I was trying to learn testing in Erlang. I used the code base of a tic-tac-toe game present at this link. It is a two player game(let's call it a pair of players).I basically wanted to check that what happens when multiple pairs play this game simultaneously.
So I tried writing a basic and a simple module to test it called testing which is as follows:
-module(testing).
%% ====================================================================
%% API functions
%% ====================================================================
-export([all/0]).
%% ====================================================================
%% Internal functions
%% ====================================================================
all()->
test1(),
timer:sleep(75),
test2(),
timer:sleep(75),
test3(),
timer:sleep(75).
test1()->
G_serv_Output1=gameserver:start(),
io:format("Value of G_serv_Output in test1 is ~p~n",
[G_serv_Output1]),
Abhishek=gameclient:login("Abhishek"),
Dharun=gameclient:login("Dharun"),
gameclient:new_game(Abhishek,"Dharun"),
timer:sleep(5),
gameclient:make_move(Abhishek,"Dharun", a1),
timer:sleep(5),
gameclient:make_move(Dharun,"Abhishek", b2),
timer:sleep(5),
gameclient:make_move(Abhishek,"Dharun", a2),
timer:sleep(5),
gameclient:make_move(Dharun,"Abhishek", c3),
timer:sleep(5),
gameclient:make_move(Abhishek,"Dharun", a3).
test2()->
G_serv_Output1=gameserver:start(),
io:format("Value of G_serv_Output in test2 is ~p~n",
[G_serv_Output1]),
Abhijeet=gameclient:login("Abhijeet"),
Ranjan=gameclient:login("Ranjan"),
gameclient:new_game(Abhijeet,"Ranjan"),
timer:sleep(5),
gameclient:make_move(Abhijeet,"Ranjan", a1),
timer:sleep(5),
gameclient:make_move(Ranjan,"Abhijeet", b2),
timer:sleep(5),
gameclient:make_move(Abhijeet,"Ranjan", a2),
timer:sleep(5),
gameclient:make_move(Ranjan,"Abhijeet", c3),
timer:sleep(5),
gameclient:make_move(Abhijeet,"Ranjan", a3).
test3()->
G_serv_Output1=gameserver:start(),
io:format("Value of G_serv_Output in test3 is ~p~n",
[G_serv_Output1]),
Bana=gameclient:login("Bana"),
Sagar=gameclient:login("Sagar"),
gameclient:new_game(Bana,"Sagar"),
timer:sleep(5),
gameclient:make_move(Bana,"Sagar", a1),
timer:sleep(5),
gameclient:make_move(Sagar,"Bana", b2),
timer:sleep(5),
gameclient:make_move(Bana,"Sagar", a2),
timer:sleep(5),
gameclient:make_move(Sagar,"Bana", c3),
timer:sleep(5),
gameclient:make_move(Bana,"Sagar", a3).
All the three tests ran fine and I saw all the three games completing.
Then I noticed that the functions like gameclient:new_game/2 and gameclient:new_game/3 were also taking in Opponent name as input, which I decided to remove so I changed new_game/2 to new_game/1 and make_move/3 to make_move/2 in gameclient as follows:
new_game(Pid) ->
Pid ! {new_game}.
make_move(Pid, Move) ->
Pid ! { make_move, Move }.
loop(Name) ->
receive
{ new_game} ->
gameserver:new_game(Name),
loop(Name);
{ make_move, Move } ->
gameserver:make_move(Name, Move),
loop(Name)
end.
and in gameserver module as:
new_game(Name) ->
global:send(?SERVER, { new_game, Name}).
make_move(Name, Move) ->
global:send(?SERVER, { make_move, Name, Move }).
game_loop(Players, Games) ->
process_flag(trap_exit, true),
receive
{ new_game, Name} ->
PlayerList=dict:fetch_keys(Players),
PlayerAndOpponent=lists:partition(fun(A)->Name==A end, PlayerList),
{_,OpponentNameList}=PlayerAndOpponent,
OpponentName=list_to_tuple(OpponentNameList),
case dict:find(Name, Players) of
{ ok, Pid } ->
case dict:find(element(1,OpponentName), Players) of
{ ok, OpponentPid} ->
Pid ! { msg, "Ready to rumble against " ++ element(1,OpponentName) ++ "!" },
OpponentPid ! { msg, "Ready to rumble against " ++ Name ++ "!" },
GamePid = tictactoe:start({Pid, Name}, {OpponentPid, element(1,OpponentName)}),
GameKey = create_game_key(Name, element(1,OpponentName)),
link(GamePid),
game_loop(Players, dict:store(GameKey, GamePid, Games));
error ->
Pid ! { msg, "Did not find opponent " ++ OpponentName ++ "!" },
game_loop(Players, Games)
end;
error ->
io:format("Could not find player ~p~n", [ Name ]),
game_loop(Players, Games)
end;
{ make_move, Name, Move } ->
PlayerList=dict:fetch_keys(Players),
PlayerAndOpponent=lists:partition(fun(A)->Name==A end, PlayerList),
{_,OpponentNameList}=PlayerAndOpponent,
OpponentName=list_to_tuple(OpponentNameList),
case dict:find(create_game_key(Name, element(1,OpponentName)), Games) of
{ ok, GamePid } ->
tictactoe:make_move(GamePid, Name, Move),
game_loop(Players, Games);
error ->
game_loop(Players, Games)
end
end.
leaving rest of the code in both the modules unchanged.
But Now when I ran the module I found that only test1 ran successfully and test2 and test3 didn't. I tried finding the reason for this and I found that when test2 and test3 start the names of the player from test1 was still in the dict, but since I have called gameserver:start/0 in all the three tests this shouldn't be happening.
Questions:
If I have to test this tictactoe game for two users but they must be playing concurrently then how should my test case module be like?
After EDIT
I looked into erlang's common_test library and implemented it on my same problem
by creating a new module testing2 as follows:
-module(testing2).
-include_lib("common_test/include/ct.hrl").
%% ====================================================================
%% API functions
%% ====================================================================
-export([all/0, groups/0, init_per_group/2, end_per_group/2]).
-export([test1/1,test2/1]).
%% ====================================================================
%% Internal functions
%% ====================================================================
all() -> [{group, session}].
groups() -> [{session,
[],
[{group, clients}]},
{clients,
[parallel, {repeat, 1}],
[test1, test2]}].
init_per_group(session, Config) ->
gameserver:start(),
Config;
init_per_group(_, Config) ->
Config.
end_per_group(session, _Config) ->
gameserver:stop();
end_per_group(_, _Config) ->
ok.
test1(_Config)->
Abhishek=gameclient:login("Abhishek"),
Dharun=gameclient:login("Dharun"),
gameclient:new_game(Abhishek),
timer:sleep(10),
gameclient:make_move(Abhishek, a1),
timer:sleep(10),
gameclient:make_move(Dharun, b2),
timer:sleep(10),
gameclient:make_move(Abhishek, a2),
timer:sleep(10),
gameclient:make_move(Dharun, c3),
timer:sleep(10),
gameclient:make_move(Abhishek, a3).
test2(_Config)->
Abhijeet=gameclient:login("Abhijeet"),
Ranjan=gameclient:login("Ranjan"),
gameclient:new_game(Abhijeet),
timer:sleep(10),
gameclient:make_move(Abhijeet, a1),
timer:sleep(10),
gameclient:make_move(Ranjan, b2),
timer:sleep(10),
gameclient:make_move(Abhijeet, a2),
timer:sleep(10),
gameclient:make_move(Ranjan, c3),
timer:sleep(10),
gameclient:make_move(Abhijeet, a3).
But when I see in the html logs generated by ct I still cannot see these games running but instead I see the following In test1
=== Started at 2017-09-19 11:48:08
"Welcome to tictactoe server!"
"Welcome to tictactoe server!"
"Ready to rumble against Abhishek!"
"Ready to rumble against Dharun!"
=== Ended at 2017-09-19 11:48:08
=== successfully completed test case
=== Returned value: {make_move,a3}
and in test2
=== Started at 2017-09-19 11:48:08
"Welcome to tictactoe server!"
"Welcome to tictactoe server!"
"Ready to rumble against Ranjan!"
"Ready to rumble against Abhijeet!"
"It is not your turn yet!"
"It is not your turn yet!"
=== Ended at 2017-09-19 11:48:08
=== successfully completed test case
=== Returned value: {make_move,a3}
Please help me out here.