From 62f0f0ccbcfed2100cc9a5cbc73af43a3035a5e2 Mon Sep 17 00:00:00 2001
From: Feng Lee <feng@emqx.io>
Date: Wed, 28 Aug 2019 11:36:59 +0800
Subject: [PATCH] Add more test cases for 'emqx_misc' module

---
 src/emqx_misc.erl        |  2 +-
 test/emqx_misc_SUITE.erl | 86 +++++++++++++++++++++++++++-------------
 2 files changed, 60 insertions(+), 28 deletions(-)

diff --git a/src/emqx_misc.erl b/src/emqx_misc.erl
index 249d14005..421f881e3 100644
--- a/src/emqx_misc.erl
+++ b/src/emqx_misc.erl
@@ -41,7 +41,7 @@
           ]}).
 
 %% @doc Merge options
--spec(merge_opts(list(), list()) -> list()).
+-spec(merge_opts(Opts, Opts) -> Opts when Opts :: proplists:proplist()).
 merge_opts(Defaults, Options) ->
     lists:foldl(
       fun({Opt, Val}, Acc) ->
diff --git a/test/emqx_misc_SUITE.erl b/test/emqx_misc_SUITE.erl
index a8337c060..677b25c17 100644
--- a/test/emqx_misc_SUITE.erl
+++ b/test/emqx_misc_SUITE.erl
@@ -22,60 +22,92 @@
 -include_lib("eunit/include/eunit.hrl").
 
 -define(SOCKOPTS, [binary,
-                   {packet,    raw},
+                   {packet, raw},
                    {reuseaddr, true},
-                   {backlog,   512},
-                   {nodelay,   true}]).
+                   {backlog, 512},
+                   {nodelay, true}
+                  ]).
 
 all() -> emqx_ct:all(?MODULE).
 
-t_merge_opts() ->
+t_merge_opts(_) ->
     Opts = emqx_misc:merge_opts(?SOCKOPTS, [raw,
                                             binary,
                                             {backlog, 1024},
                                             {nodelay, false},
                                             {max_clients, 1024},
-                                            {acceptors, 16}]),
+                                            {acceptors, 16}
+                                           ]),
     ?assertEqual(1024, proplists:get_value(backlog, Opts)),
     ?assertEqual(1024, proplists:get_value(max_clients, Opts)),
-    [binary, raw,
-     {acceptors, 16},
-     {backlog, 1024},
-     {max_clients, 1024},
-     {nodelay, false},
-     {packet, raw},
-     {reuseaddr, true}] = lists:sort(Opts).
+    ?assertEqual([binary, raw,
+                  {acceptors, 16},
+                  {backlog, 1024},
+                  {max_clients, 1024},
+                  {nodelay, false},
+                  {packet, raw},
+                  {reuseaddr, true}], lists:sort(Opts)).
 
-t_timer_cancel_flush() ->
+t_maybe_apply(_) ->
+    ?assertEqual(undefined, emqx_misc:maybe_apply(fun(A) -> A end, undefined)),
+    ?assertEqual(a, emqx_misc:maybe_apply(fun(A) -> A end, a)).
+
+t_run_fold(_) ->
+    ?assertEqual(1, emqx_misc:run_fold([], 1, state)),
+    Add = fun(I, St) -> I+St end,
+    Mul = fun(I, St) -> I*St end,
+    ?assertEqual(6, emqx_misc:run_fold([Add, Mul], 1, 2)).
+
+t_pipeline(_) ->
+    ?assertEqual({ok, input, state}, emqx_misc:pipeline([], input, state)),
+    Funs = [fun(_I, _St) -> ok end,
+            fun(_I, St)  -> {ok, St+1} end,
+            fun(I, St)   -> {ok, I+1, St+1} end,
+            fun(I, St)   -> {ok, I*2, St*2} end],
+    ?assertEqual({ok, 4, 6}, emqx_misc:pipeline(Funs, 1, 1)).
+
+t_start_timer(_) ->
+    TRef = emqx_misc:start_timer(1, tmsg),
+    timer:sleep(2),
+    ?assertEqual([{timeout, TRef, tmsg}], drain()),
+    ok = emqx_misc:cancel_timer(TRef).
+
+t_cancel_timer(_) ->
     Timer = emqx_misc:start_timer(0, foo),
     ok = emqx_misc:cancel_timer(Timer),
-    receive
-        {timeout, Timer, foo} ->
-            error(unexpected)
-    after 0 -> ok
-    end.
+    ?assertEqual([], drain()).
 
 t_proc_name(_) ->
-    'TODO'.
+    ?assertEqual(emqx_pool_1, emqx_misc:proc_name(emqx_pool, 1)).
 
 t_proc_stats(_) ->
-    'TODO'.
+    Pid1 = spawn(fun() -> exit(normal) end),
+    timer:sleep(10),
+    ?assertEqual([], emqx_misc:proc_stats(Pid1)),
+    Pid2 = spawn(fun() -> timer:sleep(100) end),
+    Pid2 ! msg,
+    timer:sleep(10),
+    ?assertMatch([{mailbox_len, 1}|_], emqx_misc:proc_stats(Pid2)).
 
 t_drain_deliver(_) ->
-    'TODO'.
+    self() ! {deliver, t1, m1},
+    self() ! {deliver, t2, m2},
+    ?assertEqual([{deliver, t1, m1},
+                  {deliver, t2, m2}
+                 ], emqx_misc:drain_deliver()).
 
 t_drain_down(_) ->
-    'TODO'.
+    {Pid1, _Ref1} = erlang:spawn_monitor(fun() -> ok end),
+    {Pid2, _Ref2} = erlang:spawn_monitor(fun() -> ok end),
+    timer:sleep(100),
+    ?assertEqual([Pid1, Pid2], emqx_misc:drain_down(2)).
 
-%% drain self() msg queue for deterministic test behavior
 drain() ->
-    _ = drain([]), % maybe log
-    ok.
+    drain([]).
 
 drain(Acc) ->
     receive
-        Msg ->
-            drain([Msg | Acc])
+        Msg -> drain([Msg|Acc])
     after
         0 ->
             lists:reverse(Acc)