cache "Convenience accessor" in controllers create fragments that expire_fragment can't expire

Typical Disclaimer: Maybe I'm missing something, but this is not working/intuitive and causing problems. At best it's a doc issue?

The cache 'helper in controllers looks like so

# actionpack/lib/action_controller/caching.rb, line 76
def cache(key, options = {}, &block)
  if cache_configured?
    cache_store.fetch(ActiveSupport::Cache.expand_cache_key(key, :controller), options, &block)
  else
    yield
  end
end

Note that expand_cache_key is passed :controller, which namespaces the cache key.

If I want to explicitly expire this fragment, using (naturally) expire_fragment, it is impossible. This is because expire_fragment calls fragment_cache_key which explicitly sets the namespace to :views

def fragment_cache_key(key)
  ActiveSupport::Cache.expand_cache_key(key.is_a?(Hash) ? url_for(key).split("://").last : key, :views)
end

This leaves the developer having to create their own version of "expires_fragment" for controller namedspaced fragments. Or, in my case, I just overrode the controllers "cache" accessor so that it didn't namespace it with :controller, because frankly, it doesn't matter to me where the item is cached from.

I'm not familiar enough with how rails is organized to make a best practice call for how this can be resolved without ruffling feathers, but it seemed worth bringing up, as it's a head-scratching moment! Personally, the namespacing is something i don't like as a developer, but I imagine a patch that removes it would not be accepted.