anchor.diff:      ProfileDeps = rebar_state:get(State, {deps, default}, []),
       Deps = [Dep || Dep <- TopDeps ++ ProfileDeps, % TopDeps > ProfileDeps
                      is_atom(Dep) orelse is_atom(element(1, Dep))],
  -    Names = parse_names(rebar_utils:to_binary(proplists:get_value(package, Args, <<"">>)), Locks),
  -
  +    Names = case handle_args(State) of
  +        {false, undefined} -> throw(?PRV_ERROR(no_arg));
  +        {true, _} -> [Name || {Name, _, 0} <- Locks];
  +        {false, Packages} -> Bin = rebar_utils:to_binary(Packages),
  +            lists:usort(re:split(Bin, <<" *, *">>, [trim, unicode]))
  +        end,
       DepsDict = deps_dict(rebar_state:all_deps(State)),
       AltDeps = find_non_default_deps(Deps, State),
       FilteredNames = cull_default_names_if_profiles(Names, Deps, State),
  
positive.code:                                                    {desc, "Upgrade project dependencies. Mentioning no application "
                                                            "will upgrade all dependencies. To upgrade specific dependencies, "
                                                            "their names can be listed in the command."},
                                                     {opts, [
                                                            {package, undefined, undefined, string,
                                                             "List of packages to upgrade. If not specified, all dependencies are upgraded."}
                                                            ]}])),
      {ok, State1}.
  
  
negative.code: format_error({checkout_dependency, Name}) ->
      io_lib:format("Dependency ~ts is a checkout dependency under _checkouts/ and checkouts cannot be upgraded.",
                    [Name]);
  format_error(no_arg) -> 
      "Specify a list of dependencies to unlock, or --all to unlock them all";
  format_error(Reason) ->
      io_lib:format("~p", [Reason]).
  
  handle_args(State) -> 
      {Args, _} = rebar_state:command_parsed_args(State),
      All = proplists:get_value(all, Args, false),
      Package = proplists:get_value(package, Args),
      {All, Package}.
  
  %% fetch updates for package deps that have been unlocked for upgrade
  update_pkg_deps([], _, _) ->
  