Change code_change/4 to {ok,State,Data}

3 files changed, 16 insertions, 7 deletions

diff --git a/lib/stdlib/doc/src/gen_statem.xml b/lib/stdlib/doc/src/gen_statem.xml
index 04b80d29ac..01be3099c1 100644
--- a/lib/stdlib/doc/src/gen_statem.xml
+++ b/lib/stdlib/doc/src/gen_statem.xml
@@ -241,7 +241,7 @@ stop() ->
 terminate(_Reason, _State, _Data) ->
     void.
 code_change(_Vsn, State, Data, _Extra) ->
-    {ok,{State,Data}}.
+    {ok,State,Data}.
 init([]) ->
     %% Set the callback mode and initial state + data.
     %% Data is used only as a counter.
@@ -1359,7 +1359,7 @@ ok
         <v>&nbsp;&nbsp;Vsn = term()</v>
         <v>OldState = NewState = term()</v>
         <v>Extra = term()</v>
-	<v>Result = {ok,{NewState,NewData}} | Reason</v>
+	<v>Result = {ok,NewState,NewData} | Reason</v>
 	<v>
 	  OldState = NewState =
 	  <seealso marker="#type-state">state()</seealso>
diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl
index 17d361efc2..cc09efc140 100644
--- a/lib/stdlib/src/gen_statem.erl
+++ b/lib/stdlib/src/gen_statem.erl
@@ -200,7 +200,7 @@
 	    OldState :: state(),
 	    OldData :: data(),
 	    Extra :: term()) ->
-    {ok, {NewState :: state(), NewData :: data()}}.
+    {ok, NewState :: state(), NewData :: data()}.
 
 %% Format the callback module state in some sensible that is
 %% often condensed way.  For StatusOption =:= 'normal' the perferred
@@ -619,7 +619,7 @@ system_code_change(
 	    Result -> Result
 	end
     of
-	{ok,{NewState,NewData}} ->
+	{ok,NewState,NewData} ->
 	    {ok,
 	     S#{
 	       state := NewState,
diff --git a/lib/stdlib/test/gen_statem_SUITE.erl b/lib/stdlib/test/gen_statem_SUITE.erl
index f605f0c7b9..573a64bbb7 100644
--- a/lib/stdlib/test/gen_statem_SUITE.erl
+++ b/lib/stdlib/test/gen_statem_SUITE.erl
@@ -55,7 +55,7 @@ groups() ->
      {abnormal, [], [abnormal1, abnormal2]},
      {abnormal_handle_event, [], [abnormal1, abnormal2]},
      {sys, [],
-      [sys1,
+      [sys1, code_change,
        call_format_status,
        error_format_status, terminate_crash_format,
        get_state, replace_state]},
@@ -633,6 +633,15 @@ sys1(Config) ->
     sys:resume(Pid),
     stop_it(Pid).
 
+code_change(Config) ->
+    {ok,Pid} = gen_statem:start(?MODULE, start_arg(Config, []), []),
+    {idle,data} = sys:get_state(Pid),
+    sys:suspend(Pid),
+    sys:change_code(Pid, ?MODULE, old_vsn, extra),
+    sys:resume(Pid),
+    {idle,{old_vsn,data,extra}} = sys:get_state(Pid),
+    stop_it(Pid).
+
 call_format_status(Config) ->
     {ok,Pid} = gen_statem:start(?MODULE, start_arg(Config, []), []),
     Status = sys:get_status(Pid),
@@ -1550,8 +1559,8 @@ wrap_result(Result) ->
 
 
 
-code_change(_OldVsn, State, Data, _Extra) ->
-    {ok,State,Data}.
+code_change(OldVsn, State, Data, Extra) ->
+    {ok,State,{OldVsn,Data,Extra}}.
 
 format_status(terminate, [_Pdict,State,Data]) ->
     {formatted,State,Data};