From 3d81b75f441414a9ccea3b9413c09116fda4a51b Mon Sep 17 00:00:00 2001
From: ssaqua <ssaqua@users.noreply.github.com>
Date: Mon, 29 Oct 2018 17:05:45 +1300
Subject: [PATCH] dedupe: check for existing filename before renaming a dupe
 file

---
 fs/operations/dedupe.go      | 30 +++++++++++++++++++++++-------
 fs/operations/dedupe_test.go | 14 +++++++++++---
 2 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/fs/operations/dedupe.go b/fs/operations/dedupe.go
index a89b19a6a..8c6f5447f 100644
--- a/fs/operations/dedupe.go
+++ b/fs/operations/dedupe.go
@@ -18,16 +18,32 @@ import (
 )
 
 // dedupeRename renames the objs slice to different names
-func dedupeRename(remote string, objs []fs.Object) {
-	f := objs[0].Fs()
+func dedupeRename(f fs.Fs, remote string, objs []fs.Object) {
 	doMove := f.Features().Move
 	if doMove == nil {
 		log.Fatalf("Fs %v doesn't support Move", f)
 	}
 	ext := path.Ext(remote)
 	base := remote[:len(remote)-len(ext)]
+
+outer:
 	for i, o := range objs {
-		newName := fmt.Sprintf("%s-%d%s", base, i+1, ext)
+		suffix := 1
+		newName := fmt.Sprintf("%s-%d%s", base, i+suffix, ext)
+		_, err := f.NewObject(newName)
+		for ; err != fs.ErrorObjectNotFound; suffix++ {
+			if err != nil {
+				fs.CountError(err)
+				fs.Errorf(o, "Failed to check for existing object: %v", err)
+				continue outer
+			}
+			if suffix > 100 {
+				fs.Errorf(o, "Could not find an available new name")
+				continue outer
+			}
+			newName = fmt.Sprintf("%s-%d%s", base, i+suffix, ext)
+			_, err = f.NewObject(newName)
+		}
 		if !fs.Config.DryRun {
 			newObj, err := doMove(o, newName)
 			if err != nil {
@@ -81,7 +97,7 @@ func dedupeDeleteIdentical(ht hash.Type, remote string, objs []fs.Object) (remai
 }
 
 // dedupeInteractive interactively dedupes the slice of objects
-func dedupeInteractive(ht hash.Type, remote string, objs []fs.Object) {
+func dedupeInteractive(f fs.Fs, ht hash.Type, remote string, objs []fs.Object) {
 	fmt.Printf("%s: %d duplicates remain\n", remote, len(objs))
 	for i, o := range objs {
 		md5sum, err := o.Hash(ht)
@@ -96,7 +112,7 @@ func dedupeInteractive(ht hash.Type, remote string, objs []fs.Object) {
 		keep := config.ChooseNumber("Enter the number of the file to keep", 1, len(objs))
 		dedupeDeleteAllButOne(keep-1, remote, objs)
 	case 'r':
-		dedupeRename(remote, objs)
+		dedupeRename(f, remote, objs)
 	}
 }
 
@@ -276,7 +292,7 @@ func Deduplicate(f fs.Fs, mode DeduplicateMode) error {
 			}
 			switch mode {
 			case DeduplicateInteractive:
-				dedupeInteractive(ht, remote, objs)
+				dedupeInteractive(f, ht, remote, objs)
 			case DeduplicateFirst:
 				dedupeDeleteAllButOne(0, remote, objs)
 			case DeduplicateNewest:
@@ -286,7 +302,7 @@ func Deduplicate(f fs.Fs, mode DeduplicateMode) error {
 				sort.Sort(objectsSortedByModTime(objs)) // sort oldest first
 				dedupeDeleteAllButOne(0, remote, objs)
 			case DeduplicateRename:
-				dedupeRename(remote, objs)
+				dedupeRename(f, remote, objs)
 			case DeduplicateLargest:
 				largest, largestIndex := int64(-1), -1
 				for i, obj := range objs {
diff --git a/fs/operations/dedupe_test.go b/fs/operations/dedupe_test.go
index abf4b1426..bcb27f5dc 100644
--- a/fs/operations/dedupe_test.go
+++ b/fs/operations/dedupe_test.go
@@ -155,7 +155,8 @@ func TestDeduplicateRename(t *testing.T) {
 	file1 := r.WriteUncheckedObject("one.txt", "This is one", t1)
 	file2 := r.WriteUncheckedObject("one.txt", "This is one too", t2)
 	file3 := r.WriteUncheckedObject("one.txt", "This is another one", t3)
-	r.CheckWithDuplicates(t, file1, file2, file3)
+	file4 := r.WriteUncheckedObject("one-1.txt", "This is not a duplicate", t1)
+	r.CheckWithDuplicates(t, file1, file2, file3, file4)
 
 	err := operations.Deduplicate(r.Fremote, operations.DeduplicateRename)
 	require.NoError(t, err)
@@ -168,13 +169,20 @@ func TestDeduplicateRename(t *testing.T) {
 			remote := o.Remote()
 			if remote != "one-1.txt" &&
 				remote != "one-2.txt" &&
-				remote != "one-3.txt" {
+				remote != "one-3.txt" &&
+				remote != "one-4.txt" {
 				t.Errorf("Bad file name after rename %q", remote)
 			}
 			size := o.Size()
-			if size != file1.Size && size != file2.Size && size != file3.Size {
+			if size != file1.Size &&
+				size != file2.Size &&
+				size != file3.Size &&
+				size != file4.Size {
 				t.Errorf("Size not one of the object sizes %d", size)
 			}
+			if remote == "one-1.txt" && size != file4.Size {
+				t.Errorf("Existing non-duplicate file modified %q", remote)
+			}
 		})
 		return nil
 	}))