Create fake http.ResponseWriter for using in tests.

Example: sess, err := helpers.SessionStart(w, r) if err != nil && !errors.Is(err, os.ErrNotExist) { helpers.RespondAsBadRequest(w, r, err) return } defer sess.Close().

Example: if err = r.ParseForm(); err != nil { helpers.RespondAsBadRequest(w, r, err) return } if err = helpers.SetLanguageCookie(w, r); err != nil { helpers.RespondAsBadRequest(w, r, err) return }.

For funcs which write some data to http.ResponseWriter Example: w = NewFakeResponseWriter() w.Body, w.Headers, w.StatusCode.