title: Add existing directory as branch to git with worktree
body: <p>I have a simple repository and I need to have a branch checked out in a different directory. For that I use <code>git worktree</code>. Normally <code>git worktree add -B hello ../hello master</code> creates a new branch called <code>hello</code> from <code>master</code> and checks it out under <code>../hello</code>.</p>
  
  <p>That is actually exactly what I am looking for, except for that the directory already exists. <a href="https://www.git-scm.com/docs/git-worktree/2.5.1#git-worktree--Bltnew-branchgt" rel="nofollow noreferrer">According to the documentation</a> <code>-B</code> is supposed to ignore that and just use the files that are in the directory, but it still complains with:</p>
  
  <pre><code>$ git worktree add -B hello ../hello master
  Preparing worktree (resetting branch 'hello'; was at 0465e02)
  fatal: '../hello' already exists
  </code></pre>
  
  <p>Why does the command I use not work? See quote from the docs below. Do I misinterpret the docs?</p>
  
  <p>Quote from the documentation:</p>
  
  <blockquote>
    <p>By default, <strong>-b</strong> refuses to create a new branch if it already exists. <strong>-B</strong> overrides this safeguard, resetting <strong>&lt; new-branch ></strong> to <strong>&lt; branch ></strong></p>
  </blockquote>