title: Zsh tab completion duplicating command name
body: <p>I'm on OS X Mountain Lion, running the included ZSH shell (4.3.11) with Oh-My-ZSH installed over the top.</p>
  
  <p>When using tab completion with commands such as homebrew, when ZSH lists the available commands, it is also duplicating the command. For example:</p>
  
  <pre><code>$ brew {tab}
  </code></pre>
  
  <p>will result in:</p>
  
  <pre><code>$ brew brew 
  [list of homebrew commands]
  </code></pre>
  
  <p>I'm unsure what is causing this error, as when I resize the terminal window, the first instance of the command name disappears.</p>
  
  <p>If I hit backspace when the duplicates are displayed, I can only delete the second instance of the command, zsh won't let me backspace any further. Also, if I do remove the duplicate with backspace, zsh then acts as if there is no command typed at all.</p>
  
  <p>My .zshrc along with all my other .configuration files can be found at <a href="https://github.com/daviesjamie/dotfiles" rel="noreferrer">https://github.com/daviesjamie/dotfiles</a></p>
  
  <p><strong>UPDATE:</strong> I found <a href="https://stackoverflow.com/questions/11146306/">this post</a> about someone having the same problem on Ubuntu. However, I don't understand the given solution, and I'm not even sure if it applies to my set up?</p>