fix file validator not work (#25)

fix file validator not work

Author: inhere

src/ValidationTrait.php

@@ -332,7 +332,8 @@ protected function fieldValidate(string $field, $value, string $validator, array
 
             // File resource check
         } elseif (self::isCheckFile($validator)) {
-            $passed = $this->$validator($field, ...array_values($args));
+            $method = "{$validator}Validator";
+            $passed = $this->$method($field, ...array_values($args));
 
             // other required* methods
         } elseif (method_exists($this, $validator)) {