javascript_expansions and stylesheet_expansions seemingly ignored in Rails 3.1

I have been working with Rail 3.1 and just noticed when I turn on the asset pipeline, the javascript_expansions and stylesheet_expansions seem to be 开发者_Python百科ignored. Is this the correct behavior or might I be doing something wrong? I have done many google searches and come up with nothing on the matter.

After digging a bit deeper, I found that javascript_expansions and stylesheet_expansions are ignored in rails 3.1 if the asset pipeline is turned in favor of manifest files.