title: Symfony2 Assetic Don't Generate Composite File on --env=dev
body: <p>Is there any way to tell the Assetic command-line file to not generate the composite "output" file when it builds for the dev environment?</p>
  
  <p>We have it running with the --watch configuration. We have composite files which take a long time to generate and aren't used, so it's a serious waste of time. It also causes it to regenerate all files in that stack, instead of the one single one that changes.</p>
  
  <p>Any ideas? If there isn't, I'm half-tempted to override the asset:dump command myself because we're seriously wasting 1-3 minutes every time we make a tiny file change. =(</p>
  
  <hr>
  
  <p>Symfony version: 2.2.0 (according to debug bar, just ran Composer update with no changes)</p>
  
  <p>config.yml (assetic block)</p>
  
  <pre><code>assetic:
    debug:          %kernel.debug%
    use_controller: false
    #bundles: []
    #java: /usr/bin/java
    filters:
      cssrewrite: ~
      less:
        node: /usr/bin/node
        node_paths: [/usr/local/lib/node_modules,/usr/lib/node_modules]
        apply_to: "\.less"
      typescript:
        resource: %kernel.root_dir%/../src/GamePlan/Bundle/CoreBundle/Resources/config/assetic.typescript.xml
        apply_to: "\.ts"
        tsc: /usr/local/bin/tsc
        node: /usr/bin/node
        useOut: false
  </code></pre>
  
  <p>(Custom TypeScriptFilter, but it is happening to CSS files as well, so it shouldn't be that which is causing it... it's also a relatively minor tweak to the one in the official repo.)</p>
  
  <p>config_dev.yml (assetic block)</p>
  
  <pre><code>assetic:
    use_controller: false
  </code></pre>
  
  <p>Example usage:</p>
  
  <pre><code>{% stylesheets output="bundles/mybundle/styles/mystyle.css"
      filter="cssrewrite"
      "@MyBundle/Resources/styles/a.less"
      "@MyBundle/Resources/styles/b.less"
      "@MyBundle/Resources/styles/subfolder/*.less"
      "@MyBundle/Resources/styles/subfolder/*/*.less"
  %}
  &lt;link type="text/css" rel="stylesheet" href="{{ asset_url }}"/&gt;
  {% endstylesheets %}
  </code></pre>
  
  <p>Running command (from /var/www as www-data):</p>
  
  <pre><code>php Symfony/app/console assetic:dump --env=dev [--watch]
  </code></pre>
  
  <p>With or without --watch doesn't change what files are generated, just if it does them all or just watches.</p>
  
  <p>Note sure if this will give anyone a clue as to what is going on, but it tries to generate the composite file before it generates the individual dev ones.</p>
  
  <p>I've also ensured I'm not duplicating any includes, referencing any composite files in other blocks, etc.</p>
  
  <p>It isn't loading the composite files in the HTML, but I can see them generated from the command.</p>
  
  <p>If any more info is needed, please let me know. Thanks.</p>