title: Eclipse p2 director application cannot update a feature
body: <p>I am developing <a href="https://github.com/Nodeclipse/nodeclipse-1/tree/master/org.nodeclipse.ui/templates" rel="nofollow">Node.js script to install Eclipse plugins</a> by using <a href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.platform.doc.isv%2Freference%2Fmisc%2Fruntime-options.html" rel="nofollow">Eclipse built-in p2 director application</a>. And p2-director fails to update features in some cases.</p>
  
  <pre><code>D:\Workspaces\Nodeclipse-DEV\nodeclipse-1\org.nodeclipse.ui\templates&gt;node nodeclipse-install.js install -repository jar:file:/D:/Workspaces/Nodeclipse-DEV/nodeclipse-1/org.nodeclipse.site/target/org.nodeclipse.site-0.10.0-SNAPSHOT.zip!/ maven
  Nodeclipse CLI Installer (Eclipse Plugin Manager epm)
  starting eclipsec -nosplash -application org.eclipse.equinox.p2.director -repository jar:file:/D:/Workspaces/Nodeclipse-DEV/nodeclipse-1/org.nodeclipse.site/target/org.nodeclipse.site-0.10.0-SNAPSHOT.zip!/ -installIU org.nodeclipse.enide.maven.feature.feature.group -tag org.nodeclipse.enide.maven.feature.feature.group -vmargs -Declipse.p2.mirrors=false
  Installing org.nodeclipse.enide.maven.feature.feature.group 0.10.0.201402180840.
  
  Installation failed.
  
  Cannot complete the install because of a conflicting dependency.
   Software being installed: Enide Maven 0.10.0.201402180840 (org.nodeclipse.enide.maven.feature.feature.group 0.10.0.201402180840)
   Software currently installed: Enide Maven 0.10.0.201402170319 (org.nodeclipse.enide.maven.feature.feature.group 0.10.0.201402170319)
   Only one of the following can be installed at once:
    Enide Maven 0.10.0.201402180840 (org.nodeclipse.enide.maven.feature.feature.jar 0.10.0.201402180840)
    Enide Maven 0.10.0.201402170319 (org.nodeclipse.enide.maven.feature.feature.jar 0.10.0.201402170319)
   Cannot satisfy dependency:
    From: Enide Maven 0.10.0.201402170319 (org.nodeclipse.enide.maven.feature.feature.group 0.10.0.201402170319)
    To: org.nodeclipse.enide.maven.feature.feature.jar [0.10.0.201402170319]
   Cannot satisfy dependency:
    From: Enide Maven 0.10.0.201402180840 (org.nodeclipse.enide.maven.feature.feature.group 0.10.0.201402180840)
    To: org.nodeclipse.enide.maven.feature.feature.jar [0.10.0.201402180840]
  Application failed, log file location: E:\Eclipse\Enide-Studio-2014-try2-win64\eclipse\configuration\1392717353881.log
  
  eclipsec process exit code 13
  </code></pre>
  
  <p>I also tried passing both <code>.feature.jar</code> and <code>feature.group</code>.</p>
  
  <pre><code>eclipsec -nosplash -application org.eclipse.equinox.p2.director -repository jar:file:/D:/Workspaces/Nodeclipse-DEV/nodeclipse-1/org.nodeclipse.site/target/org.nodeclipse.site-0.10.0-SNAPSHOT.zip!/ -installIU org.nodeclipse.enide.maven.feature.feature.group -tag org.nodeclipse.enide.maven.feature.feature.group -vmargs -Declipse.p2.mirrors=false
  </code></pre>
  
  <p>This maybe related to the fact that <code>.maven</code> feature includes <code>.maven</code> and <code>.common</code> plugins. <code>.common</code> plugin is also used by other features.<br>
  However this also happens with other features, that have no shared dependencies. p2 director help page does not specify the logic nor gives references.</p>