%
% This file is part of AtomVM.
%
% Copyright 2023 Winford (Uncle Grumpy) <winford@object.stream>
%
% Licensed under the Apache License, Version 2.0 (the "License");
% you may not use this file except in compliance with the License.
% You may obtain a copy of the License at
%
%    http://www.apache.org/licenses/LICENSE-2.0
%
% Unless required by applicable law or agreed to in writing, software
% distributed under the License is distributed on an "AS IS" BASIS,
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
% See the License for the specific language governing permissions and
% limitations under the License.
%
% SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later
%

-module(whereis_dead_process).

-export([start/0]).

start() ->
    ok = test_one_name(),
    ok = test_two_names(),
    0.

test_one_name() ->
    test_names([foo]).

test_two_names() ->
    test_names([foo, bar]).

test_names(Names) ->
    {Pid, Monitor} = spawn_opt(fun() -> do_register(Names) end, [monitor]),
    ok =
        receive
            {'DOWN', Monitor, process, Pid, _} -> ok
        after 1000 -> timeout
        end,
    ok = test_unregistered(Names).

test_unregistered([]) ->
    ok;
test_unregistered([Name | T]) ->
    undefined = whereis(Name),
    test_unregistered(T).

do_register([]) ->
    ok;
do_register([Name | T]) ->
    register(Name, self()),
    do_register(T).
