title: How to update a single library with Composer?
body: <p>I need to install only 1 package for my SF2 distribution (DoctrineFixtures).</p>
  
  <p>When I run </p>
  
  <pre><code>php composer.phar update
  </code></pre>
  
  <p>I get</p>
  
  <pre><code>  - Updating twig/twig (dev-master 39d94fa =&gt; v1.13.0)
      The package has modified files:
      M CHANGELOG
      M doc/filters/batch.test
      M doc/filters/index.rst
      M doc/filters/url_encode.rst
      M doc/functions/index.rst
      M doc/tags/index.rst
      M doc/tests/index.rst
      M lib/Twig/Autoloader.php
      M lib/Twig/Compiler.php
      M lib/Twig/CompilerInterface.php
  -10 more files modified, choose "v" to view the full list
  </code></pre>
  
  <p>It appears the last developer edited a lot of files inside vendor.</p>
  
  <p>In order to get around this, I tried </p>
  
  <pre><code>php composer.phar update &lt;package_name&gt;
  </code></pre>
  
  <p>But that doesn't seem to work. How can I update/install only one library from composer.json?</p>