/helper/testlog"
 )
 
-func init() {
-	// Seed the random number generator
-	rand.Seed(time.Now().UnixNano())
-}
-
 type fauxAddr struct {
 	Addr string
 }

command/agent/testagent.go

@@ -27,10 +27,6 @@ import (
 	"github.com/hashicorp/nomad/testutil"
 )
 
-func init() {
-	rand.Seed(time.Now().UnixNano()) // seed random number generator
-}
-
 // TempDir defines the base dir for temporary directories.
 var TempDir = os.TempDir()
 

go.mod

@@ -109,7 +109,6 @@ require (
 	github.com/rs/cors v1.8.3
 	github.com/ryanuber/columnize v2.1.2+incompatible
 	github.com/ryanuber/go-glob v1.0.0
-	github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529
 	github.com/shirou/gopsutil/v3 v3.22.12
 	github.com/shoenig/go-landlock v0.1.4
 	github.com/shoenig/test v0.6.1
@@ -252,6 +251,7 @@ require (
 	github.com/renier/xmlrpc v0.0.0-20170708154548-ce4a1a486c03 // indirect
 	github.com/rivo/uniseg v0.2.0 // indirect
 	github.com/rogpeppe/go-internal v1.9.0 // indirect
+	github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529 // indirect
 	github.com/seccomp/libseccomp-golang v0.10.0 // indirect
 	github.com/shopspring/decimal v1.2.0 // indirect
 	github.com/sirupsen/logrus v1.9.0 // indirect

main.go

@@ -22,7 +22,6 @@ import (
 	"github.com/hashicorp/nomad/command"
 	"github.com/hashicorp/nomad/version"
 	"github.com/mitchellh/cli"
-	"github.com/sean-/seed"
 )
 
 var (
@@ -74,19 +73,11 @@ var (
 	}
 )
 
-func init() {
-	seed.Init()
-}
-
 func main() {
 	os.Exit(Run(os.Args[1:]))
 }
 
 func Run(args []string) int {
-	return RunCustom(args)
-}
-
-func RunCustom(args []string) int {
 	// Create the meta object
 	metaPtr := new(command.Meta)
 	metaPtr.SetupUi(args)

nomad/periodic_test.go

@@ -618,7 +618,6 @@ func TestPeriodicDispatch_Complex(t *testing.T) {
 }
 
 func shuffle(jobs []*structs.Job) {
-	rand.Seed(time.Now().Unix())
 	for i := range jobs {
 		j := rand.Intn(len(jobs))
 		jobs[i], jobs[j] = jobs[j], jobs[i]

scheduler/spread_test.go

@@ -691,13 +691,13 @@ func generateUnevenRacks(t *testing.T, nodes int, rackCount int) map[string]int
 
 	// print this so that any future test flakes can be more easily
 	// reproduced
-	seed := time.Now().UnixNano()
-	rand.Seed(seed)
+	seed := time.Now().Unix()
+	random := rand.NewSource(seed)
 	t.Logf("nodes=%d racks=%d seed=%d\n", nodes, rackCount, seed)
 
 	racks := map[string]int{}
 	for i := 0; i < nodes; i++ {
-		idx := rand.Intn(len(rackNames))
+		idx := int(random.Int63()) % len(rackNames)
 		racks[rackNames[idx]]++
 	}
 	return racks