sync: add filter-sensitivity to --backup-dir option

The old Overlapping function and corresponding tests have been removed, as it has been completely replaced by the OverlappingFilterCheck function.

fs/operations/operations.go

@@ -815,17 +815,6 @@ func fixRoot(f fs.Info) string {
 	return s
 }
 
-// Overlapping returns true if fdst and fsrc point to the same
-// underlying Fs and they overlap.
-func Overlapping(fdst, fsrc fs.Info) bool {
-	if !SameConfig(fdst, fsrc) {
-		return false
-	}
-	fdstRoot := fixRoot(fdst)
-	fsrcRoot := fixRoot(fsrc)
-	return strings.HasPrefix(fdstRoot, fsrcRoot) || strings.HasPrefix(fsrcRoot, fdstRoot)
-}
-
 // OverlappingFilterCheck returns true if fdst and fsrc point to the same
 // underlying Fs and they overlap without fdst being excluded by any filter rule.
 func OverlappingFilterCheck(ctx context.Context, fdst fs.Fs, fsrc fs.Fs) bool {
@@ -1849,10 +1838,10 @@ func BackupDir(ctx context.Context, fdst fs.Fs, fsrc fs.Fs, srcFileName string)
 			return nil, fserrors.FatalError(errors.New("parameter to --backup-dir has to be on the same remote as destination"))
 		}
 		if srcFileName == "" {
-			if Overlapping(fdst, backupDir) {
+			if OverlappingFilterCheck(ctx, backupDir, fdst) {
 				return nil, fserrors.FatalError(errors.New("destination and parameter to --backup-dir mustn't overlap"))
 			}
-			if Overlapping(fsrc, backupDir) {
+			if OverlappingFilterCheck(ctx, backupDir, fsrc) {
 				return nil, fserrors.FatalError(errors.New("source and parameter to --backup-dir mustn't overlap"))
 			}
 		} else {

fs/operations/operations_test.go

@@ -1243,35 +1243,6 @@ func TestSame(t *testing.T) {
 	}
 }
 
-func TestOverlapping(t *testing.T) {
-	a := &testFsInfo{name: "name", root: "root"}
-	slash := string(os.PathSeparator) // native path separator
-	for _, test := range []struct {
-		name     string
-		root     string
-		expected bool
-	}{
-		{"name", "root", true},
-		{"namey", "root", false},
-		{"name", "rooty", false},
-		{"namey", "rooty", false},
-		{"name", "roo", false},
-		{"name", "root/toot", true},
-		{"name", "root/toot/", true},
-		{"name", "root" + slash + "toot", true},
-		{"name", "root" + slash + "toot" + slash, true},
-		{"name", "", true},
-		{"name", "/", true},
-	} {
-		b := &testFsInfo{name: test.name, root: test.root}
-		what := fmt.Sprintf("(%q,%q) vs (%q,%q)", a.name, a.root, b.name, b.root)
-		actual := operations.Overlapping(a, b)
-		assert.Equal(t, test.expected, actual, what)
-		actual = operations.Overlapping(b, a)
-		assert.Equal(t, test.expected, actual, what)
-	}
-}
-
 // testFs is for unit testing fs.Fs
 type testFs struct {
 	testFsInfo