How to prevent rails from changing the path when the edit action is rendered from update action -

as far i'm aware standard rails pattern editing , updating resource.

i have route edit action on /users/:id/edit , both put , patch route update action on /users/:id.

here controller actions:

def edit   @user = user.find params[:id] end  def update   @user = user.find params[:id]    if @user.update_attributes(user_params)     redirect_to @user, success: "changes saved"   else     flash.now.alert = "unable change account details"     render :edit   end end 

and i'm using default form_for in form partial:

<%= form_for @user |f| %> 

which creating following form in html:

<form accept-charset="utf-8" action="/users/1" id="edit_user_1" method="post">   ...   <input name="_method" type="hidden" value="patch"> 

when call update_attributes succeeds user being redirected correctly, when call fails (due activerecord validations) render action displays edit view correctly, path in user's browser changes /users/1/edit /users/1.

from i've read appears expected behaviour of rails, seems confusing me thought core idea behind rest url referred canonical view of resource?

if redirect_to edit action instead of render url should be, lose error messages on form.

is there more sensible way persist url , error messages dumping errors session before using redirect_to? i'd avoid if can.

update:

the reason want url persist (as errors) because i'm using current_page? set active states in navigation. therefore 'edit' action in menu loses it's highlighting if form submitted errors.

the reason in /users/1 view rendered #update, not #edit.

by default resource path of #update same #show, different request method get , put. so, when #update renders html response, it's same #show.

i think result acceptable, no matter path in result expected. found, if using redirect, @user instance changed branch new 1 losing errors , previous fillings.

there workaround on path such using session pass instance variable, don't think worth effort. current result enough.

add

manipulating active states easy. don't current_page? needs code. use controller_path , action_name instead.

  if controller_path == 'users' && (action_name == 'edit' || 'update')       # add active class   end