title: Disable Sprockets asset caching in development
body: <p>I'm using Rails 3.2.13 and the Rails Asset Pipeline.  I want to use the Asset Pipeline so I can use SASS and CoffeeScript and ERB for my assets and have the Pipeline automatically compile them, so I cannot turn off the pipeline in development. I am not precompiling assets in development ever and there is not even a <code>public/assets/</code> directory.</p>
  
  <p>However, when I make changes to an included file, such as to a <code>_partial.html.erb</code> file that is included (rendered) in a <code>layout.html.erb</code> file, without changing the file doing the including itself (in this example <code>layout.html.erb</code>), Sprockets doesn't detect the change and invalidate the cache, so I keep getting the same stale file.  When I'm doing this in active development, I want to disable any caching of assets so I can get the changes on every request but I cannot figure out how to do this. I have set all of the following in my <code>development.rb</code>:</p>
  
  <pre><code>config.action_controller.perform_caching = false
  config.action_dispatch.rack_cache =  nil
  config.middleware.delete Rack::Cache
  config.assets.debug = true
  config.assets.compress = false
  config.cache_classes = false
  </code></pre>
  
  <p>Still, even with this, files show up under <code>tmp/cache/assets/</code> and <code>tmp/cache/sass/</code> and changes are not available on future requests.  Right now I have to manually delete those directories every time I want to see a change.</p>
  
  <p>Unfortunately, the entire contents of the <a href="http://guides.rubyonrails.org/asset_pipeline.html">How Caching Works</a> section of the RoR Guide for the Asset Pipeline is:</p>
  
  <blockquote>
    <p>Sprockets uses the default Rails cache store to cache assets in
    development and production.</p>
    
    <p>TODO: Add more about changing the default store.</p>
  </blockquote>
  
  <p>So, how can I get Sprockets to compile assets on demand but not cache the results?</p>