500 error - #valid_action? called with the wrong arguments when rendering Field::HasMany

Created by: maxkwallace

This issue applies to the current, unreleased master branch, not to 0.4.0. And first off-- thanks for the awesome gem! Administrate has been a huge boon to my org, and I really appreciate all the hard work.

If I have two Resources with routes like:

resources :users
resources :orders, except: [:edit, :update]

And UserDashboard has orders: Field::HasMany, under SHOW_PAGE_ATTRIBUTES, when someone navigates to admin/users/:id (the show action) Administrate will render, among other things, administrate/app/views/fields/has_many/_show.html.erb, which looks like:

<% if field.resources.any? %>
  <%= render(
    "collection",
    collection_presenter: field.associated_collection,
    resources: field.resources(params[field.name])
  ) %>
  ...

Inside the collection partial, we have:

        <% if valid_action? :edit %>
          <td><%= link_to(
            t("administrate.actions.edit"),
            [:edit, namespace, resource],
            class: "action-edit",
          ) %></td>
        <% end %>

When we call valid_action? here, it looks up resource_name on the rendering Controller's resource_resolver, which is for the User Resource, not the Order Resource.

Since the Order Resource doesn't have an edit route declared in routes.rb, a 500 error gets thrown because the path link_to goes to look up doesn't exist.

The same issue exists for the other routes, not just :edit and :update.

---

Stop-gap solution (for anyone else running into this issue):

Put the following in your routes.rb, after your Administrate route declarations:

    get 'orders/:id/edit', to: 'orders#show', as: :edit_admin_order

This deals with the 500s, but the "Edit" links still get generated in collection partials.

---

Actual solution:

I spent about an hour unsuccessfully trying to come up with a fix for this in a PR. It's easy to write a heuristic to pass resource_name into valid_action? for the Resource being rendered, but I'm very unsure what would be required to make that correct in all cases, or if there's a larger refactor that would be more appropriate. Administrate::ResourceResolver defines a clear mapping from the URL path to the Resource, but I'm not sure about going the other way without breaking things in some cases.