title: Ruby / Git library. How to get a full file of a particular check in?
body: <p>Am working on a script based on git repository. Using ruby's git library. </p>
  
  <p>Having trouble to find the feature to load the full file of a history check in. In git the content can be shown like:</p>
  
  <pre><code>git show 234h23h4j23l4j:path/to/file.java
  </code></pre>
  
  <p>Just need to know in ruby / git, how do I do that?</p>
  
  <p>Note that this commit (234h23h4j23l4j) does not necessarily have the file I'm looking at.</p>
  
  <p>Or if you know any other git library can easily do this please also recommend. We can still switch, it's not too late.</p>