Merge branch 'richcarl/warnings-by-default/OTP-12781'

* richcarl/warnings-by-default/OTP-12781:
  stdlib: Use warning channel in test qlc_SUITE:otp_6964/1
  stdlib: Fix testcase for qlc_SUITE
  kernel: Fix code_SUITE with respect to new logger default
  Map error logger warnings to warning messages by default

7 files changed, 84 insertions, 68 deletions

diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml
index ea94a4e82b..98d05dc7de 100644
--- a/erts/doc/src/erl.xml
+++ b/erts/doc/src/erl.xml
@@ -1322,13 +1322,14 @@
       <item>
         <p>Verbose.</p>
       </item>
-      <tag><c><![CDATA[+W w | i]]></c></tag>
+      <tag><c><![CDATA[+W w | i | e]]></c></tag>
       <item>
         <p>Sets the mapping of warning messages for <c><![CDATA[error_logger]]></c>.
           Messages sent to the error logger using one of the warning
-          routines can be mapped either to errors (default), warnings 
-          (<c><![CDATA[+W w]]></c>), or info reports (<c><![CDATA[+W i]]></c>). The current
-          mapping can be retrieved using
+          routines can be mapped either to errors (<c><![CDATA[+W e]]></c>),
+          warnings (<c><![CDATA[+W w]]></c>), or info reports
+          (<c><![CDATA[+W i]]></c>). The default is warnings.
+          The current mapping can be retrieved using
           <c><![CDATA[error_logger:warning_map/0]]></c>. See
           <seealso marker="kernel:error_logger#warning_map/0">error_logger(3)</seealso>
           for further information.</p>
diff --git a/erts/emulator/beam/erl_init.c b/erts/emulator/beam/erl_init.c
index 988ff0e2b5..33417833a9 100644
--- a/erts/emulator/beam/erl_init.c
+++ b/erts/emulator/beam/erl_init.c
@@ -625,7 +625,7 @@ void erts_usage(void)
 
     erts_fprintf(stderr, "-v             turn on chatty mode (GCs will be reported etc)\n");
 
-    erts_fprintf(stderr, "-W<i|w>        set error logger warnings mapping,\n");
+    erts_fprintf(stderr, "-W<i|w|e>      set error logger warnings mapping,\n");
     erts_fprintf(stderr, "               see error_logger documentation for details\n");
     erts_fprintf(stderr, "-zdbbl size    set the distribution buffer busy limit in kilobytes\n");
     erts_fprintf(stderr, "               valid range is [1-%d]\n", INT_MAX/1024);
@@ -1253,7 +1253,7 @@ erl_start(int argc, char **argv)
     verbose = DEBUG_DEFAULT;
 #endif
 
-    erts_error_logger_warnings = am_error;
+    erts_error_logger_warnings = am_warning;
 
     while (i < argc) {
 	if (argv[i][0] != '-') {
@@ -1991,11 +1991,12 @@ erl_start(int argc, char **argv)
 	    case 'i':
 		erts_error_logger_warnings = am_info;
 		break;
+	    case 'e':
+		erts_error_logger_warnings = am_error;
+		break;
 	    case 'w':
 		erts_error_logger_warnings = am_warning;
 		break;
-	    case 'e': /* The default */
-		erts_error_logger_warnings = am_error;
 	    default:
 		erts_fprintf(stderr, "unrecognized warning_map option %s\n", arg);
 		erts_usage();
diff --git a/erts/etc/common/erlexec.c b/erts/etc/common/erlexec.c
index 23226909a7..d6544a2829 100644
--- a/erts/etc/common/erlexec.c
+++ b/erts/etc/common/erlexec.c
@@ -1172,7 +1172,7 @@ usage_aux(void)
 	  "[+S NO_SCHEDULERS:NO_SCHEDULERS_ONLINE] "
 	  "[+SP PERCENTAGE_SCHEDULERS:PERCENTAGE_SCHEDULERS_ONLINE] "
 	  "[+T LEVEL] [+V] [+v] "
-	  "[+W<i|w>] [+z MISC_OPTION] [args ...]\n");
+	  "[+W<i|w|e>] [+z MISC_OPTION] [args ...]\n");
   exit(1);
 }
 
diff --git a/lib/kernel/doc/src/error_logger.xml b/lib/kernel/doc/src/error_logger.xml
index df2f0b01ee..f49d63b5a6 100644
--- a/lib/kernel/doc/src/error_logger.xml
+++ b/lib/kernel/doc/src/error_logger.xml
@@ -58,12 +58,11 @@
       specific events. (<c>add_report_handler/1,2</c>). Also, there is
       a useful event handler in STDLIB for multi-file logging of events,
       see <c>log_mf_h(3)</c>.</p>
-    <p>Warning events were introduced in Erlang/OTP R9C. To retain
-      backwards compatibility, these are by default tagged as errors,
-      thus showing up as error reports in the logs. By using
-      the command line flag <c><![CDATA[+W <w | i>]]></c>, they can instead
-      be tagged as warnings or info. Tagging them as warnings may
-      require rewriting existing user defined event handlers.</p>
+    <p>Warning events were introduced in Erlang/OTP R9C and are enabled
+      by default as of 18.0. To retain backwards compatibility with existing
+      user defined event handlers, these may be tagged as errors or info
+      using the command line flag <c><![CDATA[+W <e | i | w>]]></c>, thus
+      showing up as error or info reports in the logs.</p>
   </description>
   <datatypes>
     <datatype>
@@ -132,7 +131,7 @@ ok</pre>
       <desc>
         <p>Returns the current mapping for warning events. Events sent
           using <c>warning_msg/1,2</c> or <c>warning_report/1,2</c>
-          are tagged as errors (default), warnings or info, depending
+          are tagged as errors, warnings (default) or info, depending
           on the value of the command line flag <c>+W</c>.</p>
         <pre>
 os$ <input>erl</input>
@@ -140,25 +139,25 @@ Erlang (BEAM) emulator version 5.4.8 [hipe] [threads:0] [kernel-poll]
 
 Eshell V5.4.8  (abort with ^G)
 1> <input>error_logger:warning_map().</input>
-error
-2> <input>error_logger:warning_msg("Warnings tagged as: ~p~n", [error]).</input>
+warning
+2> <input>error_logger:warning_msg("Warnings tagged as: ~p~n", [warning]).</input>
 
-=ERROR REPORT==== 11-Aug-2005::15:31:23 ===
-Warnings tagged as: error
+=WARNING REPORT==== 11-Aug-2005::15:31:55 ===
+Warnings tagged as: warning
 ok
 3> 
 User switch command
  --> q
-os$ <input>erl +W w</input>
+os$ <input>erl +W e</input>
 Erlang (BEAM) emulator version 5.4.8 [hipe] [threads:0] [kernel-poll]
 
 Eshell V5.4.8  (abort with ^G)
 1> <input>error_logger:warning_map().</input>
-warning
-2> <input>error_logger:warning_msg("Warnings tagged as: ~p~n", [warning]).</input>
+error
+2> <input>error_logger:warning_msg("Warnings tagged as: ~p~n", [error]).</input>
 
-=WARNING REPORT==== 11-Aug-2005::15:31:55 ===
-Warnings tagged as: warning
+=ERROR REPORT==== 11-Aug-2005::15:31:23 ===
+Warnings tagged as: error
 ok</pre>
       </desc>
     </func>
diff --git a/lib/kernel/test/code_SUITE.erl b/lib/kernel/test/code_SUITE.erl
index 549c65d034..c82aaf0582 100644
--- a/lib/kernel/test/code_SUITE.erl
+++ b/lib/kernel/test/code_SUITE.erl
@@ -1654,9 +1654,7 @@ get_mode(Config) when is_list(Config) ->
 init(Tester) ->
     {ok, Tester}.
 
-handle_event({error, _GL, {emulator, _, _}}, Tester) ->
-    {ok, Tester};
-handle_event({error, _GL, Msg}, Tester) ->
+handle_event({warning_msg, _GL, Msg}, Tester) ->
     Tester ! Msg,
     {ok, Tester};
 handle_event(_Event, State) ->
diff --git a/lib/kernel/test/error_logger_warn_SUITE.erl b/lib/kernel/test/error_logger_warn_SUITE.erl
index 2bf467610e..fb576d77a3 100644
--- a/lib/kernel/test/error_logger_warn_SUITE.erl
+++ b/lib/kernel/test/error_logger_warn_SUITE.erl
@@ -21,8 +21,8 @@
 -export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1, 
 	 init_per_group/2,end_per_group/2,
 	 init_per_testcase/2,end_per_testcase/2,
-	 basic/1,warnings_info/1,warnings_warnings/1,
-	 rb_basic/1,rb_warnings_info/1,rb_warnings_warnings/1,
+	 basic/1,warnings_info/1,warnings_errors/1,
+	 rb_basic/1,rb_warnings_info/1,rb_warnings_errors/1,
 	 rb_trunc/1,rb_utc/1,file_utc/1]).
 
 %% Internal exports.
@@ -48,8 +48,8 @@
 suite() -> [{ct_hooks,[ts_install_cth]}].
 
 all() -> 
-    [basic, warnings_info, warnings_warnings, rb_basic,
-     rb_warnings_info, rb_warnings_warnings, rb_trunc,
+    [basic, warnings_info, warnings_errors, rb_basic,
+     rb_warnings_info, rb_warnings_errors, rb_trunc,
      rb_utc, file_utc].
 
 groups() -> 
@@ -88,11 +88,11 @@ warnings_info(Config) when is_list(Config) ->
     put(elw_config,Config),
     warnings_info().
 
-warnings_warnings(doc) ->
-    ["Tests mapping warnings to warnings functionality"];
-warnings_warnings(Config) when is_list(Config) ->
+warnings_errors(doc) ->
+    ["Tests mapping warnings to errors functionality"];
+warnings_errors(Config) when is_list(Config) ->
     put(elw_config,Config),
-    warnings_warnings().
+    warnings_errors().
 
 rb_basic(doc) ->
     ["Tests basic rb functionality"];
@@ -106,11 +106,11 @@ rb_warnings_info(Config) when is_list(Config) ->
     put(elw_config,Config),
     rb_warnings_info().
 
-rb_warnings_warnings(doc) ->
-    ["Tests warnings as warnings rb functionality"];
-rb_warnings_warnings(Config) when is_list(Config) ->
+rb_warnings_errors(doc) ->
+    ["Tests warnings as errors rb functionality"];
+rb_warnings_errors(Config) when is_list(Config) ->
     put(elw_config,Config),
-    rb_warnings_warnings().
+    rb_warnings_errors().
 
 rb_trunc(doc) ->
     ["Tests rb functionality on truncated data"];
@@ -159,6 +159,9 @@ install_relay(Node) ->
     rpc:call(Node,error_logger,add_report_handler,[?MODULE,[self()]]).
 
 
+warning_map(Node) ->
+    rpc:call(Node,error_logger,warning_map,[]).
+
 format(Node,A,B) ->
     rpc:call(Node,error_logger,format,[A,B]).
 error_msg(Node,A,B) ->
@@ -185,19 +188,20 @@ basic() ->
     ?line ok = install_relay(Node),
     ?line Self = self(),
     ?line GL = group_leader(),
+    ?line warning = warning_map(Node),
     ?line format(Node,"~p~n",[Self]),
     ?line ?EXPECT({handle_event,{error,GL,{_,"~p~n",[Self]}}}),
     ?line error_msg(Node,"~p~n",[Self]),
     ?line ?EXPECT({handle_event,{error,GL,{_,"~p~n",[Self]}}}),
     ?line warning_msg(Node,"~p~n",[Self]),
-    ?line ?EXPECT({handle_event,{error,GL,{_,"~p~n",[Self]}}}),
+    ?line ?EXPECT({handle_event,{warning_msg,GL,{_,"~p~n",[Self]}}}),
     ?line info_msg(Node,"~p~n",[Self]),
     ?line ?EXPECT({handle_event,{info_msg,GL,{_,"~p~n",[Self]}}}),
     ?line Report = [{self,Self},{gl,GL},make_ref()],
     ?line error_report(Node,Report),
     ?line ?EXPECT({handle_event,{error_report,GL,{_,std_error,Report}}}),
     ?line warning_report(Node,Report),
-    ?line ?EXPECT({handle_event,{error_report,GL,{_,std_error,Report}}}),
+    ?line ?EXPECT({handle_event,{warning_report,GL,{_,std_warning,Report}}}),
     ?line info_report(Node,Report),
     ?line ?EXPECT({handle_event,{info_report,GL,{_,std_info,Report}}}),
 
@@ -209,6 +213,7 @@ warnings_info() ->
     ?line ok = install_relay(Node),
     ?line Self = self(),
     ?line GL = group_leader(),
+    ?line info = warning_map(Node),
     ?line Report = [{self,Self},{gl,GL},make_ref()],
     ?line warning_msg(Node,"~p~n",[Self]),
     ?line ?EXPECT({handle_event,{info_msg,GL,{_,"~p~n",[Self]}}}),
@@ -217,16 +222,17 @@ warnings_info() ->
     ?line stop_node(Node),
     ok.
 
-warnings_warnings() ->    
-    ?line Node = start_node(nn(),"+Ww"),
+warnings_errors() ->    
+    ?line Node = start_node(nn(),"+We"),
     ?line ok = install_relay(Node),
     ?line Self = self(),
     ?line GL = group_leader(),
+    ?line error = warning_map(Node),
     ?line Report = [{self,Self},{gl,GL},make_ref()],
     ?line warning_msg(Node,"~p~n",[Self]),
-    ?line ?EXPECT({handle_event,{warning_msg,GL,{_,"~p~n",[Self]}}}),
+    ?line ?EXPECT({handle_event,{error,GL,{_,"~p~n",[Self]}}}),
     ?line warning_report(Node,Report),
-    ?line ?EXPECT({handle_event,{warning_report,GL,{_,std_warning,Report}}}),
+    ?line ?EXPECT({handle_event,{error_report,GL,{_,std_error,Report}}}),
     ?line stop_node(Node),
     ok.
     
@@ -356,6 +362,7 @@ rb_basic() ->
 		      "error_logger_mf_maxfiles 5"),
     ?line Self = self(),
     ?line GL = group_leader(),
+    ?line warning = warning_map(Node),
     ?line Report = [{self,Self},{gl,GL},make_ref()],
     ?line fake_gl(Node,warning_msg,"~p~n",[Self]),
     ?line fake_gl(Node,warning_report,Report),
@@ -363,10 +370,14 @@ rb_basic() ->
     ?line application:start(sasl),
     ?line rb:start([{report_dir, rd()}]),
     ?line rb:list(),
-    ?line true = (one_rb_lines([error]) > 1),
-    ?line true = (one_rb_lines([error_report]) > 1),
-    ?line 1 = one_rb_findstr([error],pid_to_list(Self)),
-    ?line 1 = one_rb_findstr([error_report],pid_to_list(Self)),
+    ?line true = (one_rb_lines([error]) =:= 0),
+    ?line true = (one_rb_lines([error_report]) =:= 0),
+    ?line 0 = one_rb_findstr([error],pid_to_list(Self)),
+    ?line 0 = one_rb_findstr([error_report],pid_to_list(Self)),
+    ?line 1 = one_rb_findstr([warning_msg],pid_to_list(Self)),
+    ?line 1 = one_rb_findstr([warning_report],pid_to_list(Self)),
+    ?line 0 = one_rb_findstr([info_msg],pid_to_list(Self)),
+    ?line 0 = one_rb_findstr([info_report],pid_to_list(Self)),
     ?line 2 = one_rb_findstr([],pid_to_list(Self)),
     ?line true = (one_rb_findstr([progress],"===") > 4),
     ?line rb:stop(),
@@ -381,6 +392,7 @@ rb_warnings_info() ->
 		      "error_logger_mf_maxfiles 5"),
     ?line Self = self(),
     ?line GL = group_leader(),
+    ?line info = warning_map(Node),
     ?line Report = [{self,Self},{gl,GL},make_ref()],
     ?line fake_gl(Node,warning_msg,"~p~n",[Self]),
     ?line fake_gl(Node,warning_report,Report),
@@ -403,13 +415,14 @@ rb_warnings_info() ->
     ?line stop_node(Node),
     ok.
 
-rb_warnings_warnings() ->
+rb_warnings_errors() ->
     ?line clean_rd(),
-    ?line Node = start_node(nn(),"+W w -boot start_sasl -sasl error_logger_mf_dir "++
+    ?line Node = start_node(nn(),"+W e -boot start_sasl -sasl error_logger_mf_dir "++
 		      quote(rd())++" error_logger_mf_maxbytes 5000 "
 		      "error_logger_mf_maxfiles 5"),
     ?line Self = self(),
     ?line GL = group_leader(),
+    ?line error = warning_map(Node),
     ?line Report = [{self,Self},{gl,GL},make_ref()],
     ?line fake_gl(Node,warning_msg,"~p~n",[Self]),
     ?line fake_gl(Node,warning_report,Report),
@@ -417,12 +430,12 @@ rb_warnings_warnings() ->
     ?line application:start(sasl),
     ?line rb:start([{report_dir, rd()}]),
     ?line rb:list(),
-    ?line true = (one_rb_lines([error]) =:= 0),
-    ?line true = (one_rb_lines([error_report]) =:= 0),
-    ?line 0 = one_rb_findstr([error],pid_to_list(Self)),
-    ?line 0 = one_rb_findstr([error_report],pid_to_list(Self)),
-    ?line 1 = one_rb_findstr([warning_msg],pid_to_list(Self)),
-    ?line 1 = one_rb_findstr([warning_report],pid_to_list(Self)),
+    ?line true = (one_rb_lines([error]) > 1),
+    ?line true = (one_rb_lines([error_report]) > 1),
+    ?line 1 = one_rb_findstr([error],pid_to_list(Self)),
+    ?line 1 = one_rb_findstr([error_report],pid_to_list(Self)),
+    ?line 0 = one_rb_findstr([warning_msg],pid_to_list(Self)),
+    ?line 0 = one_rb_findstr([warning_report],pid_to_list(Self)),
     ?line 0 = one_rb_findstr([info_msg],pid_to_list(Self)),
     ?line 0 = one_rb_findstr([info_report],pid_to_list(Self)),
     ?line 2 = one_rb_findstr([],pid_to_list(Self)),
@@ -434,7 +447,7 @@ rb_warnings_warnings() ->
 
 rb_trunc() ->
     ?line clean_rd(),
-    ?line Node = start_node(nn(),"+W w -boot start_sasl -sasl error_logger_mf_dir "++
+    ?line Node = start_node(nn(),"-boot start_sasl -sasl error_logger_mf_dir "++
 		      quote(rd())++" error_logger_mf_maxbytes 5000 "
 		      "error_logger_mf_maxfiles 5"),
     ?line Self = self(),
@@ -467,7 +480,7 @@ rb_trunc() ->
 
 rb_utc() ->
     ?line clean_rd(),
-    ?line Node = start_node(nn(),"+W w -boot start_sasl -sasl error_logger_mf_dir "++
+    ?line Node = start_node(nn(),"-boot start_sasl -sasl error_logger_mf_dir "++
 		      quote(rd())++" error_logger_mf_maxbytes 5000 "
 		      "error_logger_mf_maxfiles 5 -sasl utc_log true"),
     ?line Self = self(),
@@ -500,7 +513,7 @@ rb_utc() ->
     
 file_utc() ->
     ?line file:delete(lf()),
-    ?line SS="+W w -stdlib utc_log true -kernel error_logger "++ oquote("{file,"++iquote(lf())++"}"),
+    ?line SS="-stdlib utc_log true -kernel error_logger "++ oquote("{file,"++iquote(lf())++"}"),
     %erlang:display(SS),
     ?line Node = start_node(nn(),SS),
     %erlang:display(rpc:call(Node,application,get_env,[kernel,error_logger])),
diff --git a/lib/stdlib/test/qlc_SUITE.erl b/lib/stdlib/test/qlc_SUITE.erl
index 348c308f5d..56829fac5c 100644
--- a/lib/stdlib/test/qlc_SUITE.erl
+++ b/lib/stdlib/test/qlc_SUITE.erl
@@ -6120,7 +6120,7 @@ otp_6964(Config) when is_list(Config) ->
               lists:flatten(qlc:format_error(ErrReply)),
           qlc_SUITE:install_error_logger(),
           20000 = length(F(warning_msg)),
-          {error, joining} = qlc_SUITE:read_error_logger(),
+          {warning, joining} = qlc_SUITE:read_error_logger(),
           20000 = length(F(info_msg)),
           {info, joining} = qlc_SUITE:read_error_logger(),
           20000 = length(F(error_msg)),
@@ -6155,8 +6155,8 @@ otp_6964(Config) when is_list(Config) ->
           {error, caching} = qlc_SUITE:read_error_logger(),
           {error, caching} = qlc_SUITE:read_error_logger(),
           1 = length(F(warning_msg)),
-          {error, caching} = qlc_SUITE:read_error_logger(),
-          {error, caching} = qlc_SUITE:read_error_logger(),
+          {warning, caching} = qlc_SUITE:read_error_logger(),
+          {warning, caching} = qlc_SUITE:read_error_logger(),
           1 = length(F(info_msg)),
           {info, caching} = qlc_SUITE:read_error_logger(),
           {info, caching} = qlc_SUITE:read_error_logger(),
@@ -6188,7 +6188,7 @@ otp_6964(Config) when is_list(Config) ->
           L = F(info_msg),
           {info, sorting} = qlc_SUITE:read_error_logger(),
           L = F(warning_msg),
-          {error, sorting} = qlc_SUITE:read_error_logger(),
+          {warning, sorting} = qlc_SUITE:read_error_logger(),
           qlc_SUITE:uninstall_error_logger(),
           ets:delete(E1),
           ets:delete(E2)">>],
@@ -6215,7 +6215,7 @@ otp_6964(Config) when is_list(Config) ->
                        R = lists:sort(F(error_msg)),
                        {error, caching} = qlc_SUITE:read_error_logger(),
                        R = lists:sort(F(warning_msg)),
-                       {error, caching} = qlc_SUITE:read_error_logger(),
+                       {warning, caching} = qlc_SUITE:read_error_logger(),
                        qlc_SUITE:uninstall_error_logger(),
                        ErrReply = F(not_allowed),
                        {error,qlc,{tmpdir_usage,caching}} = ErrReply,
@@ -8178,6 +8178,8 @@ read_error_logger() ->
             {error, Why};
         {info, Why} ->
             {info, Why};
+        {warning, Why} ->
+            {warning, Why};
         {error, Pid, Tuple} ->
             {error, Pid, Tuple}
     after 1000 ->
@@ -8192,8 +8194,7 @@ read_error_logger() ->
 init(Tester) ->
     {ok, Tester}.
     
-handle_event({error, _GL, {_Pid, _Msg, [Why, _]}}, Tester) 
-                     when is_atom(Why) ->
+handle_event({error, _GL, {_Pid, _Msg, [Why, _]}}, Tester) when is_atom(Why) ->
     Tester ! {error, Why},
     {ok, Tester};
 handle_event({error, _GL, {_Pid, _Msg, [P, T]}}, Tester) when is_pid(P) ->
@@ -8202,6 +8203,9 @@ handle_event({error, _GL, {_Pid, _Msg, [P, T]}}, Tester) when is_pid(P) ->
 handle_event({info_msg, _GL, {_Pid, _Msg, [Why, _]}}, Tester) ->
     Tester ! {info, Why},
     {ok, Tester};
+handle_event({warning_msg, _GL, {_Pid, _Msg, [Why, _]}}, Tester) when is_atom(Why) ->
+    Tester ! {warning, Why},
+    {ok, Tester};
 handle_event(_Event, State) ->
     {ok, State}.