Test environment can execute tests.

rebar.config

@@ -0,0 +1,41 @@
+%% -*- mode: erlang;erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 ft=erlang et
+
+{lib_dirs, ["deps"]}.
+
+{deps, [
+        {lager, ".*", {git, "git://github.com/basho/lager.git", {branch, "master"}}},
+        {gproc, ".*", %%"0.2.10",
+         {git,"https://github.com/uwiger/gproc.git",
+          {branch, "master"}
+         %% {tag,"v0.2.10"}
+         }},
+        {parse_trans, ".*", {git, "git://github.com/uwiger/parse_trans.git", "master"}},
+        {meck, ".*",
+         {git, "git://github.com/eproxus/meck.git", {branch, "master"}}},
+        {hamcrest, ".*",
+         {git, "git://github.com/hyperthunk/hamcrest-erlang.git",
+          {branch, "master"}}}
+       ]}.
+
+{require_otp_vsn, "R14|R15|R16"}.
+
+{clean_files, ["release/chronos"]}.
+
+{erl_opts, [
+            fail_on_warning,
+            debug_info,
+            %%warn_missing_spec,
+            {src_dirs, ["test_"]},
+            {parse_transform, lager_transform}
+           ]}.
+
+{cover_enabled, true}.
+
+{clean_files, ["*.eunit", "ebin/*.beam"]}.
+
+{validate_app_modules, false}.
+
+{sub_dirs, ["src",
+            "test",
+            "release"]}.

src/chronos.app.src

@@ -0,0 +1,10 @@
+%% This is the application resource file (.app file) for the,
+%% application.
+{application, chronos,
+  [{description, "chronos - a timer utility for Erlang"},
+   {vsn, "0.0.1"},
+   {modules, [chronos]},
+   {registered,[]},
+   {applications, [kernel, stdlib, gproc]},
+%%   {mod, {chronos_app,[]}},
+   {start_phases, []}]}.

src/chronos.erl

@@ -11,88 +11,103 @@
 -behaviour(gen_server).
 
 %% API
--export([start_link/0,
-	 start_link/1,
-	 stop/1,
-	 start_timer/4,
-	 stop_timer/2
-	]).
+-export([start_link/1,
+         stop/1,
+         start_timer/4,
+         stop_timer/2
+        ]).
 
 
 
 %% gen_server callbacks
--export([init/1, 
-	 handle_call/3, 
-	 handle_cast/2, 
-	 handle_info/2,
-	 terminate/2, 
-	 code_change/3]).
+-export([init/1,
+         handle_call/3,
+         handle_cast/2,
+         handle_info/2,
+         terminate/2,
+         code_change/3]).
 
 
 %% Types
 -type server_name()   :: atom().
--type server_ref()    :: server_name() | pid().
+%%-type server_ref()    :: server_name() | pid().
 -type timer_name()    :: term().
--type function_name() :: term().
+-type function_name() :: atom().
 -type args()          :: [term()].
--type callback()      :: {module(), function_name(), args()].
+-type callback()      :: {module(), function_name(), args()}.
+-type timer_duration():: pos_integer().
 
--record(state, 
-	{running = []  :: {[timer_name(), reference()]}
-	}).
+-export_type([server_name/0,
+              timer_name/0,
+              timer_duration/0]).
+
+-record(state,
+        {running = []  :: [{timer_name(), reference()}]
+        }).
 
 %%%===================================================================
 %%% API
 %%%===================================================================
 
--start_link(server_name()) -> {'ok',pid()} | 'ignore' | {'error',term()}.    
+-spec start_link(server_name()) -> {'ok', pid()} | 'ignore' | {'error',term()}.
 start_link(ServerName) ->
-    gen_server:start_link({local, ServerName}, ?MODULE, [], []).
+    gen_server:start_link(?MODULE, ServerName, []).
 
--start_link() -> {'ok',pid()} | 'ignore' | {'error',term()}.
-start_link() ->
-    gen_server:start_link(?MODULE, [], []).
+%% -start_link() -> {'ok',pid()} | 'ignore' | {'error',term()}.
+%% start_link() ->
+%%     gen_server:start_link(?MODULE, [], []).
 
 -spec stop(server_name()) -> ok.
-stop(ServerRef) ->
-    gen_server:call(ServerRef, stop).
-		  
--spec start_timer(server_ref(), timer_name(), pos_integer(), callback()) ->
-			 'ok' | {'error',term()}.
-start_timer(ServerRef, TimerName, Timeout, Callback) ->
-    gen_server:call(ServerRef, {start_timer, TimerName, Timeout, Callback}).
-
--spec stop_timer(server_ref(), timer_name()) -> 'ok' | {'error',term()}.
+stop(ServerName) ->
+    call(ServerName, stop).
+
+-spec start_timer(server_name(), timer_name(), pos_integer(), callback()) ->
+                         'ok' | {'error',term()}.
+start_timer(ServerName, TimerName, Timeout, Callback) ->
+    call(ServerName, {start_timer, TimerName, Timeout, Callback}).
+
+-spec stop_timer(server_name(), timer_name()) -> 'ok' | {'error',term()}.
 stop_timer(ServerRef, TimerName) ->
-    gen_server:call(ServerRef, {stop_timer, TimerName}).
-		 
+    call(ServerRef, {stop_timer, TimerName}).
+
 
 
 %%%===================================================================
 %%% gen_server callbacks
 %%%===================================================================
 
 
--spec init([term()]) -> {'ok', #state{}} | {'stop', term()} | 'ignore'.
-init([]) ->
+-spec init(server_name()) -> {'ok', #state{}} | {'stop', term()} | 'ignore'.
+init(ServerName) ->
+    gproc:reg(proc_name(ServerName)),
     {ok, #state{}}.
 
--spec handle_call(term(), term(), #state{}) -> 	
-			 {'reply', 'ok' | {'error', term()} , #state{}} | 
-			 {'stop', term(), 'ok', #state{}}.		 
-handle_call({start_timer, Name, Time, Callback}, _From, 
-	    #state{running=R}=State) ->
-    %% If the Name timer is running we clean it up. 
+-spec handle_call(term(), term(), #state{}) ->
+                         {'reply', 'ok' | {'error', term()} , #state{}} |
+                         {'stop', term(), 'ok', #state{}}.
+handle_call({start_timer, Name, Time, Callback}, _From,
+            #state{running=R}=State) ->
+    %% If the Name timer is running we clean it up.
     R1 = case lists:keytake(Name, 1, R) of
-	     false ->
-		 R;
-	     {value, {_, TRef,}, Ra} ->
-		 erlang:cancel_timer(TRef),
-		 Ra
-	 end,
+             false ->
+                 R;
+             {value, {_, TRef}, Ra} ->
+                 erlang:cancel_timer(TRef),
+                 Ra
+         end,
     TRefNew = erlang:start_timer(Time, self(), {Name,Callback}),
-    {reply, ok, State#state{running=[{Name,TRefNew}|R1]}.
-
+    {reply, ok, State#state{running=[{Name,TRefNew}|R1]}};
+handle_call({stop_timer, Name}, _From,
+            #state{running=R}=State) ->
+    case lists:keytake(Name, 1, R) of
+        {value, {_, TRef}, Rnext} ->
+            erlang:cancel_timer(TRef),
+            {reply, ok, State#state{running=Rnext}};
+        false ->
+            Reason = io_lib:format("Stopping ~p timer that was not running",
+                                   [Name]),
+            {reply, {error, Reason}, State}
+    end.
 %%--------------------------------------------------------------------
 %% @private
 %% @doc
@@ -147,3 +162,14 @@ code_change(_OldVsn, State, _Extra) ->
 %%%===================================================================
 %%% Internal functions
 %%%===================================================================
+
+proc_name(ServerName) -> {n, l, ServerName}.
+
+
+call(ServerName, Msg) ->
+    {Pid, _} = gproc:await(proc_name(ServerName)),
+    gen_server:call(Pid, Msg, infinity).
+
+%% cast(ServerName, Msg) ->
+%%     {Pid, _} = gproc:await(proc_name(ServerName)),
+%%     gen_server:cast(Pid, Msg).

test/chronos_eqc.erl

@@ -0,0 +1,85 @@
+%%% @author Torben Hoffmann <th@issuu.com>
+%%% @copyright (C) 2012, Torben Hoffmann
+%%% @doc
+%%%
+%%% @end
+%%% Created : 13 Feb 2012 by Torben Hoffmann <th@issuu.com>
+
+-module(chronos_eqc).
+
+
+-include_lib("eqc/include/eqc.hrl").
+-include_lib("eqc/include/eqc_statem.hrl").
+
+-compile(export_all).
+
+-record(state,
+        {servers = [],
+         timers = [] :: [{chronos:server_name(), chronos:timer_name()}]
+        }).
+
+%% Initialize the state
+initial_state() ->
+    #state{
+            servers = [],
+            timers = []
+          }.
+
+%% Command generator, S is the state
+command(S) ->
+    frequency( [ {100, {call, timer_expiry, start_server, [server_name()]}} ]
+           ).
+
+%% Next state transformation, S is the current state
+next_state(S,_V,{call,timer_expiry, start_server, [ServerName]}) ->
+    S#state{ servers = [ServerName | S#state.servers] }.
+
+%% Precondition, checked before command is added to the command sequence
+precondition(S,{call,timer_expiry, start_server, [ServerName]}) ->
+    not lists:member(ServerName, S#state.servers).
+
+%% Postcondition, checked after command has been evaluated
+%% OBS: S is the state before next_state(S,_,<command>)
+postcondition(_S,{call,timer_expiry, start_server, [_ServerName]}, ok) ->
+    true;
+postcondition(_S,{call,timer_expiry, start_server, [_ServerName]}, _Other) ->
+    false.
+
+prop_chronos() ->
+    ?FORALL(Cmds,commands(?MODULE),
+            ?TRAPEXIT(
+               begin
+                   start_context(),
+                   {H,S,Res} = run_commands(?MODULE,Cmds),
+                   stop_context(),
+                   ?WHENFAIL(
+                      io:format("History: ~p\nState: ~p\nRes: ~p\n",[H,S,Res]),
+                   Res == ok)
+               end)).
+
+start_context() ->
+    application:start(gproc),
+    timer_expiry:start_link().
+
+stop_context() ->
+    timer_expiry:stop(),
+    application:stop(gproc).
+
+
+
+%%-------------------- GENERATORS ------------------------------
+
+
+server_name() -> {server, nat()}.
+
+timer_name() -> {timer, nat()}.
+
+timer_timeout() -> choose(10, 100).
+
+%%---------------------- OPERATIONS ----------------------
+
+start_server(ServerName) ->
+    chronos:start_link(ServerName).
+
+start_timer(Server, Timer, Timeout) ->
+    ok.