refactor: Enhance rules tests.

- refactor: change incorrect package.
- refactor: test readability.

middlewares/replace_path.go

@@ -4,15 +4,15 @@ import (
 	"net/http"
 )
 
+// ReplacedPathHeader is the default header to set the old path to
+const ReplacedPathHeader = "X-Replaced-Path"
+
 // ReplacePath is a middleware used to replace the path of a URL request
 type ReplacePath struct {
 	Handler http.Handler
 	Path    string
 }
 
-// ReplacedPathHeader is the default header to set the old path to
-const ReplacedPathHeader = "X-Replaced-Path"
-
 func (s *ReplacePath) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	r.Header.Add(ReplacedPathHeader, r.URL.Path)
 	r.URL.Path = s.Path