Hard dependency on Sprockets prevents migration to Propshaft

• What were you trying to do?

I am following the Propshaft upgrade guide. After replacing Sprockets with Propshaft in my Gemfile, I expect Sprockets-related errors to disappear and Administrate views to render correctly.

• What did you end up with (logs, or, even better, example apps are great!)?

Sprockets is still invoked as it's a transitive gem dependency of Administrate, leading to Sprockets::Railtie::ManifestNeededError: Expected to find a manifest file in app/assets/config/manifest.js. As a workaround, an empty app/assets/config/manifest.js file can be kept.

However then, I get the error Propshaft::MissingAssetError: The asset 'administrate/application.css' was not found in the load path which appears to come from app/views/administrate/application/stylesheet.html.erb.

It looks like propshaft and sprockets do not play along each other nicely, and Administrate should support working with Propshaft, otherwise it prevents applications from migrating.

• What versions are you running?
  • Rails 7.0.2.2
  • administrate 0.17.0 rev 3b2413ac