change nil handling in jsx mode: fixes #27

Author: kuenishi

src/msgpack.erl

@@ -173,7 +173,7 @@ enable_str_test() ->
     ?assertEqual(<<167:8, (<<"saitama">>)/binary >>,
                  msgpack:pack(<<"saitama">>, [{enable_str, false}])),
     ?assertEqual(<<196,7,115,97,105,116,97,109,97>>,
-                 msgpack:pack(<<"saitama">>, [{enable_str, true}])). 
+                 msgpack:pack(<<"saitama">>, [{enable_str, true}])).
 
 basic_test()->
     Tests = test_data(),

src/msgpack_packer.erl

@@ -32,7 +32,10 @@ pack(I, _) when is_integer(I) ->
     pack_uint(I);
 pack(F, _) when is_float(F) ->
     pack_double(F);
-pack(nil, _) ->
+pack(null, _Opt = ?OPTION{interface=jsx}) ->
+    << 16#C0:8 >>;
+pack(nil, _Opt = ?OPTION{interface=Interface}) 
+  when Interface =/= jsx ->
     << 16#C0:8 >>;
 pack(false, _) ->
     << 16#C2:8 >>;

src/msgpack_unpacker.erl

@@ -28,6 +28,8 @@
 %% unpack them all
 -spec unpack_stream(Bin::binary(), msgpack_option()) -> {msgpack:object(), binary()} | no_return().
 %% ATOMS
+unpack_stream(<<16#C0, Rest/binary>>, _Opt = ?OPTION{interface=jsx}) ->
+    {null, Rest};
 unpack_stream(<<16#C0, Rest/binary>>, _) ->
     {nil, Rest};
 unpack_stream(<<16#C2, Rest/binary>>, _) ->

test/msgpack_test.erl

@@ -146,6 +146,17 @@ issue_jiffy_5_test() ->
     ?assertEqual(Term, Decoded).
 
 
+issue_27_test_() ->
+    [?_assertEqual({ok, null},
+                   msgpack:unpack(msgpack:pack(nil), [{format,jsx}])),
+     ?_assertEqual({ok, nil},
+                   msgpack:unpack(msgpack:pack(null, [{format,jsx}]))),
+     ?_assertEqual({ok, <<"null">>},
+                   msgpack:unpack(msgpack:pack(null, [{allow_atom,pack}]))),
+     ?_assertEqual({ok, <<"nil">>},
+                   msgpack:unpack(msgpack:pack(nil,
+                                               [{format,jsx},{allow_atom,pack}])))].
+
 string_test() ->
     {ok, CWD} = file:get_cwd(),
     Path = CWD ++ "/../test/utf8.txt",