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%% @author Bob Ippolito <bob@mochimedia.com>
%% @copyright 2007 Mochi Media, Inc.
%%
%% Permission is hereby granted, free of charge, to any person obtaining a
%% copy of this software and associated documentation files (the "Software"),
%% to deal in the Software without restriction, including without limitation
%% the rights to use, copy, modify, merge, publish, distribute, sublicense,
%% and/or sell copies of the Software, and to permit persons to whom the
%% Software is furnished to do so, subject to the following conditions:
%%
%% The above copyright notice and this permission notice shall be included in
%% all copies or substantial portions of the Software.
%%
%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
%% THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
%% FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
%% DEALINGS IN THE SOFTWARE.
%% @doc Yet another JSON (RFC 4627) library for Erlang. mochijson2 works
%% with binaries as strings, arrays as lists (without an {array, _})
%% wrapper and it only knows how to decode UTF-8 (and ASCII).
%%
%% JSON terms are decoded as follows (javascript -> erlang):
%% <ul>
%% <li>{"key": "value"} ->
%% {struct, [{<<"key">>, <<"value">>}]}</li>
%% <li>["array", 123, 12.34, true, false, null] ->
%% [<<"array">>, 123, 12.34, true, false, null]
%% </li>
%% </ul>
%% <ul>
%% <li>Strings in JSON decode to UTF-8 binaries in Erlang</li>
%% <li>Objects decode to {struct, PropList}</li>
%% <li>Numbers decode to integer or float</li>
%% <li>true, false, null decode to their respective terms.</li>
%% </ul>
%% The encoder will accept the same format that the decoder will produce,
%% but will also allow additional cases for leniency:
%% <ul>
%% <li>atoms other than true, false, null will be considered UTF-8
%% strings (even as a proplist key)
%% </li>
%% <li>{json, IoList} will insert IoList directly into the output
%% with no validation
%% </li>
%% <li>{array, Array} will be encoded as Array
%% (legacy mochijson style)
%% </li>
%% <li>A non-empty raw proplist will be encoded as an object as long
%% as the first pair does not have an atom key of json, struct,
%% or array
%% </li>
%% </ul>
-module(mochijson2).
-author('bob@mochimedia.com').
-export([encoder/1, encode/1]).
-export([decoder/1, decode/1, decode/2]).
%% This is a macro to placate syntax highlighters..
-define(Q, $\").
-define(ADV_COL(S, N), S#decoder{offset=N+S#decoder.offset,
column=N+S#decoder.column}).
-define(INC_COL(S), S#decoder{offset=1+S#decoder.offset,
column=1+S#decoder.column}).
-define(INC_LINE(S), S#decoder{offset=1+S#decoder.offset,
column=1,
line=1+S#decoder.line}).
-define(INC_CHAR(S, C),
case C of
$\n ->
S#decoder{column=1,
line=1+S#decoder.line,
offset=1+S#decoder.offset};
_ ->
S#decoder{column=1+S#decoder.column,
offset=1+S#decoder.offset}
end).
-define(IS_WHITESPACE(C),
(C =:= $\s orelse C =:= $\t orelse C =:= $\r orelse C =:= $\n)).
-ifdef(map_unavailable).
-define(IS_MAP(_), false).
-else.
-define(IS_MAP(X), is_map(X)).
-endif.
%% @type json_string() = atom | binary()
%% @type json_number() = integer() | float()
%% @type json_array() = [json_term()]
%% @type json_object() = {struct, [{json_string(), json_term()}]}
%% @type json_eep18_object() = {[{json_string(), json_term()}]}
%% @type json_iolist() = {json, iolist()}
%% @type json_term() = json_string() | json_number() | json_array() |
%% json_object() | json_eep18_object() | json_iolist()
-record(encoder, {handler=null,
utf8=false}).
-record(decoder, {object_hook=null,
offset=0,
line=1,
column=1,
state=null}).
%% @spec encoder([encoder_option()]) -> function()
%% @doc Create an encoder/1 with the given options.
%% @type encoder_option() = handler_option() | utf8_option()
%% @type utf8_option() = boolean(). Emit unicode as utf8 (default - false)
encoder(Options) ->
State = parse_encoder_options(Options, #encoder{}),
fun (O) -> json_encode(O, State) end.
%% @spec encode(json_term()) -> iolist()
%% @doc Encode the given as JSON to an iolist.
encode(Any) ->
json_encode(Any, #encoder{}).
%% @spec decoder([decoder_option()]) -> function()
%% @doc Create a decoder/1 with the given options.
decoder(Options) ->
State = parse_decoder_options(Options, #decoder{}),
fun (O) -> json_decode(O, State) end.
%% @spec decode(iolist(), [{format, proplist | eep18 | struct | map}]) -> json_term()
%% @doc Decode the given iolist to Erlang terms using the given object format
%% for decoding, where proplist returns JSON objects as [{binary(), json_term()}]
%% proplists, eep18 returns JSON objects as {[binary(), json_term()]},
%% map returns JSON objects as #{binary() => json_term()}, and struct
%% returns them as-is.
decode(S, Options) ->
json_decode(S, parse_decoder_options(Options, #decoder{})).
%% @spec decode(iolist()) -> json_term()
%% @doc Decode the given iolist to Erlang terms.
decode(S) ->
json_decode(S, #decoder{}).
%% Internal API
parse_encoder_options([], State) ->
State;
parse_encoder_options([{handler, Handler} | Rest], State) ->
parse_encoder_options(Rest, State#encoder{handler=Handler});
parse_encoder_options([{utf8, Switch} | Rest], State) ->
parse_encoder_options(Rest, State#encoder{utf8=Switch}).
parse_decoder_options([], State) ->
State;
parse_decoder_options([{object_hook, Hook} | Rest], State) ->
parse_decoder_options(Rest, State#decoder{object_hook=Hook});
parse_decoder_options([{format, map} | Rest], State) ->
Hook = make_object_hook_for_map(),
parse_decoder_options(Rest, State#decoder{object_hook=Hook});
parse_decoder_options([{format, Format} | Rest], State)
when Format =:= struct orelse Format =:= eep18 orelse Format =:= proplist ->
parse_decoder_options(Rest, State#decoder{object_hook=Format}).
-ifdef(map_unavailable).
make_object_hook_for_map() ->
exit({json_decode, {bad_format, map_unavailable}}).
-else.
make_object_hook_for_map() ->
fun ({struct, P}) -> maps:from_list(P) end.
-endif.
json_encode(true, _State) ->
<<"true">>;
json_encode(false, _State) ->
<<"false">>;
json_encode(null, _State) ->
<<"null">>;
json_encode(I, _State) when is_integer(I) ->
integer_to_list(I);
json_encode(F, _State) when is_float(F) ->
mochinum:digits(F);
json_encode(S, State) when is_binary(S); is_atom(S) ->
json_encode_string(S, State);
json_encode([{K, _}|_] = Props, State) when (K =/= struct andalso
K =/= array andalso
K =/= json) ->
json_encode_proplist(Props, State);
json_encode({struct, Props}, State) when is_list(Props) ->
json_encode_proplist(Props, State);
json_encode({Props}, State) when is_list(Props) ->
json_encode_proplist(Props, State);
json_encode({}, State) ->
json_encode_proplist([], State);
json_encode(Array, State) when is_list(Array) ->
json_encode_array(Array, State);
json_encode({array, Array}, State) when is_list(Array) ->
json_encode_array(Array, State);
json_encode(M, State) when ?IS_MAP(M) ->
json_encode_map(M, State);
json_encode({json, IoList}, _State) ->
IoList;
json_encode(Bad, #encoder{handler=null}) ->
exit({json_encode, {bad_term, Bad}});
json_encode(Bad, State=#encoder{handler=Handler}) ->
json_encode(Handler(Bad), State).
json_encode_array([], _State) ->
<<"[]">>;
json_encode_array(L, State) ->
F = fun (O, Acc) ->
[$,, json_encode(O, State) | Acc]
end,
[$, | Acc1] = lists:foldl(F, "[", L),
lists:reverse([$\] | Acc1]).
json_encode_proplist([], _State) ->
<<"{}">>;
json_encode_proplist(Props, State) ->
F = fun ({K, V}, Acc) ->
KS = json_encode_string(K, State),
VS = json_encode(V, State),
[$,, VS, $:, KS | Acc]
end,
[$, | Acc1] = lists:foldl(F, "{", Props),
lists:reverse([$\} | Acc1]).
-ifdef(map_unavailable).
json_encode_map(Bad, _State) ->
%% IS_MAP definition guarantees that this branch is dead
exit({json_encode, {bad_term, Bad}}).
-else.
json_encode_map(Map, _State) when map_size(Map) =:= 0 ->
<<"{}">>;
json_encode_map(Map, State) ->
F = fun(K, V, Acc) ->
KS = json_encode_string(K, State),
VS = json_encode(V, State),
[$,, VS, $:, KS | Acc]
end,
[$, | Acc1] = maps:fold(F, "{", Map),
lists:reverse([$\} | Acc1]).
-endif.
json_encode_string(A, State) when is_atom(A) ->
json_encode_string(atom_to_binary(A, latin1), State);
json_encode_string(B, State) when is_binary(B) ->
case json_bin_is_safe(B) of
true ->
[?Q, B, ?Q];
false ->
json_encode_string_unicode(unicode:characters_to_list(B), State, [?Q])
end;
json_encode_string(I, _State) when is_integer(I) ->
[?Q, integer_to_list(I), ?Q];
json_encode_string(L, State) when is_list(L) ->
case json_string_is_safe(L) of
true ->
[?Q, L, ?Q];
false ->
json_encode_string_unicode(L, State, [?Q])
end.
json_string_is_safe([]) ->
true;
json_string_is_safe([C | Rest]) ->
case C of
?Q ->
false;
$\\ ->
false;
$\b ->
false;
$\f ->
false;
$\n ->
false;
$\r ->
false;
$\t ->
false;
C when C >= 0, C < $\s; C >= 16#7f, C =< 16#10FFFF ->
false;
C when C < 16#7f ->
json_string_is_safe(Rest);
_ ->
exit({json_encode, {bad_char, C}})
end.
json_bin_is_safe(<<>>) ->
true;
json_bin_is_safe(<<C, Rest/binary>>) ->
case C of
?Q ->
false;
$\\ ->
false;
$\b ->
false;
$\f ->
false;
$\n ->
false;
$\r ->
false;
$\t ->
false;
C when C >= 0, C < $\s; C >= 16#7f ->
false;
C when C < 16#7f ->
json_bin_is_safe(Rest)
end.
json_encode_string_unicode([], _State, Acc) ->
lists:reverse([$\" | Acc]);
json_encode_string_unicode([C | Cs], State, Acc) ->
Acc1 = case C of
?Q ->
[?Q, $\\ | Acc];
%% Escaping solidus is only useful when trying to protect
%% against "</script>" injection attacks which are only
%% possible when JSON is inserted into a HTML document
%% in-line. mochijson2 does not protect you from this, so
%% if you do insert directly into HTML then you need to
%% uncomment the following case or escape the output of encode.
%%
%% $/ ->
%% [$/, $\\ | Acc];
%%
$\\ ->
[$\\, $\\ | Acc];
$\b ->
[$b, $\\ | Acc];
$\f ->
[$f, $\\ | Acc];
$\n ->
[$n, $\\ | Acc];
$\r ->
[$r, $\\ | Acc];
$\t ->
[$t, $\\ | Acc];
C when C >= 0, C < $\s ->
[unihex(C) | Acc];
C when C >= 16#7f, C =< 16#10FFFF, State#encoder.utf8 ->
[unicode:characters_to_binary([C]) | Acc];
C when C >= 16#7f, C =< 16#10FFFF, not State#encoder.utf8 ->
[unihex(C) | Acc];
C when C < 16#7f ->
[C | Acc];
_ ->
%% json_string_is_safe guarantees that this branch is dead
exit({json_encode, {bad_char, C}})
end,
json_encode_string_unicode(Cs, State, Acc1).
hexdigit(C) when C >= 0, C =< 9 ->
C + $0;
hexdigit(C) when C =< 15 ->
C + $a - 10.
unihex(C) when C < 16#10000 ->
<<D3:4, D2:4, D1:4, D0:4>> = <<C:16>>,
Digits = [hexdigit(D) || D <- [D3, D2, D1, D0]],
[$\\, $u | Digits];
unihex(C) when C =< 16#10FFFF ->
N = C - 16#10000,
S1 = 16#d800 bor ((N bsr 10) band 16#3ff),
S2 = 16#dc00 bor (N band 16#3ff),
[unihex(S1), unihex(S2)].
json_decode(L, S) when is_list(L) ->
json_decode(iolist_to_binary(L), S);
json_decode(B, S) ->
{Res, S1} = decode1(B, S),
{eof, _} = tokenize(B, S1#decoder{state=trim}),
Res.
decode1(B, S=#decoder{state=null}) ->
case tokenize(B, S#decoder{state=any}) of
{{const, C}, S1} ->
{C, S1};
{start_array, S1} ->
decode_array(B, S1);
{start_object, S1} ->
decode_object(B, S1)
end.
make_object(V, #decoder{object_hook=N}) when N =:= null orelse N =:= struct ->
V;
make_object({struct, P}, #decoder{object_hook=eep18}) ->
{P};
make_object({struct, P}, #decoder{object_hook=proplist}) ->
P;
make_object(V, #decoder{object_hook=Hook}) ->
Hook(V).
decode_object(B, S) ->
decode_object(B, S#decoder{state=key}, []).
decode_object(B, S=#decoder{state=key}, Acc) ->
case tokenize(B, S) of
{end_object, S1} ->
V = make_object({struct, lists:reverse(Acc)}, S1),
{V, S1#decoder{state=null}};
{{const, K}, S1} ->
{colon, S2} = tokenize(B, S1),
{V, S3} = decode1(B, S2#decoder{state=null}),
decode_object(B, S3#decoder{state=comma}, [{K, V} | Acc])
end;
decode_object(B, S=#decoder{state=comma}, Acc) ->
case tokenize(B, S) of
{end_object, S1} ->
V = make_object({struct, lists:reverse(Acc)}, S1),
{V, S1#decoder{state=null}};
{comma, S1} ->
decode_object(B, S1#decoder{state=key}, Acc)
end.
decode_array(B, S) ->
decode_array(B, S#decoder{state=any}, []).
decode_array(B, S=#decoder{state=any}, Acc) ->
case tokenize(B, S) of
{end_array, S1} ->
{lists:reverse(Acc), S1#decoder{state=null}};
{start_array, S1} ->
{Array, S2} = decode_array(B, S1),
decode_array(B, S2#decoder{state=comma}, [Array | Acc]);
{start_object, S1} ->
{Array, S2} = decode_object(B, S1),
decode_array(B, S2#decoder{state=comma}, [Array | Acc]);
{{const, Const}, S1} ->
decode_array(B, S1#decoder{state=comma}, [Const | Acc])
end;
decode_array(B, S=#decoder{state=comma}, Acc) ->
case tokenize(B, S) of
{end_array, S1} ->
{lists:reverse(Acc), S1#decoder{state=null}};
{comma, S1} ->
decode_array(B, S1#decoder{state=any}, Acc)
end.
tokenize_string(B, S=#decoder{offset=O}) ->
case tokenize_string_fast(B, O) of
{escape, O1} ->
Length = O1 - O,
S1 = ?ADV_COL(S, Length),
<<_:O/binary, Head:Length/binary, _/binary>> = B,
tokenize_string(B, S1, lists:reverse(binary_to_list(Head)));
O1 ->
Length = O1 - O,
<<_:O/binary, String:Length/binary, ?Q, _/binary>> = B,
{{const, String}, ?ADV_COL(S, Length + 1)}
end.
tokenize_string_fast(B, O) ->
case B of
<<_:O/binary, ?Q, _/binary>> ->
O;
<<_:O/binary, $\\, _/binary>> ->
{escape, O};
<<_:O/binary, C1, _/binary>> when C1 < 128 ->
tokenize_string_fast(B, 1 + O);
<<_:O/binary, C1, C2, _/binary>> when C1 >= 194, C1 =< 223,
C2 >= 128, C2 =< 191 ->
tokenize_string_fast(B, 2 + O);
<<_:O/binary, C1, C2, C3, _/binary>> when C1 >= 224, C1 =< 239,
C2 >= 128, C2 =< 191,
C3 >= 128, C3 =< 191 ->
tokenize_string_fast(B, 3 + O);
<<_:O/binary, C1, C2, C3, C4, _/binary>> when C1 >= 240, C1 =< 244,
C2 >= 128, C2 =< 191,
C3 >= 128, C3 =< 191,
C4 >= 128, C4 =< 191 ->
tokenize_string_fast(B, 4 + O);
_ ->
throw(invalid_utf8)
end.
tokenize_string(B, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary, ?Q, _/binary>> ->
{{const, iolist_to_binary(lists:reverse(Acc))}, ?INC_COL(S)};
<<_:O/binary, "\\\"", _/binary>> ->
tokenize_string(B, ?ADV_COL(S, 2), [$\" | Acc]);
<<_:O/binary, "\\\\", _/binary>> ->
tokenize_string(B, ?ADV_COL(S, 2), [$\\ | Acc]);
<<_:O/binary, "\\/", _/binary>> ->
tokenize_string(B, ?ADV_COL(S, 2), [$/ | Acc]);
<<_:O/binary, "\\b", _/binary>> ->
tokenize_string(B, ?ADV_COL(S, 2), [$\b | Acc]);
<<_:O/binary, "\\f", _/binary>> ->
tokenize_string(B, ?ADV_COL(S, 2), [$\f | Acc]);
<<_:O/binary, "\\n", _/binary>> ->
tokenize_string(B, ?ADV_COL(S, 2), [$\n | Acc]);
<<_:O/binary, "\\r", _/binary>> ->
tokenize_string(B, ?ADV_COL(S, 2), [$\r | Acc]);
<<_:O/binary, "\\t", _/binary>> ->
tokenize_string(B, ?ADV_COL(S, 2), [$\t | Acc]);
<<_:O/binary, "\\u", C3, C2, C1, C0, Rest/binary>> ->
C = erlang:list_to_integer([C3, C2, C1, C0], 16),
if C > 16#D7FF, C < 16#DC00 ->
%% coalesce UTF-16 surrogate pair
<<"\\u", D3, D2, D1, D0, _/binary>> = Rest,
D = erlang:list_to_integer([D3,D2,D1,D0], 16),
Acc1 = [unicode:characters_to_binary(
<<C:16/big-unsigned-integer,
D:16/big-unsigned-integer>>,
utf16)
| Acc],
tokenize_string(B, ?ADV_COL(S, 12), Acc1);
true ->
Acc1 = [unicode:characters_to_binary([C]) | Acc],
tokenize_string(B, ?ADV_COL(S, 6), Acc1)
end;
<<_:O/binary, C1, _/binary>> when C1 < 128 ->
tokenize_string(B, ?INC_CHAR(S, C1), [C1 | Acc]);
<<_:O/binary, C1, C2, _/binary>> when C1 >= 194, C1 =< 223,
C2 >= 128, C2 =< 191 ->
tokenize_string(B, ?ADV_COL(S, 2), [C2, C1 | Acc]);
<<_:O/binary, C1, C2, C3, _/binary>> when C1 >= 224, C1 =< 239,
C2 >= 128, C2 =< 191,
C3 >= 128, C3 =< 191 ->
tokenize_string(B, ?ADV_COL(S, 3), [C3, C2, C1 | Acc]);
<<_:O/binary, C1, C2, C3, C4, _/binary>> when C1 >= 240, C1 =< 244,
C2 >= 128, C2 =< 191,
C3 >= 128, C3 =< 191,
C4 >= 128, C4 =< 191 ->
tokenize_string(B, ?ADV_COL(S, 4), [C4, C3, C2, C1 | Acc]);
_ ->
throw(invalid_utf8)
end.
tokenize_number(B, S) ->
case tokenize_number(B, sign, S, []) of
{{int, Int}, S1} ->
{{const, list_to_integer(Int)}, S1};
{{float, Float}, S1} ->
{{const, list_to_float(Float)}, S1}
end.
tokenize_number(B, sign, S=#decoder{offset=O}, []) ->
case B of
<<_:O/binary, $-, _/binary>> ->
tokenize_number(B, int, ?INC_COL(S), [$-]);
_ ->
tokenize_number(B, int, S, [])
end;
tokenize_number(B, int, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary, $0, _/binary>> ->
tokenize_number(B, frac, ?INC_COL(S), [$0 | Acc]);
<<_:O/binary, C, _/binary>> when C >= $1 andalso C =< $9 ->
tokenize_number(B, int1, ?INC_COL(S), [C | Acc])
end;
tokenize_number(B, int1, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary, C, _/binary>> when C >= $0 andalso C =< $9 ->
tokenize_number(B, int1, ?INC_COL(S), [C | Acc]);
_ ->
tokenize_number(B, frac, S, Acc)
end;
tokenize_number(B, frac, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary, $., C, _/binary>> when C >= $0, C =< $9 ->
tokenize_number(B, frac1, ?ADV_COL(S, 2), [C, $. | Acc]);
<<_:O/binary, E, _/binary>> when E =:= $e orelse E =:= $E ->
tokenize_number(B, esign, ?INC_COL(S), [$e, $0, $. | Acc]);
_ ->
{{int, lists:reverse(Acc)}, S}
end;
tokenize_number(B, frac1, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary, C, _/binary>> when C >= $0 andalso C =< $9 ->
tokenize_number(B, frac1, ?INC_COL(S), [C | Acc]);
<<_:O/binary, E, _/binary>> when E =:= $e orelse E =:= $E ->
tokenize_number(B, esign, ?INC_COL(S), [$e | Acc]);
_ ->
{{float, lists:reverse(Acc)}, S}
end;
tokenize_number(B, esign, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary, C, _/binary>> when C =:= $- orelse C=:= $+ ->
tokenize_number(B, eint, ?INC_COL(S), [C | Acc]);
_ ->
tokenize_number(B, eint, S, Acc)
end;
tokenize_number(B, eint, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary, C, _/binary>> when C >= $0 andalso C =< $9 ->
tokenize_number(B, eint1, ?INC_COL(S), [C | Acc])
end;
tokenize_number(B, eint1, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary, C, _/binary>> when C >= $0 andalso C =< $9 ->
tokenize_number(B, eint1, ?INC_COL(S), [C | Acc]);
_ ->
{{float, lists:reverse(Acc)}, S}
end.
tokenize(B, S=#decoder{offset=O}) ->
case B of
<<_:O/binary, C, _/binary>> when ?IS_WHITESPACE(C) ->
tokenize(B, ?INC_CHAR(S, C));
<<_:O/binary, "{", _/binary>> ->
{start_object, ?INC_COL(S)};
<<_:O/binary, "}", _/binary>> ->
{end_object, ?INC_COL(S)};
<<_:O/binary, "[", _/binary>> ->
{start_array, ?INC_COL(S)};
<<_:O/binary, "]", _/binary>> ->
{end_array, ?INC_COL(S)};
<<_:O/binary, ",", _/binary>> ->
{comma, ?INC_COL(S)};
<<_:O/binary, ":", _/binary>> ->
{colon, ?INC_COL(S)};
<<_:O/binary, "null", _/binary>> ->
{{const, null}, ?ADV_COL(S, 4)};
<<_:O/binary, "true", _/binary>> ->
{{const, true}, ?ADV_COL(S, 4)};
<<_:O/binary, "false", _/binary>> ->
{{const, false}, ?ADV_COL(S, 5)};
<<_:O/binary, "\"", _/binary>> ->
tokenize_string(B, ?INC_COL(S));
<<_:O/binary, C, _/binary>> when (C >= $0 andalso C =< $9)
orelse C =:= $- ->
tokenize_number(B, S);
<<_:O/binary>> ->
trim = S#decoder.state,
{eof, S}
end.
%%
%% Tests
%%
-ifdef(TEST).
-include_lib("eunit/include/eunit.hrl").
%% testing constructs borrowed from the Yaws JSON implementation.
%% Create an object from a list of Key/Value pairs.
obj_new() ->
{struct, []}.
is_obj({struct, Props}) ->
F = fun ({K, _}) when is_binary(K) -> true end,
lists:all(F, Props).
obj_from_list(Props) ->
Obj = {struct, Props},
?assert(is_obj(Obj)),
Obj.
%% Test for equivalence of Erlang terms.
%% Due to arbitrary order of construction, equivalent objects might
%% compare unequal as erlang terms, so we need to carefully recurse
%% through aggregates (tuples and objects).
equiv({struct, Props1}, {struct, Props2}) ->
equiv_object(Props1, Props2);
equiv(L1, L2) when is_list(L1), is_list(L2) ->
equiv_list(L1, L2);
equiv(N1, N2) when is_number(N1), is_number(N2) -> N1 == N2;
equiv(B1, B2) when is_binary(B1), is_binary(B2) -> B1 == B2;
equiv(A, A) when A =:= true orelse A =:= false orelse A =:= null -> true.
%% Object representation and traversal order is unknown.
%% Use the sledgehammer and sort property lists.
equiv_object(Props1, Props2) ->
L1 = lists:keysort(1, Props1),
L2 = lists:keysort(1, Props2),
Pairs = lists:zip(L1, L2),
true = lists:all(fun({{K1, V1}, {K2, V2}}) ->
equiv(K1, K2) and equiv(V1, V2)
end, Pairs).
%% Recursively compare tuple elements for equivalence.
equiv_list([], []) ->
true;
equiv_list([V1 | L1], [V2 | L2]) ->
equiv(V1, V2) andalso equiv_list(L1, L2).
decode_test() ->
[1199344435545.0, 1] = decode(<<"[1199344435545.0,1]">>),
<<16#F0,16#9D,16#9C,16#95>> = decode([34,"\\ud835","\\udf15",34]).
e2j_vec_test() ->
test_one(e2j_test_vec(utf8), 1).
test_one([], _N) ->
%% io:format("~p tests passed~n", [N-1]),
ok;
test_one([{E, J} | Rest], N) ->
%% io:format("[~p] ~p ~p~n", [N, E, J]),
true = equiv(E, decode(J)),
true = equiv(E, decode(encode(E))),
test_one(Rest, 1+N).
e2j_test_vec(utf8) ->
[
{1, "1"},
{3.1416, "3.14160"}, %% text representation may truncate, trail zeroes
{-1, "-1"},
{-3.1416, "-3.14160"},
{12.0e10, "1.20000e+11"},
{1.234E+10, "1.23400e+10"},
{-1.234E-10, "-1.23400e-10"},
{10.0, "1.0e+01"},
{123.456, "1.23456E+2"},
{10.0, "1e1"},
{<<"foo">>, "\"foo\""},
{<<"foo", 5, "bar">>, "\"foo\\u0005bar\""},
{<<"">>, "\"\""},
{<<"\n\n\n">>, "\"\\n\\n\\n\""},
{<<"\" \b\f\r\n\t\"">>, "\"\\\" \\b\\f\\r\\n\\t\\\"\""},
{obj_new(), "{}"},
{obj_from_list([{<<"foo">>, <<"bar">>}]), "{\"foo\":\"bar\"}"},
{obj_from_list([{<<"foo">>, <<"bar">>}, {<<"baz">>, 123}]),
"{\"foo\":\"bar\",\"baz\":123}"},
{[], "[]"},
{[[]], "[[]]"},
{[1, <<"foo">>], "[1,\"foo\"]"},
%% json array in a json object
{obj_from_list([{<<"foo">>, [123]}]),
"{\"foo\":[123]}"},
%% json object in a json object
{obj_from_list([{<<"foo">>, obj_from_list([{<<"bar">>, true}])}]),
"{\"foo\":{\"bar\":true}}"},
%% fold evaluation order
{obj_from_list([{<<"foo">>, []},
{<<"bar">>, obj_from_list([{<<"baz">>, true}])},
{<<"alice">>, <<"bob">>}]),
"{\"foo\":[],\"bar\":{\"baz\":true},\"alice\":\"bob\"}"},
%% json object in a json array
{[-123, <<"foo">>, obj_from_list([{<<"bar">>, []}]), null],
"[-123,\"foo\",{\"bar\":[]},null]"}
].
%% test utf8 encoding
encoder_utf8_test() ->
%% safe conversion case (default)
<<"\"\\u0001\\u0442\\u0435\\u0441\\u0442\"">> =
iolist_to_binary(encode(<<1,"\321\202\320\265\321\201\321\202">>)),
%% raw utf8 output (optional)
Enc = mochijson2:encoder([{utf8, true}]),
<<34,"\\u0001",209,130,208,181,209,129,209,130,34>> =
iolist_to_binary(Enc(<<1,"\321\202\320\265\321\201\321\202">>)).
input_validation_test() ->
Good = [
{16#00A3, <<?Q, 16#C2, 16#A3, ?Q>>}, %% pound
{16#20AC, <<?Q, 16#E2, 16#82, 16#AC, ?Q>>}, %% euro
{16#10196, <<?Q, 16#F0, 16#90, 16#86, 16#96, ?Q>>} %% denarius
],
lists:foreach(fun({CodePoint, UTF8}) ->
Expect = unicode:characters_to_binary([CodePoint]),
Expect = decode(UTF8)
end, Good),
Bad = [
%% 2nd, 3rd, or 4th byte of a multi-byte sequence w/o leading byte
<<?Q, 16#80, ?Q>>,
%% missing continuations, last byte in each should be 80-BF
<<?Q, 16#C2, 16#7F, ?Q>>,
<<?Q, 16#E0, 16#80,16#7F, ?Q>>,
<<?Q, 16#F0, 16#80, 16#80, 16#7F, ?Q>>,
%% we don't support code points > 10FFFF per RFC 3629
<<?Q, 16#F5, 16#80, 16#80, 16#80, ?Q>>,
%% escape characters trigger a different code path
<<?Q, $\\, $\n, 16#80, ?Q>>
],
lists:foreach(
fun(X) ->
ok = try decode(X) catch invalid_utf8 -> ok end,
%% could be {ucs,{bad_utf8_character_code}} or
%% {json_encode,{bad_char,_}}
{'EXIT', _} = (catch encode(X))
end, Bad).
inline_json_test() ->
?assertEqual(<<"\"iodata iodata\"">>,
iolist_to_binary(
encode({json, [<<"\"iodata">>, " iodata\""]}))),
?assertEqual({struct, [{<<"key">>, <<"iodata iodata">>}]},
decode(
encode({struct,
[{key, {json, [<<"\"iodata">>, " iodata\""]}}]}))),
ok.
big_unicode_test() ->
UTF8Seq = unicode:characters_to_binary([16#0001d120]),
?assertEqual(
<<"\"\\ud834\\udd20\"">>,
iolist_to_binary(encode(UTF8Seq))),
?assertEqual(
UTF8Seq,
decode(iolist_to_binary(encode(UTF8Seq)))),
ok.
custom_decoder_test() ->
?assertEqual(
{struct, [{<<"key">>, <<"value">>}]},
(decoder([]))("{\"key\": \"value\"}")),
F = fun ({struct, [{<<"key">>, <<"value">>}]}) -> win end,
?assertEqual(
win,
(decoder([{object_hook, F}]))("{\"key\": \"value\"}")),
ok.
atom_test() ->
%% JSON native atoms
[begin
?assertEqual(A, decode(atom_to_list(A))),
?assertEqual(iolist_to_binary(atom_to_list(A)),
iolist_to_binary(encode(A)))
end || A <- [true, false, null]],
%% Atom to string
?assertEqual(
<<"\"foo\"">>,
iolist_to_binary(encode(foo))),
?assertEqual(
<<"\"\\ud834\\udd20\"">>,
iolist_to_binary(
encode(
binary_to_atom(
unicode:characters_to_binary([16#0001d120]), latin1)))),
ok.
key_encode_test() ->
%% Some forms are accepted as keys that would not be strings in other
%% cases
?assertEqual(
<<"{\"foo\":1}">>,
iolist_to_binary(encode({struct, [{foo, 1}]}))),
?assertEqual(
<<"{\"foo\":1}">>,
iolist_to_binary(encode({struct, [{<<"foo">>, 1}]}))),
?assertEqual(
<<"{\"foo\":1}">>,
iolist_to_binary(encode({struct, [{"foo", 1}]}))),
?assertEqual(
<<"{\"foo\":1}">>,
iolist_to_binary(encode([{foo, 1}]))),
?assertEqual(
<<"{\"foo\":1}">>,
iolist_to_binary(encode([{<<"foo">>, 1}]))),
?assertEqual(
<<"{\"foo\":1}">>,
iolist_to_binary(encode([{"foo", 1}]))),
?assertEqual(
<<"{\"\\ud834\\udd20\":1}">>,
iolist_to_binary(
encode({struct, [{[16#0001d120], 1}]}))),
?assertEqual(
<<"{\"1\":1}">>,
iolist_to_binary(encode({struct, [{1, 1}]}))),
ok.
unsafe_chars_test() ->
Chars = "\"\\\b\f\n\r\t",
[begin
?assertEqual(false, json_string_is_safe([C])),
?assertEqual(false, json_bin_is_safe(<<C>>)),
?assertEqual(<<C>>, decode(encode(<<C>>)))
end || C <- Chars],
?assertEqual(
false,
json_string_is_safe([16#0001d120])),
?assertEqual(
false,
json_bin_is_safe(unicode:characters_to_binary([16#0001d120]))),
?assertEqual(
[16#0001d120],
unicode:characters_to_list(
decode(
encode(
binary_to_atom(
unicode:characters_to_binary([16#0001d120]),
latin1))))),
?assertEqual(
false,
json_string_is_safe([16#10ffff])),
?assertEqual(
false,
json_bin_is_safe(unicode:characters_to_binary([16#10ffff]))),
%% solidus can be escaped but isn't unsafe by default
?assertEqual(
<<"/">>,
decode(<<"\"\\/\"">>)),
ok.
int_test() ->
?assertEqual(0, decode("0")),
?assertEqual(1, decode("1")),
?assertEqual(11, decode("11")),
ok.
large_int_test() ->
?assertEqual(<<"-2147483649214748364921474836492147483649">>,
iolist_to_binary(encode(-2147483649214748364921474836492147483649))),
?assertEqual(<<"2147483649214748364921474836492147483649">>,
iolist_to_binary(encode(2147483649214748364921474836492147483649))),
ok.
float_test() ->
?assertEqual(<<"-2147483649.0">>, iolist_to_binary(encode(-2147483649.0))),
?assertEqual(<<"2147483648.0">>, iolist_to_binary(encode(2147483648.0))),
ok.
handler_test() ->
?assertEqual(
{'EXIT',{json_encode,{bad_term,{x,y}}}},
catch encode({x,y})),
F = fun ({x,y}) -> [] end,
?assertEqual(
<<"[]">>,
iolist_to_binary((encoder([{handler, F}]))({x, y}))),
ok.
encode_empty_test_() ->
[{A, ?_assertEqual(<<"{}">>, iolist_to_binary(encode(B)))}
|| {A, B} <- [{"eep18 {}", {}},
{"eep18 {[]}", {[]}},
{"{struct, []}", {struct, []}}]].
encode_test_() ->
P = [{<<"k">>, <<"v">>}],
JSON = iolist_to_binary(encode({struct, P})),
[{atom_to_list(F),
?_assertEqual(JSON, iolist_to_binary(encode(decode(JSON, [{format, F}]))))}
|| F <- [struct, eep18, proplist]].
format_test_() ->
P = [{<<"k">>, <<"v">>}],
JSON = iolist_to_binary(encode({struct, P})),
[{atom_to_list(F),
?_assertEqual(A, decode(JSON, [{format, F}]))}
|| {F, A} <- [{struct, {struct, P}},
{eep18, {P}},
{proplist, P}]].
array_test() ->
A = [<<"hello">>],
?assertEqual(A, decode(encode({array, A}))).
bad_char_test() ->
?assertEqual(
{'EXIT', {json_encode, {bad_char, 16#110000}}},
catch json_string_is_safe([16#110000])).
utf8_roundtrip_test_() ->
%% These are the boundary cases for UTF8 encoding
Codepoints = [%% 7 bits -> 1 byte
16#00, 16#7f,
%% 11 bits -> 2 bytes
16#080, 16#07ff,
%% 16 bits -> 3 bytes
16#0800, 16#ffff,
16#d7ff, 16#e000,
%% 21 bits -> 4 bytes
16#010000, 16#10ffff],
UTF8 = unicode:characters_to_binary(Codepoints),
Encode = encoder([{utf8, true}]),
[{"roundtrip escaped",
?_assertEqual(UTF8, decode(encode(UTF8)))},
{"roundtrip utf8",
?_assertEqual(UTF8, decode(Encode(UTF8)))}].
utf8_non_character_test_() ->
S = unicode:characters_to_binary([16#ffff, 16#fffe]),
[{"roundtrip escaped", ?_assertEqual(S, decode(encode(S)))},
{"roundtrip utf8", ?_assertEqual(S, decode((encoder([{utf8, true}]))(S)))}].
-ifndef(map_unavailable).
decode_map_test() ->
Json = "{\"var1\": 3, \"var2\": {\"var3\": 7}}",
M = #{<<"var1">> => 3,<<"var2">> => #{<<"var3">> => 7}},
?assertEqual(M, decode(Json, [{format, map}])).
encode_map_test() ->
M = <<"{\"a\":1,\"b\":{\"c\":2}}">>,
?assertEqual(M, iolist_to_binary(encode(#{a => 1, b => #{ c => 2}}))).
encode_empty_map_test() ->
?assertEqual(<<"{}">>, encode(#{})).
-endif.
-endif.