docs: function clone(options) {
      assert.ok(options.repository, 'repository is mandatory');
  
      var branchOrTag = options.branch || options.tag;
      var args = [
        'clone',
        options.repository,
        options.directory,
        branchOrTag ? ('-b' + branchOrTag) : null,
        options.origin ? ('-o' + options.origin) : null,
        options.recursive ? '--recursive' : null,
        options.bare ? '--bare' : null,
        options.depth ? '--depth' : null,
        options.depth ? '' + options.depth : null
      ];
  
      return git(args)
          .then(silent);
    }