fix(chunker): EncodeUnicodeBMP on chunker

Author: ci7lus

backend/box/box.go

@@ -356,6 +356,11 @@ func (f *Fs) Features() *fs.Features {
 	return f.features
 }
 
+// Encoder returns the encoder for this Fs
+func (f *Fs) Encoder() encoder.Encoder {
+	return f.opt.Enc
+}
+
 // parsePath parses a box 'url'
 func parsePath(path string) (root string) {
 	root = strings.Trim(path, "/")

backend/chunker/chunker.go

@@ -78,6 +78,13 @@ import (
 // Metadata format v1 does not define any control chunk types,
 // they are currently ignored aka reserved.
 // In future they can be used to implement resumable uploads etc.
+// Encoderer is an optional interface for Fs to return its encoder.
+// This is used to handle backends that encode file names in a way that
+// might cause issues with chunker's file name matching (e.g., EncodeUnicodeBMP).
+type Encoderer interface {
+	Encoder() encoder.Encoder
+}
+
 const (
 	ctrlTypeRegStr   = `[a-z][a-z0-9]{2,6}`
 	tempSuffixFormat = `_%04s`
@@ -2552,6 +2559,16 @@ func (f *Fs) Features() *fs.Features {
 	return f.features
 }
 
+func (f *Fs) Encoder() encoder.Encoder {
+	var baseEncoder encoder.Encoder
+	if do, ok := f.base.(Encoderer); ok {
+		baseEncoder = do.Encoder()
+	} else {
+		baseEncoder = encoder.Identity()
+	}
+	return baseEncoder
+}
+
 // String returns a description of the FS
 func (f *Fs) String() string {
 	return fmt.Sprintf("Chunked '%s:%s'", f.name, f.root)

fs/march/march.go

@@ -15,6 +15,7 @@ import (
 	"github.com/rclone/rclone/fs/filter"
 	"github.com/rclone/rclone/fs/list"
 	"github.com/rclone/rclone/fs/walk"
+	"github.com/rclone/rclone/lib/encoder"
 	"github.com/rclone/rclone/lib/transform"
 	"golang.org/x/text/unicode/norm"
 )
@@ -80,6 +81,10 @@ func (m *March) init(ctx context.Context) {
 	}
 }
 
+type Encoderer interface {
+	Encoder() encoder.Encoder
+}
+
 // srcOrDstKey turns a directory entry into a sort key using the defined transforms.
 func (m *March) srcOrDstKey(entry fs.DirEntry, isSrc bool) string {
 	if entry == nil {
@@ -89,6 +94,12 @@ func (m *March) srcOrDstKey(entry fs.DirEntry, isSrc bool) string {
 	_, isDirectory := entry.(fs.Directory)
 	if isSrc {
 		name = transform.Path(m.Ctx, name, isDirectory)
+		// Encode src name using dst Fs encoder to normalize for comparison
+		// Interface check for backends that encode filenames (e.g., Box with EncodeUnicodeBMP)
+		if enc, ok := m.Fdst.(Encoderer); ok {
+			encoder := enc.Encoder()
+			name = encoder.ToStandardPath(encoder.FromStandardPath(name))
+		}
 	}
 	for _, transform := range m.transforms {
 		name = transform(name)