update micro

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

file.go

@@ -13,7 +13,6 @@ import (
 
 var (
 	DefaultStructTag = "file"
-	ErrInvalidStruct = errors.New("invalid struct specified")
 	ErrPathNotExist  = errors.New("path is not exist")
 )
 
@@ -39,6 +38,10 @@ func (c *fileConfig) Init(opts ...config.Option) error {
 		}
 	}
 
+	if path == "" {
+		return ErrPathNotExist
+	}
+
 	c.path = path
 
 	return nil