Support Rails 6.1.3.2 & 6.0.3.7 and use symbols for polymorphic routes

[lostmahbles]

This potentially fixes #1971. I didn't do a thorough dive, but these changes got our admin back up and running. This also encompasses the changes in #1970.

[cgrothaus]

question: is this necessary?

I have the feeling that Resource as an inner class of Namespace is only ever initialized from there. At least I found now other places when grepping the codebase. And in Namespace, namespace is already made sure to be a symbol.

[nickcharlton]

Good catch! I removed this in the branch I'm trying to test and I think you're right.

[nickcharlton]

I've tested this on a thoughtbot project which uses Administrate fairly extensively, plus I'm trusting the now passing test suite to be capturing the original error before the symbol change successfully. I'm going to merge this once CI passes and then sort out a new release today.

If anyone's following along and having other issues relating to these Rails releases (both 6.1.3.2 and to 6.0.3.7) I'd love to hear about them!

[ELepolt]

Utilizing this commit I have the following two lines, and I am still getting this error. Any thoughts on which part is still upset?

- Administrate::Namespace.new(namespace).resources.each do |resource|
    = link_to(display_resource_name(resource), [namespace.to_sym, resource.path], class: "navigation__link navigation__link--#{nav_link_state(resource)}")

[cgrothaus]

I think resource.path is a String, and that is causing the error in Rails routing. It must be a Symbol instead, try resource.path.to_sym. Also, I think that namespace is already a Symbol, thanks to the fix, so you can omit .to_sym there.

[kemenaran]

You may need to update your _navigation.html.erb file according to the latest template from administrate :

  <%= link_to(
      display_resource_name(resource),
-      [namespace, resource.path],
+      resource_index_route(resource),
      class: "navigation__link navigation__link--#{nav_link_state(resource)}"
    ) %>