title: How do I check git log for a "fast-forward" merge?
body: <p>In the following example, is there a way to know a merge happened?  Looking at git log, I can't tell I merged.</p>
  
  <pre><code># setup example directory
  $ mkdir test
  $ cd test
  $ git init
  $ touch a
  $ git add a
  $ git commit -m "1"
  
  # switch to different branch
  $ git checkout -b topic
  $ touch b
  $ git add b
  $ git commit -m "2"
  
  # go back to master and merge
  $ git checkout master
  $ git merge topic
  
  # git log
  
  commit cccc64de3947828f487a8ce3c3e72b0f68dc88c3
  Author: none
  Date:   Fri May 20 05:54:45 2011 -0700
  
      2
  
  commit a5d57454295759609d91a60219002e74016eed2b
  Author: none
  Date:   Fri May 20 05:54:29 2011 -0700
  
      1
  </code></pre>