lib/model: Fix checking children when trying to delete a dir (fixes #6646) (#6647)

lib/model/folder_sendrecv.go

@@ -64,8 +64,9 @@ var (
 	activity                    = newDeviceActivity()
 	errNoDevice                 = errors.New("peers who had this file went away, or the file has changed while syncing. will retry later")
 	errDirPrefix                = "directory has been deleted on a remote device but "
-	errDirHasToBeScanned      = errors.New(errDirPrefix + "contains unexpected files, scheduling scan")
+	errDirHasToBeScanned        = errors.New(errDirPrefix + "contains changed files, scheduling scan")
 	errDirHasIgnored            = errors.New(errDirPrefix + "contains ignored files (see ignore documentation for (?d) prefix)")
+	errDirHasReceiveOnlyChanged = errors.New(errDirPrefix + "contains locally changed files")
 	errDirNotEmpty              = errors.New(errDirPrefix + "is not empty; the contents are probably ignored on that remote device, but not locally")
 	errNotAvailable             = errors.New("no connected device has the required version of this file")
 	errModified                 = errors.New("file modified but not rescanned; will try again later")
@@ -1819,32 +1820,53 @@ func (f *sendReceiveFolder) deleteDirOnDisk(dir string, snap *db.Snapshot, scanC
 
 	toBeDeleted := make([]string, 0, len(files))
 
-	hasIgnored := false
-	hasKnown := false
-	hasToBeScanned := false
+	var hasIgnored, hasKnown, hasToBeScanned, hasReceiveOnlyChanged bool
 
 	for _, dirFile := range files {
 		fullDirFile := filepath.Join(dir, dirFile)
-		if fs.IsTemporary(dirFile) || f.ignores.Match(fullDirFile).IsDeletable() {
+		switch {
+		case fs.IsTemporary(dirFile) || f.ignores.Match(fullDirFile).IsDeletable():
 			toBeDeleted = append(toBeDeleted, fullDirFile)
-		} else if f.ignores != nil && f.ignores.Match(fullDirFile).IsIgnored() {
+			continue
+		case f.ignores != nil && f.ignores.Match(fullDirFile).IsIgnored():
 			hasIgnored = true
-		} else if cf, ok := snap.Get(protocol.LocalDeviceID, fullDirFile); !ok || cf.IsDeleted() || cf.IsInvalid() {
-			// Something appeared in the dir that we either are not aware of
-			// at all, that we think should be deleted or that is invalid,
-			// but not currently ignored -> schedule scan. The scanChan
-			// might be nil, in which case we trust the scanning to be
-			// handled later as a result of our error return.
-			if scanChan != nil {
-				scanChan <- fullDirFile
+			continue
 		}
+		cf, ok := snap.Get(protocol.LocalDeviceID, fullDirFile)
+		switch {
+		case !ok || cf.IsDeleted():
+			// Something appeared in the dir that we either are not
+			// aware of at all or that we think should be deleted
+			// -> schedule scan.
+			scanChan <- fullDirFile
 			hasToBeScanned = true
-		} else {
+			continue
+		case ok && f.Type == config.FolderTypeReceiveOnly && cf.IsReceiveOnlyChanged():
+			hasReceiveOnlyChanged = true
+			continue
+		}
+		info, err := f.fs.Lstat(fullDirFile)
+		var diskFile protocol.FileInfo
+		if err == nil {
+			diskFile, err = scanner.CreateFileInfo(info, fullDirFile, f.fs)
+		}
+		if err != nil {
+			// Lets just assume the file has changed.
+			scanChan <- fullDirFile
+			hasToBeScanned = true
+			continue
+		}
+		if !cf.IsEquivalentOptional(diskFile, f.ModTimeWindow(), f.IgnorePerms, true, protocol.LocalAllFlags) {
+			// File on disk changed compared to what we have in db
+			// -> schedule scan.
+			scanChan <- fullDirFile
+			hasToBeScanned = true
+			continue
+		}
 		// Dir contains file that is valid according to db and
 		// not ignored -> something weird is going on
 		hasKnown = true
 	}
-	}
 
 	if hasToBeScanned {
 		return errDirHasToBeScanned
@@ -1852,6 +1874,9 @@ func (f *sendReceiveFolder) deleteDirOnDisk(dir string, snap *db.Snapshot, scanC
 	if hasIgnored {
 		return errDirHasIgnored
 	}
+	if hasReceiveOnlyChanged {
+		return errDirHasReceiveOnlyChanged
+	}
 	if hasKnown {
 		return errDirNotEmpty
 	}

lib/model/folder_sendrecv_test.go

@@ -818,9 +818,14 @@ func TestCopyOwner(t *testing.T) {
 	// owner/group.
 
 	dbUpdateChan := make(chan dbUpdateJob, 1)
+	scanChan := make(chan string)
 	defer close(dbUpdateChan)
-	f.handleDir(dir, f.fset.Snapshot(), dbUpdateChan, nil)
-	<-dbUpdateChan // empty the channel for later
+	f.handleDir(dir, f.fset.Snapshot(), dbUpdateChan, scanChan)
+	select {
+	case <-dbUpdateChan: // empty the channel for later
+	case toScan := <-scanChan:
+		t.Fatal("Unexpected receive on scanChan:", toScan)
+	}
 
 	info, err := f.fs.Lstat("foo/bar")
 	if err != nil {
@@ -874,8 +879,12 @@ func TestCopyOwner(t *testing.T) {
 		SymlinkTarget: "over the rainbow",
 	}
 
-	f.handleSymlink(symlink, snap, dbUpdateChan, nil)
-	<-dbUpdateChan
+	f.handleSymlink(symlink, snap, dbUpdateChan, scanChan)
+	select {
+	case <-dbUpdateChan:
+	case toScan := <-scanChan:
+		t.Fatal("Unexpected receive on scanChan:", toScan)
+	}
 
 	info, err = f.fs.Lstat("foo/bar/sym")
 	if err != nil {