lib: Return error from db.FileSet.Snapshot (fixes #7419, ref #5907) (#7424)

lib/model/folder_recvenc.go

@@ -32,10 +32,10 @@ func newReceiveEncryptedFolder(model *model, fset *db.FileSet, ignores *ignore.M
 }
 
 func (f *receiveEncryptedFolder) Revert() {
-	f.doInSync(func() error { f.revert(); return nil })
+	f.doInSync(f.revert)
 }
 
-func (f *receiveEncryptedFolder) revert() {
+func (f *receiveEncryptedFolder) revert() error {
 	l.Infof("Reverting unexpected items in folder %v (receive-encrypted)", f.Description())
 
 	f.setState(FolderScanning)
@@ -46,7 +46,10 @@ func (f *receiveEncryptedFolder) revert() {
 		return nil
 	})
 
-	snap := f.fset.Snapshot()
+	snap, err := f.dbSnapshot()
+	if err != nil {
+		return err
+	}
 	defer snap.Release()
 	var iterErr error
 	var dirs []string
@@ -85,12 +88,10 @@ func (f *receiveEncryptedFolder) revert() {
 
 	f.revertHandleDirs(dirs, snap)
 
-	if iterErr == nil {
-		iterErr = batch.flush()
-	}
 	if iterErr != nil {
-		l.Infoln("Failed to delete unexpected items:", iterErr)
+		return iterErr
 	}
+	return batch.flush()
 }
 
 func (f *receiveEncryptedFolder) revertHandleDirs(dirs []string, snap *db.Snapshot) {