refactor: use slices.Backward to simplify the code

pipeline/forkhandler.go

@@ -1,6 +1,7 @@
 package pipeline
 
 import (
+	"slices"
 	"sync"
 
 	pbssinternal "github.com/streamingfast/substreams/pb/sf/substreams/intern/v2"
@@ -42,8 +43,8 @@ func (f *ForkHandler) joinReversibleOutputs(target *pbsubstreams.Clock, previous
 	defer f.mu.Unlock()
 
 	reversibleOutputs := f.reversibleOutputs[target.Id]
-	for i := len(previousClocks) - 1; i >= 0; i-- {
-		if clock := previousClocks[i]; clock != nil {
+	for _, v := range slices.Backward(previousClocks) {
+		if clock := v; clock != nil {
 			if outputs, found := f.reversibleOutputs[clock.Id]; found {
 				reversibleOutputs = append(reversibleOutputs, outputs...)
 				delete(f.reversibleOutputs, clock.Id)

pipeline/process_block.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"os"
 	"runtime/debug"
+	"slices"
 	"strconv"
 
 	"connectrpc.com/connect"
@@ -234,8 +235,7 @@ func (p *Pipeline) undoPartialStates() error {
 		return nil
 	}
 
-	for i := len(p.partialProcessingState.processedPartials) - 1; i >= 0; i-- {
-		clk := p.partialProcessingState.processedPartials[i]
+	for _, clk := range slices.Backward(p.partialProcessingState.processedPartials) {
 		if err := p.forkHandler.handleUndo(clk); err != nil {
 			return fmt.Errorf("reverting outputs: %w", err)
 		}

storage/store/delta.go

@@ -3,6 +3,7 @@ package store
 import (
 	"errors"
 	"fmt"
+	"slices"
 	"strings"
 
 	pbsubstreams "github.com/streamingfast/substreams/pb/sf/substreams/v1"
@@ -92,8 +93,7 @@ func storeTooBigError(storeName string, size, limit uint64) error {
 func (b *baseStore) ApplyDeltasReverse(deltas []*pbsubstreams.StoreDelta) {
 	b.recentlyDeletedPrefixes.Clear() // whenever we have an undo block, we clear this cache to avoid any bug
 
-	for i := len(deltas) - 1; i >= 0; i-- {
-		delta := deltas[i]
+	for _, delta := range slices.Backward(deltas) {
 
 		newSize := uint64(len(delta.NewValue))
 		oldSize := uint64(len(delta.OldValue))

storage/store/value_get.go

@@ -3,6 +3,7 @@ package store
 import (
 	"bytes"
 	"fmt"
+	"slices"
 
 	pbsubstreams "github.com/streamingfast/substreams/pb/sf/substreams/v1"
 )
@@ -63,8 +64,7 @@ func (b *baseStore) HasFirst(key string) bool {
 }
 
 func (b *baseStore) getLast(key string) ([]byte, bool) {
-	for i := len(b.deltas) - 1; i >= 0; i-- {
-		delta := b.deltas[i]
+	for _, delta := range slices.Backward(b.deltas) {
 		if delta.Key != key {
 			continue
 		}
@@ -96,8 +96,7 @@ func (b *baseStore) GetLast(key string) ([]byte, bool) {
 }
 
 func (b *baseStore) HasLast(key string) bool {
-	for i := len(b.deltas) - 1; i >= 0; i-- {
-		delta := b.deltas[i]
+	for _, delta := range slices.Backward(b.deltas) {
 		if delta.Key != key {
 			continue
 		}
@@ -119,8 +118,7 @@ func (b *baseStore) HasLast(key string) bool {
 func (b *baseStore) getAt(ord uint64, key string) (out []byte, found bool) {
 	out, found = b.getLast(key)
 
-	for i := len(b.deltas) - 1; i >= 0; i-- {
-		delta := b.deltas[i]
+	for _, delta := range slices.Backward(b.deltas) {
 		if delta.Ordinal <= ord {
 			break
 		}
@@ -161,8 +159,7 @@ func (b *baseStore) GetAt(ord uint64, key string) (out []byte, found bool) {
 func (b *baseStore) HasAt(ord uint64, key string) bool {
 	_, found := b.GetFirst(key)
 
-	for i := len(b.deltas) - 1; i >= 0; i-- {
-		delta := b.deltas[i]
+	for _, delta := range slices.Backward(b.deltas) {
 		if delta.Ordinal <= ord {
 			break
 		}

tui2/pages/output/output.go

@@ -305,8 +305,7 @@ func (o *Output) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			o.statusBar.SetBytesRepresentation(o.bytesRepresentation)
 			o.setOutputViewContent(true)
 		case "N":
-			for i := len(o.searchMatchingOutputViewOffsets) - 1; i >= 0; i-- {
-				pos := o.searchMatchingOutputViewOffsets[i]
+			for _, pos := range slices.Backward(o.searchMatchingOutputViewOffsets) {
 				if pos < o.outputView.YOffset {
 					o.outputView.YOffset = pos
 					break
@@ -554,8 +553,7 @@ func (o *Output) jumpToPreviousMatchingBlock() tea.Cmd {
 	activeBlock := o.active.BlockNum
 	blocks := o.searchBlockNumsWithMatches
 	return func() tea.Msg {
-		for i := len(blocks) - 1; i >= 0; i-- {
-			block := blocks[i]
+		for _, block := range slices.Backward(blocks) {
 			if block < activeBlock {
 				return blockselect.BlockChangedMsg(block)
 			}