Lower minimum version to 1.21

.github/workflows/go.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go-version: [ '1.22.x', '1.23.x' ]
+        go-version: [ '1.21.x', '1.22.x', '1.23.x' ]
 
     steps:
       - uses: actions/checkout@v4

bench_test.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"github.com/stretchr/testify/require"
 	tw "github.com/zolstein/type-walk"
-	"math/rand/v2"
+	"math/rand"
 	"reflect"
 	"runtime"
 	"strconv"
@@ -26,7 +26,7 @@ func BenchmarkSimpleJsonSerialize(b *testing.B) {
 
 	toSerialize := make([]*Outer, 100)
 	for i := range toSerialize {
-		inners := make([]*Inner, rand.N(10))
+		inners := make([]*Inner, rand.Intn(10))
 		for j := range inners {
 			inners[j] = &Inner{
 				D: rand.Int(),
@@ -62,7 +62,7 @@ func BenchmarkSimpleJsonSerialize(b *testing.B) {
 			}
 		case reflect.Slice:
 			bb.WriteRune('[')
-			for i := range v.Len() {
+			for i := 0; i < v.Len(); i++ {
 				if i > 0 {
 					bb.WriteRune(',')
 				}
@@ -72,7 +72,7 @@ func BenchmarkSimpleJsonSerialize(b *testing.B) {
 		case reflect.Struct:
 			bb.WriteRune('{')
 			t := v.Type()
-			for i := range t.NumField() {
+			for i := 0; i < t.NumField(); i++ {
 				if i > 0 {
 					bb.WriteRune(',')
 				}
@@ -93,7 +93,7 @@ func BenchmarkSimpleJsonSerialize(b *testing.B) {
 		runtime.GC()
 		b.ResetTimer()
 		b.ReportAllocs()
-		for range b.N {
+		for i := 0; i < b.N; i++ {
 			bb.Reset()
 			serializeReflect(reflect.ValueOf(toSerialize))
 			bs := bb.Bytes()
@@ -121,7 +121,7 @@ func BenchmarkSimpleJsonSerialize(b *testing.B) {
 	register.RegisterCompileSliceFn(func(r reflect.Type) tw.WalkSliceFn[*bytes.Buffer] {
 		return func(ctx *bytes.Buffer, s tw.Slice[*bytes.Buffer]) error {
 			bb.WriteRune('[')
-			for i := range s.Len() {
+			for i := 0; i < s.Len(); i++ {
 				if i > 0 {
 					bb.WriteRune(',')
 				}
@@ -142,7 +142,7 @@ func BenchmarkSimpleJsonSerialize(b *testing.B) {
 		}
 		return func(ctx *bytes.Buffer, s tw.Struct[*bytes.Buffer]) error {
 			bb.WriteRune('{')
-			for i := range s.NumFields() {
+			for i := 0; i < s.NumFields(); i++ {
 				if i > 0 {
 					bb.WriteRune(',')
 				}
@@ -183,7 +183,7 @@ func BenchmarkSimpleJsonSerialize(b *testing.B) {
 		runtime.GC()
 		b.ResetTimer()
 		b.ReportAllocs()
-		for range b.N {
+		for i := 0; i < b.N; i++ {
 			serializeTypeWalk(toSerializePtr)
 			bs := bb.Bytes()
 			_ = bs
@@ -193,9 +193,9 @@ func BenchmarkSimpleJsonSerialize(b *testing.B) {
 
 func randString(length int) string {
 	var letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
-	bs := make([]byte, rand.N(length))
+	bs := make([]byte, rand.Intn(length))
 	for i := range bs {
-		bs[i] = letters[rand.N(len(letters))]
+		bs[i] = letters[rand.Intn(len(letters))]
 	}
 	return string(bs)
 }

go.mod

@@ -1,6 +1,6 @@
 module github.com/zolstein/type-walk
 
-go 1.22
+go 1.21
 
 require (
 	github.com/goccy/go-reflect v1.2.0

walk.go

@@ -55,7 +55,8 @@ type Walker[Ctx any] struct {
 // Any new functions that are added to the register after calling NewWalker will not be used by the returned Walker.
 func NewWalker[Ctx any](register *Register[Ctx]) *Walker[Ctx] {
 	typeFns := make(map[g_reflect.Type]*walkFn[Ctx], len(register.typeFns))
-	for _, e := range register.typeFns {
+	for i := range register.typeFns {
+		e := &register.typeFns[i]
 		typeFns[e.t] = &e.fn
 	}
 	return &Walker[Ctx]{

walk_test.go

@@ -316,7 +316,7 @@ func TestRegisterCompileArrayFn(t *testing.T) {
 	register.RegisterCompileArrayFn(func(typ reflect.Type) tw.WalkArrayFn[*strings.Builder] {
 		return func(ctx *strings.Builder, aw tw.Array[*strings.Builder]) error {
 			ctx.WriteRune('[')
-			for i := range aw.Len() {
+			for i := 0; i < aw.Len(); i++ {
 				if i > 0 {
 					ctx.WriteRune(',')
 				}
@@ -363,7 +363,7 @@ func TestRegisterCompileSliceFn(t *testing.T) {
 				return nil
 			}
 			ctx.WriteRune('[')
-			for i := range sw.Len() {
+			for i := 0; i < sw.Len(); i++ {
 				if i > 0 {
 					ctx.WriteRune(',')
 				}
@@ -740,7 +740,7 @@ func settableSliceHelper(t *testing.T) {
 		})
 		register.RegisterCompileSliceFn(func(typ reflect.Type) tw.WalkSliceFn[struct{}] {
 			return func(ctx struct{}, s tw.Slice[struct{}]) error {
-				for i := range s.Len() {
+				for i := 0; i < s.Len(); i++ {
 					err := s.Walk(ctx, i)
 					if err != nil {
 						return err
@@ -792,7 +792,7 @@ func settableArrayHelper(t *testing.T) {
 		})
 		register.RegisterCompileArrayFn(func(typ reflect.Type) tw.WalkArrayFn[struct{}] {
 			return func(ctx struct{}, a tw.Array[struct{}]) error {
-				for i := range a.Len() {
+				for i := 0; i < a.Len(); i++ {
 					err := a.Walk(ctx, i)
 					if err != nil {
 						return err
@@ -844,11 +844,11 @@ func settableStructHelper(t *testing.T) {
 			return nil
 		})
 		register.RegisterCompileStructFn(func(typ reflect.Type, register tw.StructFieldRegister) tw.WalkStructFn[struct{}] {
-			for i := range typ.NumField() {
+			for i := 0; i < typ.NumField(); i++ {
 				register.RegisterField(i)
 			}
 			return func(ctx struct{}, s tw.Struct[struct{}]) error {
-				for i := range s.NumFields() {
+				for i := 0; i < s.NumFields(); i++ {
 					err := s.Walk(ctx, i)
 					if err != nil {
 						return err