fix random number generation when using interval (TSUN-184)

src/test/ts_test_all.erl

@@ -25,4 +25,5 @@ all_test_() -> [ts_test_recorder,
                 ts_test_match,
                 ts_test_mon,
                 ts_test_user_server,
-                ts_test_search].
+                ts_test_search,
+                ts_test_stats].

src/test/ts_test_stats.erl

@@ -0,0 +1,23 @@
+%%%-------------------------------------------------------------------
+%%% File    : ts_test_stats.erl
+%%% Author  : Nicolas Niclausse <nicolas@niclux.org>
+%%% Description :
+%%%
+%%% Created : 12 Jul 2011 by Nicolas Niclausse <nicolas@niclux.org>
+%%%-------------------------------------------------------------------
+-module(ts_test_stats).
+
+-compile(export_all).
+
+-include_lib("eunit/include/eunit.hrl").
+-include_lib("ts_profile.hrl").
+-include_lib("ts_config.hrl").
+
+-define(EPSILON,0.01). % error (used to compare floats)
+
+set_dynvar_random_test() ->
+    Min=1,
+    Max=10,
+    R=lists:map(fun(_)->ts_stats:uniform(Min,Max) end, lists:seq(1,1000)),
+    ?assertEqual(Max,lists:max(R)),
+    ?assertEqual(Min,lists:min(R)).

src/tsung/ts_client.erl

@@ -451,7 +451,7 @@ set_dynvars(erlang,{Module,Callback},_Vars,DynData) ->
 set_dynvars(code,Fun,_Vars,DynData) ->
     Fun({self(),DynData#dyndata.dynvars});
 set_dynvars(random,{number,Start,End},Vars,_DynData) ->
-    lists:map(fun(_) -> integer_to_list(Start+random:uniform(End-Start)) end,Vars);
+    lists:map(fun(_) -> integer_to_list(ts_stats:uniform(Start,End)) end,Vars);
 set_dynvars(random,{string,Length},Vars,_DynData) ->
     R = fun(_) -> ts_utils:randomstr(Length) end,
     lists:map(R,Vars);

src/tsung/ts_stats.erl

@@ -54,7 +54,7 @@ sample (F, X, Param, N) ->
     sample(F, [F(Param)|X], Param, N-1 ).
 
 uniform(Min,Max)->
-    Min+random:uniform(Max-Min).
+    Min+random:uniform(Max-Min+1)-1.
 
 %% random sample from an exponential distribution
 exponential(Param) ->