2 files changed, 22 insertions, 0 deletions
diff --git a/drive/sync.go b/drive/sync.go
index 204e7c2..2124f8f 100644
--- a/drive/sync.go
+++ b/drive/sync.go
@@ -73,6 +73,16 @@ func (self *Drive) prepareSyncFiles(localPath string, root *drive.File, cmp File
     }, nil
 }
 
+func (self *Drive) isSyncFile(id string) (bool, error) {
+    f, err := self.service.Files.Get(id).Fields("appProperties").Do()
+    if err != nil {
+        return false, fmt.Errorf("Failed to get file: %s", err)
+    }
+
+    _, ok := f.AppProperties["sync"]
+    return ok, nil
+}
+
 func prepareLocalFiles(root string) ([]*LocalFile, error) {
     var files []*LocalFile
 
diff --git a/drive/upload.go b/drive/upload.go
index 2b8c7c3..0bbc014 100644
--- a/drive/upload.go
+++ b/drive/upload.go
@@ -29,6 +29,18 @@ func (self *Drive) Upload(args UploadArgs) error {
         return fmt.Errorf("Chunk size is to big, max chunk size for this computer is %d", intMax() - 1)
     }
 
+    // Ensure that none of the parents are sync dirs
+    for _, parent := range args.Parents {
+        isSyncDir, err := self.isSyncFile(parent)
+        if err != nil {
+            return err
+        }
+
+        if isSyncDir {
+            return fmt.Errorf("%s is a sync directory, use 'sync upload' instead", parent)
+        }
+    }
+
     if args.Recursive {
         return self.uploadRecursive(args)
     }