From 237719bb8d401f2b600660b4f7ea025c9e7c1d91 Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Thu, 20 Aug 2026 15:02:47 +0100
Subject: [PATCH] build: modernize with "go fix -slicesbackward": use
 slices.Backward

---
 fs/operations/operations.go | 8 ++++----
 fs/sync/sync.go             | 3 +--
 fs/sync/sync_test.go        | 4 ++--
 fstest/fstest.go            | 4 ++--
 fstest/run.go               | 4 ++--
 5 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/fs/operations/operations.go b/fs/operations/operations.go
index b211d5154..b3b1ba5df 100644
--- a/fs/operations/operations.go
+++ b/fs/operations/operations.go
@@ -17,6 +17,7 @@ import (
 	"path"
 	"path/filepath"
 	"runtime"
+	"slices"
 	"sort"
 	"strconv"
 	"strings"
@@ -1569,8 +1570,7 @@ func Rmdirs(ctx context.Context, f fs.Fs, dir string, leaveRoot bool) error {
 
 	errCount := errcount.New()
 	// Delete all directories at the same level in parallel
-	for level := len(toDelete) - 1; level >= 0; level-- {
-		dirs := toDelete[level]
+	for level, dirs := range slices.Backward(toDelete) {
 		if len(dirs) == 0 {
 			continue
 		}
@@ -2511,8 +2511,8 @@ func DirMove(ctx context.Context, f fs.Fs, srcRemote, dstRemote string) (err err
 	}
 
 	// Remove the source directories in reverse order
-	for i := len(dirs) - 1; i >= 0; i-- {
-		err := f.Rmdir(ctx, dirs[i])
+	for _, dir := range slices.Backward(dirs) {
+		err := f.Rmdir(ctx, dir)
 		if err != nil {
 			return fmt.Errorf("RenameDir rmdir: %w", err)
 		}
diff --git a/fs/sync/sync.go b/fs/sync/sync.go
index 4892204ea..d53ac741c 100644
--- a/fs/sync/sync.go
+++ b/fs/sync/sync.go
@@ -684,8 +684,7 @@ func (s *syncCopyMove) deleteEmptyDirectories(ctx context.Context, f fs.Fs, entr
 	sort.Sort(entries)
 	var errorCount int
 	var okCount int
-	for i := len(entries) - 1; i >= 0; i-- {
-		entry := entries[i]
+	for _, entry := range slices.Backward(entries) {
 		dir, ok := entry.(fs.Directory)
 		if ok {
 			// TryRmdir only deletes empty directories
diff --git a/fs/sync/sync_test.go b/fs/sync/sync_test.go
index dbdfd6ec7..0a1f5a0eb 100644
--- a/fs/sync/sync_test.go
+++ b/fs/sync/sync_test.go
@@ -11,6 +11,7 @@ import (
 	"os"
 	"os/exec"
 	"runtime"
+	"slices"
 	"sort"
 	"strings"
 	"testing"
@@ -564,8 +565,7 @@ func TestSyncSetDelayedModTimes(t *testing.T) {
 
 	// Timestamp the directories in reverse order
 	ts := t1
-	for i := len(dirs) - 1; i >= 0; i-- {
-		dir := dirs[i]
+	for _, dir := range slices.Backward(dirs) {
 		_, err := operations.SetDirModTime(ctx, r.Flocal, nil, dir, ts)
 		require.NoError(t, err)
 		ts = ts.Add(time.Minute)
diff --git a/fstest/fstest.go b/fstest/fstest.go
index a0205a1c9..2267b0b43 100644
--- a/fstest/fstest.go
+++ b/fstest/fstest.go
@@ -15,6 +15,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"runtime"
+	"slices"
 	"sort"
 	"strings"
 	"testing"
@@ -515,8 +516,7 @@ func Purge(f fs.Fs) {
 			return nil
 		})
 		sort.Strings(dirs)
-		for i := len(dirs) - 1; i >= 0; i-- {
-			dir := dirs[i]
+		for _, dir := range slices.Backward(dirs) {
 			fs.Debugf(f, "Purge dir %q", dir)
 			err := f.Rmdir(ctx, dir)
 			if err != nil {
diff --git a/fstest/run.go b/fstest/run.go
index 7ac23e433..d5c25f263 100644
--- a/fstest/run.go
+++ b/fstest/run.go
@@ -33,6 +33,7 @@ import (
 	"os"
 	"path"
 	"path/filepath"
+	"slices"
 	"sort"
 	"testing"
 	"time"
@@ -181,8 +182,7 @@ func newRunIndividual(t *testing.T, individual bool) *Run {
 			}
 			require.NoError(t, err)
 			sort.Strings(toDelete)
-			for i := len(toDelete) - 1; i >= 0; i-- {
-				dir := toDelete[i]
+			for _, dir := range slices.Backward(toDelete) {
 				_ = Retry(t, fmt.Sprintf("removing dir %q", dir), func() error {
 					return r.Fremote.Rmdir(ctx, dir)
 				})