title: How can two branches be combined into a single branch based on the date of each commit?
body: <p>Let's say I have a git repository that looks like this:</p>
  
  <pre><code>merge-base---A1--A2------A3------A4 (branchA)
            \
             ----------B1------B2 (branchB)
  </code></pre>
  
  <p>To make things simpler, let's say the commits on branchA are strictly modifications to fileA, and the commits on branchB are strictly modifications to fileB.</p>
  
  <p>I want to combine these branches into a third branch, branchAB, where the commits will be ordered by date:</p>
  
  <pre><code>merge-base---A1--A2------A3------A4 (branchA)
            \
             ----------B1------B2 (branchB)
              \
               A1--A2--B1--A3--B2--A4 (branchAB)
  </code></pre>
  
  <p>Is there a way to automatically do this with a single git command, or am I stuck with manual methods (e.g. cherry picking or rebase -i)?</p>
  
  <p>BTW, <code>merge-base</code> is a tag.</p>