bisync: refactor normalization code, fix deltas - fixes #7270

Refactored the case / unicode normalization logic to be much more efficient,
 and fix the last outstanding issue from #7270. Before this change, we were
 doing lots of for loops and re-normalizing strings we had already normalized
 earlier. Now, we leave the normalizing entirely to March and avoid
 re-transforming later, which seems to make a large difference in terms of
 performance.

cmd/bisync/bilib/names.go

@@ -59,3 +59,27 @@ func SaveList(list []string, path string) error {
 	}
 	return os.WriteFile(path, buf.Bytes(), PermSecure)
 }
+
+// AliasMap comprises a pair of names that are not equal but treated as equal for comparison purposes
+// For example, when normalizing unicode and casing
+// This helps reduce repeated normalization functions, which really slow things down
+type AliasMap map[string]string
+
+// Add adds new pair to the set, in both directions
+func (am AliasMap) Add(name1, name2 string) {
+	if name1 != name2 {
+		am[name1] = name2
+		am[name2] = name1
+	}
+}
+
+// Alias returns the alternate version, if any, else the original.
+func (am AliasMap) Alias(name1 string) string {
+	// note: we don't need to check normalization settings, because we already did it in March.
+	// the AliasMap will only exist if March paired up two unequal filenames.
+	name2, ok := am[name1]
+	if ok {
+		return name2
+	}
+	return name1
+}

cmd/bisync/deltas.go

@@ -16,6 +16,7 @@ import (
 	"github.com/rclone/rclone/fs/accounting"
 	"github.com/rclone/rclone/fs/filter"
 	"github.com/rclone/rclone/fs/operations"
+	"golang.org/x/text/unicode/norm"
 )
 
 // delta
@@ -240,6 +241,9 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 
 	ctxMove := b.opt.setDryRun(ctx)
 
+	// update AliasMap for deleted files, as march does not know about them
+	b.updateAliases(ctx, ds1, ds2)
+
 	// efficient isDir check
 	// we load the listing just once and store only the dirs
 	dirs1, dirs1Err := b.listDirsOnly(1)
@@ -270,14 +274,24 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 	ctxCheck, filterCheck := filter.AddConfig(ctxNew)
 
 	for _, file := range ds1.sort() {
+		alias := b.aliases.Alias(file)
 		d1 := ds1.deltas[file]
 		if d1.is(deltaOther) {
-			d2 := ds2.deltas[file]
+			d2, in2 := ds2.deltas[file]
+			if !in2 && file != alias {
+				d2 = ds2.deltas[alias]
+			}
 			if d2.is(deltaOther) {
-				if err := filterCheck.AddFile(file); err != nil {
+				checkit := func(filename string) {
+					if err := filterCheck.AddFile(filename); err != nil {
 						fs.Debugf(nil, "Non-critical error adding file to list of potential conflicts to check: %s", err)
 					} else {
-					fs.Debugf(nil, "Added file to list of potential conflicts to check: %s", file)
+						fs.Debugf(nil, "Added file to list of potential conflicts to check: %s", filename)
+					}
+				}
+				checkit(file)
+				if file != alias {
+					checkit(alias)
 				}
 			}
 		}
@@ -287,12 +301,17 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 	matches, err := b.checkconflicts(ctxCheck, filterCheck, b.fs1, b.fs2)
 
 	for _, file := range ds1.sort() {
+		alias := b.aliases.Alias(file)
 		p1 := path1 + file
-		p2 := path2 + file
+		p2 := path2 + alias
 		d1 := ds1.deltas[file]
 
 		if d1.is(deltaOther) {
 			d2, in2 := ds2.deltas[file]
+			// try looking under alternate name
+			if !in2 && file != alias {
+				d2, in2 = ds2.deltas[alias]
+			}
 			if !in2 {
 				b.indent("Path1", p2, "Queue copy to Path2")
 				copy1to2.Add(file)
@@ -304,15 +323,26 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 				b.indent("!WARNING", file, "New or changed in both paths")
 
 				//if files are identical, leave them alone instead of renaming
-				if dirs1.has(file) && dirs2.has(file) {
+				if (dirs1.has(file) || dirs1.has(alias)) && (dirs2.has(file) || dirs2.has(alias)) {
 					fs.Debugf(nil, "This is a directory, not a file. Skipping equality check and will not rename: %s", file)
 					ls1.getPut(file, skippedDirs1)
 					ls2.getPut(file, skippedDirs2)
 				} else {
 					equal := matches.Has(file)
+					if !equal {
+						equal = matches.Has(alias)
+					}
 					if equal {
+						if ciCheck.FixCase && file != alias {
+							// the content is equal but filename still needs to be FixCase'd, so copy1to2
+							// the Path1 version is deemed "correct" in this scenario
+							fs.Infof(alias, "Files are equal but will copy anyway to fix case to %s", file)
+							copy1to2.Add(file)
+						} else {
 							fs.Infof(nil, "Files are equal! Skipping: %s", file)
 							renameSkipped.Add(file)
+							renameSkipped.Add(alias)
+						}
 					} else {
 						fs.Debugf(nil, "Files are NOT equal: %s", file)
 						b.indent("!Path1", p1+"..path1", "Renaming Path1 copy")
@@ -330,17 +360,17 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 						copy1to2.Add(file + "..path1")
 
 						b.indent("!Path2", p2+"..path2", "Renaming Path2 copy")
-						if err = operations.MoveFile(ctxMove, b.fs2, b.fs2, file+"..path2", file); err != nil {
+						if err = operations.MoveFile(ctxMove, b.fs2, b.fs2, alias+"..path2", alias); err != nil {
-							err = fmt.Errorf("path2 rename failed for %s: %w", file, err)
+							err = fmt.Errorf("path2 rename failed for %s: %w", alias, err)
 							return
 						}
 						if b.opt.DryRun {
-							renameSkipped.Add(file)
+							renameSkipped.Add(alias)
 						} else {
-							renamed2.Add(file)
+							renamed2.Add(alias)
 						}
 						b.indent("!Path2", p1+"..path2", "Queue copy to Path1")
-						copy2to1.Add(file + "..path2")
+						copy2to1.Add(alias + "..path2")
 					}
 				}
 				handled.Add(file)
@@ -348,6 +378,15 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 		} else {
 			// Path1 deleted
 			d2, in2 := ds2.deltas[file]
+			// try looking under alternate name
+			fs.Debugf(file, "alias: %s, in2: %v", alias, in2)
+			if !in2 && file != alias {
+				fs.Debugf(file, "looking for alias: %s", alias)
+				d2, in2 = ds2.deltas[alias]
+				if in2 {
+					fs.Debugf(file, "detected alias: %s", alias)
+				}
+			}
 			if !in2 {
 				b.indent("Path2", p2, "Queue delete")
 				delete2.Add(file)
@@ -359,15 +398,17 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 			} else if d2.is(deltaDeleted) {
 				handled.Add(file)
 				deletedonboth.Add(file)
+				deletedonboth.Add(alias)
 			}
 		}
 	}
 
 	for _, file := range ds2.sort() {
-		p1 := path1 + file
+		alias := b.aliases.Alias(file)
+		p1 := path1 + alias
 		d2 := ds2.deltas[file]
 
-		if handled.Has(file) {
+		if handled.Has(file) || handled.Has(alias) {
 			continue
 		}
 		if d2.is(deltaOther) {
@@ -381,17 +422,11 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 		}
 	}
 
-	// find alternate names according to normalization settings
-	altNames1to2 := bilib.Names{}
-	altNames2to1 := bilib.Names{}
-	b.findAltNames(ctx, b.fs1, copy2to1, b.newListing1, altNames2to1)
-	b.findAltNames(ctx, b.fs2, copy1to2, b.newListing2, altNames1to2)
-
 	// Do the batch operation
 	if copy2to1.NotEmpty() {
 		changes1 = true
 		b.indent("Path2", "Path1", "Do queued copies to")
-		results2to1, err = b.fastCopy(ctx, b.fs2, b.fs1, copy2to1, "copy2to1", altNames2to1)
+		results2to1, err = b.fastCopy(ctx, b.fs2, b.fs1, copy2to1, "copy2to1")
 		if err != nil {
 			return
 		}
@@ -403,7 +438,7 @@ func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (change
 	if copy1to2.NotEmpty() {
 		changes2 = true
 		b.indent("Path1", "Path2", "Do queued copies to")
-		results1to2, err = b.fastCopy(ctx, b.fs1, b.fs2, copy1to2, "copy1to2", altNames1to2)
+		results1to2, err = b.fastCopy(ctx, b.fs1, b.fs2, copy1to2, "copy1to2")
 		if err != nil {
 			return
 		}
@@ -458,3 +493,65 @@ func (ds *deltaSet) excessDeletes() bool {
 		maxDelete, ds.deleted, ds.oldCount, ds.msg, quotePath(bilib.FsPath(ds.fs)))
 	return true
 }
+
+// normally we build the AliasMap from march results,
+// however, march does not know about deleted files, so need to manually check them for aliases
+func (b *bisyncRun) updateAliases(ctx context.Context, ds1, ds2 *deltaSet) {
+	ci := fs.GetConfig(ctx)
+	// skip if not needed
+	if ci.NoUnicodeNormalization && !ci.IgnoreCaseSync && !b.fs1.Features().CaseInsensitive && !b.fs2.Features().CaseInsensitive {
+		return
+	}
+	if ds1.deleted < 1 && ds2.deleted < 1 {
+		return
+	}
+
+	fs.Debugf(nil, "Updating AliasMap")
+
+	transform := func(s string) string {
+		if !ci.NoUnicodeNormalization {
+			s = norm.NFC.String(s)
+		}
+		// note: march only checks the dest, but we check both here
+		if ci.IgnoreCaseSync || b.fs1.Features().CaseInsensitive || b.fs2.Features().CaseInsensitive {
+			s = strings.ToLower(s)
+		}
+		return s
+	}
+
+	delMap1 := map[string]string{}  // [transformedname]originalname
+	delMap2 := map[string]string{}  // [transformedname]originalname
+	fullMap1 := map[string]string{} // [transformedname]originalname
+	fullMap2 := map[string]string{} // [transformedname]originalname
+
+	for _, name := range ls1.list {
+		fullMap1[transform(name)] = name
+	}
+	for _, name := range ls2.list {
+		fullMap2[transform(name)] = name
+	}
+
+	addDeletes := func(ds *deltaSet, delMap, fullMap map[string]string) {
+		for _, file := range ds.sort() {
+			d := ds.deltas[file]
+			if d.is(deltaDeleted) {
+				delMap[transform(file)] = file
+				fullMap[transform(file)] = file
+			}
+		}
+	}
+	addDeletes(ds1, delMap1, fullMap1)
+	addDeletes(ds2, delMap2, fullMap2)
+
+	addAliases := func(delMap, fullMap map[string]string) {
+		for transformedname, name := range delMap {
+			matchedName, found := fullMap[transformedname]
+			if found && name != matchedName {
+				fs.Debugf(name, "adding alias %s", matchedName)
+				b.aliases.Add(name, matchedName)
+			}
+		}
+	}
+	addAliases(delMap1, fullMap2)
+	addAliases(delMap2, fullMap1)
+}

cmd/bisync/listing.go

@@ -5,6 +5,7 @@ package bisync
 import (
 	"bufio"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -20,7 +21,6 @@ import (
 	"github.com/rclone/rclone/fs/hash"
 	"github.com/rclone/rclone/fs/operations"
 	"golang.org/x/exp/slices"
-	"golang.org/x/text/unicode/norm"
 )
 
 // ListingHeader defines first line of a listing
@@ -407,18 +407,6 @@ func ConvertPrecision(Modtime time.Time, dst fs.Fs) time.Time {
 	return Modtime
 }
 
-// ApplyTransforms handles unicode and case normalization
-func ApplyTransforms(ctx context.Context, dst fs.Fs, s string) string {
-	ci := fs.GetConfig(ctx)
-	if !ci.NoUnicodeNormalization {
-		s = norm.NFC.String(s)
-	}
-	if ci.IgnoreCaseSync || dst.Features().CaseInsensitive {
-		s = strings.ToLower(s)
-	}
-	return s
-}
-
 // modifyListing will modify the listing based on the results of the sync
 func (b *bisyncRun) modifyListing(ctx context.Context, src fs.Fs, dst fs.Fs, results []Results, queues queues, is1to2 bool) (err error) {
 	queue := queues.copy2to1
@@ -448,18 +436,6 @@ func (b *bisyncRun) modifyListing(ctx context.Context, src fs.Fs, dst fs.Fs, res
 		srcList.hash = src.Hashes().GetOne()
 		dstList.hash = dst.Hashes().GetOne()
 	}
-	dstListNew, err := b.loadListing(dstListing + "-new")
-	if err != nil {
-		return fmt.Errorf("cannot read new listing: %w", err)
-	}
-	// for resync only, dstListNew will be empty, so need to use results instead
-	if b.opt.Resync {
-		for _, result := range results {
-			if result.Name != "" && result.IsDst {
-				dstListNew.put(result.Name, result.Size, result.Modtime, result.Hash, "-", result.Flags)
-			}
-		}
-	}
 
 	srcWinners := newFileList()
 	dstWinners := newFileList()
@@ -471,6 +447,10 @@ func (b *bisyncRun) modifyListing(ctx context.Context, src fs.Fs, dst fs.Fs, res
 			continue
 		}
 
+		if result.AltName != "" {
+			b.aliases.Add(result.Name, result.AltName)
+		}
+
 		if result.Flags == "d" && !b.opt.CreateEmptySrcDirs {
 			continue
 		}
@@ -496,6 +476,7 @@ func (b *bisyncRun) modifyListing(ctx context.Context, src fs.Fs, dst fs.Fs, res
 		}
 	}
 
+	ci := fs.GetConfig(ctx)
 	updateLists := func(side string, winners, list *fileList) {
 		for _, queueFile := range queue.ToList() {
 			if !winners.has(queueFile) && list.has(queueFile) && !errors.has(queueFile) {
@@ -506,28 +487,17 @@ func (b *bisyncRun) modifyListing(ctx context.Context, src fs.Fs, dst fs.Fs, res
 				// copies to side
 				new := winners.get(queueFile)
 
-				// handle normalization according to settings
+				// handle normalization
-				ci := fs.GetConfig(ctx)
+				if side == "dst" {
-				if side == "dst" && (!ci.NoUnicodeNormalization || ci.IgnoreCaseSync || dst.Features().CaseInsensitive) {
+					alias := b.aliases.Alias(queueFile)
-					// search list for existing file that matches queueFile when normalized
+					if alias != queueFile {
-					normalizedName := ApplyTransforms(ctx, dst, queueFile)
-					matchFound := false
-					matchedName := ""
-					for _, filename := range dstListNew.list {
-						if ApplyTransforms(ctx, dst, filename) == normalizedName {
-							matchFound = true
-							matchedName = filename // original, not normalized
-							break
-						}
-					}
-					if matchFound && matchedName != queueFile {
 						// use the (non-identical) existing name, unless --fix-case
 						if ci.FixCase {
-							fs.Debugf(direction, "removing %s and adding %s as --fix-case was specified", matchedName, queueFile)
+							fs.Debugf(direction, "removing %s and adding %s as --fix-case was specified", alias, queueFile)
-							list.remove(matchedName)
+							list.remove(alias)
 						} else {
-							fs.Debugf(direction, "casing/unicode difference detected. using %s instead of %s", matchedName, queueFile)
+							fs.Debugf(direction, "casing/unicode difference detected. using %s instead of %s", alias, queueFile)
-							queueFile = matchedName
+							queueFile = alias
 						}
 					}
 				}
@@ -613,6 +583,16 @@ func (b *bisyncRun) modifyListing(ctx context.Context, src fs.Fs, dst fs.Fs, res
 	}
 
 	if filterRecheck.HaveFilesFrom() {
+		// also include any aliases
+		recheckFiles := filterRecheck.Files()
+		for recheckFile := range recheckFiles {
+			alias := b.aliases.Alias(recheckFile)
+			if recheckFile != alias {
+				if err := filterRecheck.AddFile(alias); err != nil {
+					fs.Debugf(alias, "error adding file to recheck filter: %v", err)
+				}
+			}
+		}
 		b.recheck(ctxRecheck, src, dst, srcList, dstList, is1to2)
 	}
 
@@ -661,7 +641,7 @@ func (b *bisyncRun) recheck(ctxRecheck context.Context, src, dst fs.Fs, srcList,
 	for _, srcObj := range srcObjs {
 		fs.Debugf(srcObj, "rechecking")
 		for _, dstObj := range dstObjs {
-			if srcObj.Remote() == dstObj.Remote() {
+			if srcObj.Remote() == dstObj.Remote() || srcObj.Remote() == b.aliases.Alias(dstObj.Remote()) {
 				if operations.Equal(ctxRecheck, srcObj, dstObj) || b.opt.DryRun {
 					putObj(srcObj, src, srcList)
 					putObj(dstObj, dst, dstList)
@@ -673,16 +653,24 @@ func (b *bisyncRun) recheck(ctxRecheck context.Context, src, dst fs.Fs, srcList,
 		}
 		// if srcObj not resolved by now (either because no dstObj match or files not equal),
 		// roll it back to old version, so it gets retried next time.
+		// skip and error during --resync, as rollback is not possible
 		if !slices.Contains(resolved, srcObj.Remote()) && !b.opt.DryRun {
+			if b.opt.Resync {
+				b.handleErr(srcObj, "Unable to rollback during --resync", errors.New("no dstObj match or files not equal"), true, false)
+			} else {
 				toRollback = append(toRollback, srcObj.Remote())
 			}
 		}
+	}
 	if len(toRollback) > 0 {
 		srcListing, dstListing := b.getListingNames(is1to2)
 		oldSrc, err := b.loadListing(srcListing + "-old")
 		b.handleErr(oldSrc, "error loading old src listing", err, true, true)
 		oldDst, err := b.loadListing(dstListing + "-old")
 		b.handleErr(oldDst, "error loading old dst listing", err, true, true)
+		if b.critical {
+			return
+		}
 
 		for _, item := range toRollback {
 			rollback(item, oldSrc, srcList)

cmd/bisync/march.go

@@ -15,6 +15,7 @@ var ls1 = newFileList()
 var ls2 = newFileList()
 var err error
 var firstErr error
+var marchAliasLock sync.Mutex
 var marchLsLock sync.Mutex
 var marchErrLock sync.Mutex
 var marchCtx context.Context
@@ -77,6 +78,9 @@ func (b *bisyncRun) DstOnly(o fs.DirEntry) (recurse bool) {
 // Match is called when object exists on both path1 and path2 (whether equal or not)
 func (b *bisyncRun) Match(ctx context.Context, o2, o1 fs.DirEntry) (recurse bool) {
 	fs.Debugf(o1, "both path1 and path2")
+	marchAliasLock.Lock()
+	b.aliases.Add(o1.Remote(), o2.Remote())
+	marchAliasLock.Unlock()
 	b.parse(o1, true)
 	b.parse(o2, false)
 	return isDir(o1)

cmd/bisync/operations.go

@@ -36,6 +36,7 @@ type bisyncRun struct {
 	listing2    string
 	newListing1 string
 	newListing2 string
+	aliases     bilib.AliasMap
 	opt         *Options
 	octx        context.Context
 	fctx        context.Context
@@ -90,6 +91,7 @@ func Bisync(ctx context.Context, fs1, fs2 fs.Fs, optArg *Options) (err error) {
 	b.listing2 = b.basePath + ".path2.lst"
 	b.newListing1 = b.listing1 + "-new"
 	b.newListing2 = b.listing2 + "-new"
+	b.aliases = bilib.AliasMap{}
 
 	// Handle lock file
 	lockFile := ""
@@ -448,7 +450,7 @@ func (b *bisyncRun) resync(octx, fctx context.Context) error {
 	}
 
 	fs.Infof(nil, "Resync updating listings")
-	b.saveOldListings()
+	b.saveOldListings() // may not exist, as this is --resync
 	b.replaceCurrentListings()
 
 	resultsToQueue := func(results []Results) bilib.Names {
@@ -496,31 +498,15 @@ func (b *bisyncRun) checkSync(listing1, listing2 string) error {
 		return fmt.Errorf("cannot read prior listing of Path2: %w", err)
 	}
 
-	transformList := func(files *fileList, fs fs.Fs) *fileList {
-		transformed := newFileList()
-		for _, file := range files.list {
-			f := files.get(file)
-			transformed.put(ApplyTransforms(b.fctx, fs, file), f.size, f.time, f.hash, f.id, f.flags)
-		}
-		return transformed
-	}
-
-	files1Transformed := transformList(files1, b.fs1)
-	files2Transformed := transformList(files2, b.fs2)
-
-	// DEBUG
-	fs.Debugf(nil, "files1Transformed: %v", files1Transformed)
-	fs.Debugf(nil, "files2Transformed: %v", files2Transformed)
-
 	ok := true
 	for _, file := range files1.list {
-		if !files2.has(file) && !files2Transformed.has(ApplyTransforms(b.fctx, b.fs1, file)) {
+		if !files2.has(file) && !files2.has(b.aliases.Alias(file)) {
 			b.indent("ERROR", file, "Path1 file not found in Path2")
 			ok = false
 		}
 	}
 	for _, file := range files2.list {
-		if !files1.has(file) && !files1Transformed.has(ApplyTransforms(b.fctx, b.fs2, file)) {
+		if !files1.has(file) && !files1.has(b.aliases.Alias(file)) {
 			b.indent("ERROR", file, "Path2 file not found in Path1")
 			ok = false
 		}
@@ -580,7 +566,7 @@ func (b *bisyncRun) handleErr(o interface{}, msg string, err error, critical, re
 			b.critical = true
 			fs.Errorf(o, "%s: %v", msg, err)
 		} else {
-			fs.Debugf(o, "%s: %v", msg, err)
+			fs.Infof(o, "%s: %v", msg, err)
 		}
 	}
 }

cmd/bisync/queue.go

@@ -22,6 +22,7 @@ type Results struct {
 	Src      string
 	Dst      string
 	Name     string
+	AltName  string
 	Size     int64
 	Modtime  time.Time
 	Hash     string
@@ -58,6 +59,21 @@ func resultName(result Results, side, src, dst fs.DirEntry) string {
 	return ""
 }
 
+// returns the opposite side's name, only if different
+func altName(name string, src, dst fs.DirEntry) string {
+	if src != nil && dst != nil {
+		if src.Remote() != dst.Remote() {
+			switch name {
+			case src.Remote():
+				return dst.Remote()
+			case dst.Remote():
+				return src.Remote()
+			}
+		}
+	}
+	return ""
+}
+
 // WriteResults is Bisync's LoggerFn
 func WriteResults(ctx context.Context, sigil operations.Sigil, src, dst fs.DirEntry, err error) {
 	lock.Lock()
@@ -77,6 +93,7 @@ func WriteResults(ctx context.Context, sigil operations.Sigil, src, dst fs.DirEn
 	for i, side := range fss {
 
 		result.Name = resultName(result, side, src, dst)
+		result.AltName = altName(result.Name, src, dst)
 		result.IsSrc = i == 0
 		result.IsDst = i == 1
 		result.Flags = "-"
@@ -129,7 +146,7 @@ func ReadResults(results io.Reader) []Results {
 	return slice
 }
 
-func (b *bisyncRun) fastCopy(ctx context.Context, fsrc, fdst fs.Fs, files bilib.Names, queueName string, altNames bilib.Names) ([]Results, error) {
+func (b *bisyncRun) fastCopy(ctx context.Context, fsrc, fdst fs.Fs, files bilib.Names, queueName string) ([]Results, error) {
 	if err := b.saveQueue(files, queueName); err != nil {
 		return nil, err
 	}
@@ -139,10 +156,9 @@ func (b *bisyncRun) fastCopy(ctx context.Context, fsrc, fdst fs.Fs, files bilib.
 		if err := filterCopy.AddFile(file); err != nil {
 			return nil, err
 		}
-	}
+		alias := b.aliases.Alias(file)
-	if altNames.NotEmpty() {
+		if alias != file {
-		for _, file := range altNames.ToList() {
+			if err := filterCopy.AddFile(alias); err != nil {
-			if err := filterCopy.AddFile(file); err != nil {
 				return nil, err
 			}
 		}
@@ -249,22 +265,3 @@ func (b *bisyncRun) saveQueue(files bilib.Names, jobName string) error {
 	queueFile := fmt.Sprintf("%s.%s.que", b.basePath, jobName)
 	return files.Save(queueFile)
 }
-
-func (b *bisyncRun) findAltNames(ctx context.Context, dst fs.Fs, queue bilib.Names, newListing string, altNames bilib.Names) {
-	ci := fs.GetConfig(ctx)
-	if queue.NotEmpty() && (!ci.NoUnicodeNormalization || ci.IgnoreCaseSync || b.fs1.Features().CaseInsensitive || b.fs2.Features().CaseInsensitive) {
-		// search list for existing file that matches queueFile when normalized
-		for _, queueFile := range queue.ToList() {
-			normalizedName := ApplyTransforms(ctx, dst, queueFile)
-			candidates, err := b.loadListing(newListing)
-			if err != nil {
-				fs.Errorf(candidates, "cannot read new listing: %v", err)
-			}
-			for _, filename := range candidates.list {
-				if ApplyTransforms(ctx, dst, filename) == normalizedName && filename != queueFile {
-					altNames.Add(filename) // original, not normalized
-				}
-			}
-		}
-	}
-}

cmd/bisync/testdata/test_normalization/golden/_testdir_path1.._testdir_path2.copy2to1.que

@@ -1,3 +1 @@
 "file1.txt"
-"folder/hello,WORLD!.txt"
-"folder/éééö.txt"

cmd/bisync/testdata/test_normalization/golden/_testdir_path1.._testdir_path2.path2.lst-new

@@ -1,5 +1,5 @@
 # bisync listing v1 from test
 -       19 md5:7fe98ed88552b828777d8630900346b8 - 2001-01-05T00:00:00.000000000+0000 "file1.txt"
--       19 md5:7fe98ed88552b828777d8630900346b8 - 2001-01-05T00:00:00.000000000+0000 "folder/hello,WORLD!.txt"
+-       19 md5:7fe98ed88552b828777d8630900346b8 - 2001-01-03T00:00:00.000000000+0000 "folder/hello,WORLD!.txt"
--       19 md5:7fe98ed88552b828777d8630900346b8 - 2001-01-05T00:00:00.000000000+0000 "folder/éééö.txt"
+-       19 md5:7fe98ed88552b828777d8630900346b8 - 2001-01-03T00:00:00.000000000+0000 "folder/éééö.txt"
 -       19 md5:7fe98ed88552b828777d8630900346b8 - 2001-01-02T00:00:00.000000000+0000 "測試_Русский___ě_áñ👸🏼🧝🏾\u200d♀️💆🏿\u200d♂️🐨🤙🏼🤮🧑🏻\u200d🔧🧑\u200d🔬éééö/測試_Русский___ě_áñ👸🏼🧝🏾\u200d♀️💆🏿\u200d♂️🐨🤙🏼🤮🧑🏻\u200d🔧🧑\u200d🔬éééö.txt"

cmd/bisync/testdata/test_normalization/golden/test.log

@@ -36,16 +36,20 @@ INFO  : - Path2    File is new                        - f
 INFO  : - Path2    File is new                        - folder/hello,WORLD!.txt
 INFO  : Path2:    3 changes:    2 new,    1 newer,    0 older,    0 deleted
 INFO  : Applying changes
-INFO  : - Path1    Queue copy to Path2                - {path2/}folder/HeLlO,wOrLd!.txt
+INFO  : Checking potential conflicts...
-INFO  : - Path1    Queue copy to Path2                - {path2/}folder/éééö.txt
+NOTICE: Local file system at {path2}: 0 differences found
+NOTICE: Local file system at {path2}: 2 matching files
+INFO  : Finished checking the potential conflicts. %!s(<nil>)
+NOTICE: - WARNING  New or changed in both paths       - folder/HeLlO,wOrLd!.txt
+INFO  : folder/hello,WORLD!.txt: Files are equal but will copy anyway to fix case to folder/HeLlO,wOrLd!.txt
+NOTICE: - WARNING  New or changed in both paths       - folder/éééö.txt
+INFO  : folder/éééö.txt: Files are equal but will copy anyway to fix case to folder/éééö.txt
 INFO  : - Path1    Queue copy to Path2                - "{path2/}測試_Русский___ě_áñ👸🏼🧝🏾\u200d♀️💆🏿\u200d♂️🐨🤙🏼🤮🧑🏻\u200d🔧🧑\u200d🔬éééö/測試_Русский___ě_áñ👸🏼🧝🏾\u200d♀️💆🏿\u200d♂️🐨🤙🏼🤮🧑🏻\u200d🔧🧑\u200d🔬éééö.txt"
 INFO  : - Path2    Queue copy to Path1                - {path1/}file1.txt
-INFO  : - Path2    Queue copy to Path1                - {path1/}folder/éééö.txt
-INFO  : - Path2    Queue copy to Path1                - {path1/}folder/hello,WORLD!.txt
 INFO  : - Path2    Do queued copies to                - Path1
-INFO  : folder/HeLlO,wOrLd!.txt: Fixed case by renaming to: folder/hello,WORLD!.txt
-INFO  : folder/éééö.txt: Fixed case by renaming to: folder/éééö.txt
 INFO  : - Path1    Do queued copies to                - Path2
+INFO  : folder/hello,WORLD!.txt: Fixed case by renaming to: folder/HeLlO,wOrLd!.txt
+INFO  : folder/éééö.txt: Fixed case by renaming to: folder/éééö.txt
 INFO  : Updating listings
 INFO  : Validating listings for Path1 "{path1/}" vs Path2 "{path2/}"
 INFO  : Bisync successful
@@ -87,12 +91,16 @@ INFO  : - Path2    File is new                        - f
 INFO  : - Path2    File is new                        - folder/hello,WORLD!.txt
 INFO  : Path2:    3 changes:    2 new,    1 newer,    0 older,    0 deleted
 INFO  : Applying changes
-INFO  : - Path1    Queue copy to Path2                - {path2/}folder/HeLlO,wOrLd!.txt
+INFO  : Checking potential conflicts...
-INFO  : - Path1    Queue copy to Path2                - {path2/}folder/éééö.txt
+NOTICE: Local file system at {path2}: 0 differences found
+NOTICE: Local file system at {path2}: 2 matching files
+INFO  : Finished checking the potential conflicts. %!s(<nil>)
+NOTICE: - WARNING  New or changed in both paths       - folder/HeLlO,wOrLd!.txt
+INFO  : Files are equal! Skipping: folder/HeLlO,wOrLd!.txt
+NOTICE: - WARNING  New or changed in both paths       - folder/éééö.txt
+INFO  : Files are equal! Skipping: folder/éééö.txt
 INFO  : - Path1    Queue copy to Path2                - "{path2/}測試_Русский___ě_áñ👸🏼🧝🏾\u200d♀️💆🏿\u200d♂️🐨🤙🏼🤮🧑🏻\u200d🔧🧑\u200d🔬éééö/測試_Русский___ě_áñ👸🏼🧝🏾\u200d♀️💆🏿\u200d♂️🐨🤙🏼🤮🧑🏻\u200d🔧🧑\u200d🔬éééö.txt"
 INFO  : - Path2    Queue copy to Path1                - {path1/}file1.txt
-INFO  : - Path2    Queue copy to Path1                - {path1/}folder/éééö.txt
-INFO  : - Path2    Queue copy to Path1                - {path1/}folder/hello,WORLD!.txt
 INFO  : - Path2    Do queued copies to                - Path1
 INFO  : - Path1    Do queued copies to                - Path2
 INFO  : Updating listings
@@ -108,14 +116,12 @@ INFO  : - Path1    Resync is copying UNIQUE OR DIFFERING files to
 INFO  : Resync updating listings
 INFO  : Bisync successful
 
-(27)  : test changed on both paths
+(27)  : test changed on one path
 (28)  : touch-copy 2001-01-05 {datadir/}file1.txt {path2/}
 (29)  : copy-as-NFC {datadir/}file1.txt {path1/}測試_Русский___ě_áñ👸🏼🧝🏾‍♀️💆🏿‍♂️🐨🤙🏼🤮🧑🏻‍🔧🧑‍🔬éééö 測試_Русский___ě_áñ👸🏼🧝🏾‍♀️💆🏿‍♂️🐨🤙🏼🤮🧑🏻‍🔧🧑‍🔬éééö.txt
 (30)  : copy-as-NFC {datadir/}file1.txt {path1/}folder éééö.txt
 (31)  : copy-as-NFC {datadir/}file1.txt {path1/}folder HeLlO,wOrLd!.txt
-(32)  : copy-as-NFD {datadir/}file1.txt {path2/}folder éééö.txt
+(32)  : bisync norm
-(33)  : copy-as-NFD {datadir/}file1.txt {path2/}folder hello,WORLD!.txt
-(34)  : bisync norm
 INFO  : Synching Path1 "{path1/}" with Path2 "{path2/}"
 INFO  : Building Path1 and Path2 listings
 INFO  : Path1 checking for diffs
@@ -125,16 +131,12 @@ INFO  : - Path1    File is newer                      - "
 INFO  : Path1:    3 changes:    0 new,    3 newer,    0 older,    0 deleted
 INFO  : Path2 checking for diffs
 INFO  : - Path2    File is newer                      - file1.txt
-INFO  : - Path2    File is newer                      - folder/éééö.txt
+INFO  : Path2:    1 changes:    0 new,    1 newer,    0 older,    0 deleted
-INFO  : - Path2    File is newer                      - folder/hello,WORLD!.txt
-INFO  : Path2:    3 changes:    0 new,    3 newer,    0 older,    0 deleted
 INFO  : Applying changes
-INFO  : - Path1    Queue copy to Path2                - {path2/}folder/HeLlO,wOrLd!.txt
+INFO  : - Path1    Queue copy to Path2                - {path2/}folder/hello,WORLD!.txt
 INFO  : - Path1    Queue copy to Path2                - {path2/}folder/éééö.txt
 INFO  : - Path1    Queue copy to Path2                - "{path2/}測試_Русский___ě_áñ👸🏼🧝🏾\u200d♀️💆🏿\u200d♂️🐨🤙🏼🤮🧑🏻\u200d🔧🧑\u200d🔬éééö/測試_Русский___ě_áñ👸🏼🧝🏾\u200d♀️💆🏿\u200d♂️🐨🤙🏼🤮🧑🏻\u200d🔧🧑\u200d🔬éééö.txt"
 INFO  : - Path2    Queue copy to Path1                - {path1/}file1.txt
-INFO  : - Path2    Queue copy to Path1                - {path1/}folder/éééö.txt
-INFO  : - Path2    Queue copy to Path1                - {path1/}folder/hello,WORLD!.txt
 INFO  : - Path2    Do queued copies to                - Path1
 INFO  : - Path1    Do queued copies to                - Path2
 INFO  : Updating listings

cmd/bisync/testdata/test_normalization/scenario.txt

@@ -43,11 +43,9 @@ bisync norm force
 test resync
 bisync resync norm
 
-test changed on both paths
+test changed on one path
 touch-copy 2001-01-05 {datadir/}file1.txt {path2/}
 copy-as-NFC {datadir/}file1.txt {path1/}測試_Русский___ě_áñ👸🏼🧝🏾‍♀️💆🏿‍♂️🐨🤙🏼🤮🧑🏻‍🔧🧑‍🔬éééö 測試_Русский___ě_áñ👸🏼🧝🏾‍♀️💆🏿‍♂️🐨🤙🏼🤮🧑🏻‍🔧🧑‍🔬éééö.txt
 copy-as-NFC {datadir/}file1.txt {path1/}folder éééö.txt
 copy-as-NFC {datadir/}file1.txt {path1/}folder HeLlO,wOrLd!.txt
-copy-as-NFD {datadir/}file1.txt {path2/}folder éééö.txt
-copy-as-NFD {datadir/}file1.txt {path2/}folder hello,WORLD!.txt
 bisync norm

docs/content/bisync.md

@@ -591,17 +591,8 @@ instead of specifying them with command flags. (You can still override them as n
 
 ### Case (and unicode) sensitivity {#case-sensitivity}
 
-Synching with **case-insensitive** filesystems, such as Windows or `Box`,
+As of `v1.65`, case and unicode form differences no longer cause critical errors,
-can result in unusual behavior. As of `v1.65`, case and unicode form differences no longer cause critical errors,
+and normalization (when comparing between filesystems) is handled according to the same flags and defaults as `rclone sync`.
-however they may cause unexpected delta outcomes, due to the delta engine still being case-sensitive.
-This will be fixed in a future release. The near-term workaround is to make sure that files on both sides
-don't have spelling case differences (`Smile.jpg` vs. `smile.jpg`).
-
-The same limitation applies to Unicode normalization forms.
-This [particularly applies to macOS](https://github.com/rclone/rclone/issues/7270),
-which prefers NFD and sometimes auto-converts filenames from the NFC form used by most other platforms.
-This should no longer cause bisync to fail entirely, but may cause surprising delta results, as explained above.
-
 See the following options (all of which are supported by bisync) to control this behavior more granularly:
 - [`--fix-case`](/docs/#fix-case)
 - [`--ignore-case-sync`](/docs/#ignore-case-sync)
@@ -609,6 +600,10 @@ See the following options (all of which are supported by bisync) to control this
 - [`--local-unicode-normalization`](/local/#local-unicode-normalization) and
 [`--local-case-sensitive`](/local/#local-case-sensitive) (caution: these are normally not what you want.)
 
+Note that in the (probably rare) event that `--fix-case` is used AND a file is new/changed on both sides 
+AND the checksums match AND the filename case does not match, the Path1 filename is considered the winner, 
+for the purposes of `--fix-case` (Path2 will be renamed to match it).
+
 ## Windows support {#windows}
 
 Bisync has been tested on Windows 8.1, Windows 10 Pro 64-bit and on Windows
@@ -1292,7 +1287,7 @@ about _Unison_ and synchronization in general.
 * A few basic terminal colors are now supported, controllable with [`--color`](/docs/#color-when) (`AUTO`|`NEVER`|`ALWAYS`)
 * Initial listing snapshots of Path1 and Path2 are now generated concurrently, using the same "march" infrastructure as `check` and `sync`,
 for performance improvements and less [risk of error](https://forum.rclone.org/t/bisync-bugs-and-feature-requests/37636#:~:text=4.%20Listings%20should%20alternate%20between%20paths%20to%20minimize%20errors).
-* Better handling of unicode normalization and case insensitivity, support for [`--fix-case`](/docs/#fix-case), [`--ignore-case-sync`](/docs/#ignore-case-sync), [`--no-unicode-normalization`](/docs/#no-unicode-normalization)
+* Fixed handling of unicode normalization and case insensitivity, support for [`--fix-case`](/docs/#fix-case), [`--ignore-case-sync`](/docs/#ignore-case-sync), [`--no-unicode-normalization`](/docs/#no-unicode-normalization)
 * `--resync` is now much more efficient (especially for users of `--create-empty-src-dirs`)
 
 ### `v1.64`