Conditional callback for asynchronous file copy

I'm trying to figure out the most elegant solution to do the following asynchronously using JavaScript (specifically node):

• Given a destination file name, check if it is a directory
• If it is a directory, delete it
• Copy a source file onto the destination file name

I would like to do this asynchronously using callbacks.

Here is what I have come up with:

  var preCopyOp = fs.lstatSync(dstFilename).isDirectory() ?
    function(callback) {
      rimraf(dstFilename, callback)
    } :
    function(callback) {
      callback();
    };

  preCopyOp(function() {
    ncp(srcFilename, dstFilename, function(err) {
      if(err) {
        return console.error(err);
      }
    });  
  });

The no-op passthrough function seems like a bit of a kludge to me. Is there a more elegant way to do this?