fix annotate.go single resource check

pkg/kubectl/cmd/annotate.go

@@ -188,16 +188,7 @@ func (o *AnnotateOptions) Complete(f *cmdutil.Factory, out io.Writer, cmd *cobra
 
 // Validate checks to the AnnotateOptions to see if there is sufficient information run the command.
 func (o AnnotateOptions) Validate(args []string) error {
-	if err := validateAnnotations(o.removeAnnotations, o.newAnnotations); err != nil {
-		return err
-	}
-
-	// only apply resource version locking on a single resource
-	if len(o.resources) > 1 && len(o.resourceVersion) > 0 {
-		return fmt.Errorf("--resource-version may only be used with a single resource")
-	}
-
-	return nil
+	return validateAnnotations(o.removeAnnotations, o.newAnnotations)
 }
 
 // RunAnnotate does the work
@@ -207,6 +198,17 @@ func (o AnnotateOptions) RunAnnotate() error {
 		return err
 	}
 
+	var singularResource bool
+	r.IntoSingular(&singularResource)
+
+	// only apply resource version locking on a single resource.
+	// we must perform this check after o.builder.Do() as
+	// []o.resources can not not accurately return the proper number
+	// of resources when they are not passed in "resource/name" format.
+	if !singularResource && len(o.resourceVersion) > 0 {
+		return fmt.Errorf("--resource-version may only be used with a single resource")
+	}
+
 	return r.Visit(func(info *resource.Info, err error) error {
 		if err != nil {
 			return err