Merge branch 'anders/diameter/decode_format/OTP-14511' into maint

* anders/diameter/decode_format/OTP-14511:
  Map less in traffic suite
  Fix decode_format doc oversights
  Rename decode_format false to none
  Tweak {decode_format, false} semantics
  Fix dialyzer spec

5 files changed, 41 insertions, 29 deletions

diff --git a/lib/diameter/src/base/diameter.erl b/lib/diameter/src/base/diameter.erl
index 3b41feac0d..69ef6f4ec0 100644
--- a/lib/diameter/src/base/diameter.erl
+++ b/lib/diameter/src/base/diameter.erl
@@ -340,7 +340,7 @@ call(SvcName, App, Message) ->
    :: record
     | list
     | map
-    | false
+    | none
     | record_from_map.
 
 -type strict_arities()
diff --git a/lib/diameter/src/base/diameter_config.erl b/lib/diameter/src/base/diameter_config.erl
index 6fc4277ac8..284f885884 100644
--- a/lib/diameter/src/base/diameter_config.erl
+++ b/lib/diameter/src/base/diameter_config.erl
@@ -588,8 +588,7 @@ opt(service, {K, false})
        K == use_shared_peers;
        K == monitor;
        K == restrict_connections;
-       K == strict_arities;
-       K == decode_format ->
+       K == strict_arities ->
     true;
 
 opt(service, {K, true})
@@ -602,6 +601,7 @@ opt(service, {decode_format, T})
   when T == record;
        T == list;
        T == map;
+       T == none;
        T == record_from_map ->
     true;
 
diff --git a/lib/diameter/src/base/diameter_gen.erl b/lib/diameter/src/base/diameter_gen.erl
index f9172ec59d..0aea982a54 100644
--- a/lib/diameter/src/base/diameter_gen.erl
+++ b/lib/diameter/src/base/diameter_gen.erl
@@ -45,7 +45,7 @@
 -define(THROW(T), throw({?MODULE, T})).
 
 -type parent_name()   :: atom().  %% parent = Message or AVP
--type parent_record() :: tuple(). %%
+-type parent_record() :: tuple() | avp_values() | map().
 -type avp_name()   :: atom().
 -type avp_record() :: tuple().
 -type avp_values() :: [{avp_name(), term()}].
@@ -61,9 +61,7 @@
 %% # encode_avps/3
 %% ---------------------------------------------------------------------------
 
--spec encode_avps(parent_name(),
-                  parent_record() | avp_values() | map(),
-                  map())
+-spec encode_avps(parent_name(), parent_record(), map())
    -> iolist()
     | no_return().
 
@@ -232,7 +230,7 @@ enc(AvpName, Value, Opts, Mod) ->
 %% ---------------------------------------------------------------------------
 
 -spec decode_avps(parent_name(), binary(), map())
-   -> {parent_record(), [avp()], Failed}
+   -> {parent_record() | parent_name(), [avp()], Failed}
  when Failed :: [{5000..5999, #diameter_avp{}}].
 
 decode_avps(Name, Bin, #{module := Mod, decode_format := Fmt} = Opts) ->
@@ -303,7 +301,7 @@ decode(Bin, Code, Vid, DataLen, Pad, M, P, Name, Mod, Fmt, Strict, Opts0,
                                 type = type(NameT),
                                 index = Idx},
 
-            Dec = decode(Data, Name, NameT, Mod, Opts, Avp),         %% decode
+            Dec = decode1(Data, Name, NameT, Mod, Fmt, Opts, Avp),
             Acc = decode(T, Name, Mod, Fmt, Strict, Opts, Idx+1, AM),%% recurse
             acc(Acc, Dec, I, Name, Field, Arity, Strict, Mod, Opts);
         _ ->
@@ -451,10 +449,10 @@ field({AvpName, _}) ->
 field(_) ->
     'AVP'.
 
-%% decode/6
+%% decode1/7
 
 %% AVP not in dictionary.
-decode(_Data, _Name, 'AVP', _Mod, _Opts, Avp) ->
+decode1(_Data, _Name, 'AVP', _Mod, _Fmt, _Opts, Avp) ->
     Avp;
 
 %% 6733, 4.4:
@@ -504,7 +502,7 @@ decode(_Data, _Name, 'AVP', _Mod, _Opts, Avp) ->
 %% defined the RFC's "unrecognized", which is slightly stronger than
 %% "not defined".)
 
-decode(Data, Name, {AvpName, Type}, Mod, Opts, Avp) ->
+decode1(Data, Name, {AvpName, Type}, Mod, Fmt, Opts, Avp) ->
     #{dictionary := AppMod, failed_avp := Failed}
         = Opts,
 
@@ -518,26 +516,39 @@ decode(Data, Name, {AvpName, Type}, Mod, Opts, Avp) ->
     %% list of component AVPs.
 
     try avp_decode(Data, AvpName, Opts, DecMod, Mod) of
-        {Rec, As} when Type == 'Grouped' ->
-            A = Avp#diameter_avp{value = Rec},
-            [A | As];
-        V when Type /= 'Grouped' ->
-            Avp#diameter_avp{value = V}
+        V ->
+            set(Type, Fmt, Avp, V)
     catch
         throw: {?MODULE, T} ->
-            decode_error(Failed, T, Avp);
+            decode_error(Failed, Fmt, T, Avp);
         error: Reason ->
             decode_error(Failed, Reason, Name, Mod, Opts, Avp)
     end.
 
-%% decode_error/3
+%% set/4
+
+set('Grouped', none, Avp, V) ->
+    {_Rec, As} = V,
+    [Avp | As];
+
+set('Grouped', _, Avp, V) ->
+    {Rec, As} = V,
+    [Avp#diameter_avp{value = Rec} | As];
+
+set(_, _, Avp, V) ->
+    Avp#diameter_avp{value = V}.
+
+%% decode_error/4
 %%
 %% Error when decoding a grouped AVP.
 
-decode_error(true, {Rec, _, _}, Avp) ->
+decode_error(true, none, _, Avp) ->
+    Avp;
+
+decode_error(true, _, {Rec, _, _}, Avp) ->
     Avp#diameter_avp{value = Rec};
 
-decode_error(false, {_, ComponentAvps, [{RC,A} | _]}, Avp) ->
+decode_error(false, _, {_, ComponentAvps, [{RC,A} | _]}, Avp) ->
     {RC, [Avp | ComponentAvps], Avp#diameter_avp{data = [A]}}.
 
 %% decode_error/6
@@ -724,8 +735,9 @@ pack(Arity, F, Avp, Mod, [Failed | Rec]) ->
 
 %% set/5
 
-set(_, _, _, _, false = No) ->
-    No;
+set(_, _, _, _, None)
+  when is_atom(None) ->
+    None;
 
 set(1, F, Value, _, Map)
   when is_map(Map) ->
@@ -819,8 +831,8 @@ empty(Name, #{module := Mod} = Opts) ->
 
 %% newrec/4
 
-newrec(false = No, _, _, _) ->
-    No;
+newrec(none, _, Name, _) ->
+    Name;
 
 newrec(record, Mod, Name, T)
   when T /= decode ->
diff --git a/lib/diameter/src/base/diameter_traffic.erl b/lib/diameter/src/base/diameter_traffic.erl
index c719ef4739..1a4bb4d0bf 100644
--- a/lib/diameter/src/base/diameter_traffic.erl
+++ b/lib/diameter/src/base/diameter_traffic.erl
@@ -1993,10 +1993,10 @@ avp_decode(Dict, 'Experimental-Result' = N, #diameter_avp{data = Bin}
     {V,_} = Dict:avp(decode, Bin, N, decode_opts(Dict)),
     Avp#diameter_avp{name = N, value = V};
 
-avp_decode(Dict, Name, #diameter_avp{value = X,
+avp_decode(Dict, Name, #diameter_avp{value = undefined,
                                      data = Bin}
                        = Avp)
-  when is_binary(Bin), X == undefined orelse X == false ->
+  when is_binary(Bin) ->
     V = Dict:avp(decode, Bin, Name, decode_opts(Dict)),
     Avp#diameter_avp{name = Name, value = V};
 
diff --git a/lib/diameter/src/base/diameter_watchdog.erl b/lib/diameter/src/base/diameter_watchdog.erl
index bb671e9860..c08e2da672 100644
--- a/lib/diameter/src/base/diameter_watchdog.erl
+++ b/lib/diameter/src/base/diameter_watchdog.erl
@@ -72,7 +72,7 @@
                      restrict := boolean(),
                      suspect := non_neg_integer(), %% OKAY -> SUSPECT
                      okay := non_neg_integer()},   %% REOPEN -> OKAY
-         codec :: #{decode_format := false,
+         codec :: #{decode_format := none,
                     string_decode := false,
                     strict_arities => diameter:strict_arities(),
                     strict_mbit := boolean(),
@@ -157,7 +157,7 @@ i({Ack, T, Pid, {Opts,
                                  string_decode,
                                  rfc,
                                  ordered_encode],
-                                SvcOpts#{decode_format := false,
+                                SvcOpts#{decode_format := none,
                                          string_decode := false,
                                          ordered_encode => false})}.