From ae13b934c6bc5d7bbedfcae47fa6018bace3089a Mon Sep 17 00:00:00 2001
From: alisdair sullivan <alisdairsullivan@yahoo.ca>
Date: Wed, 4 Apr 2012 20:13:27 -0700
Subject: [PATCH] add {pre_encoder, F} variant of {pre_encoders, [F, G,...]}

---
 src/jsx_encoder.erl | 8 ++++----
 src/jsx_utils.erl   | 4 ++++
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/jsx_encoder.erl b/src/jsx_encoder.erl
index 7bf2b3c..cd2a08c 100644
--- a/src/jsx_encoder.erl
+++ b/src/jsx_encoder.erl
@@ -812,7 +812,7 @@ pre_encoders_test_() ->
             ]
         )},
         {"replace lists with empty lists", ?_assertEqual(
-            encode(Term, [{pre_encoders, [fun(V) -> case V of [{_,_}|_] -> V; [{}] -> V; V when is_list(V) -> []; _ -> V end end]}]),
+            encode(Term, [{pre_encoder, fun(V) -> case V of [{_,_}|_] -> V; [{}] -> V; V when is_list(V) -> []; _ -> V end end}]),
             [
                 start_object,
                     {key, <<"object">>}, start_object,
@@ -825,7 +825,7 @@ pre_encoders_test_() ->
             ]
         )},
         {"replace objects with empty objects", ?_assertEqual(
-            encode(Term, [{pre_encoders, [fun(V) -> case V of [{_,_}|_] -> [{}]; _ -> V end end]}]),
+            encode(Term, [{pre_encoder, fun(V) -> case V of [{_,_}|_] -> [{}]; _ -> V end end}]),
             [
                 start_object,
                 end_object,
@@ -833,7 +833,7 @@ pre_encoders_test_() ->
             ]
         )},
         {"replace all non-list values with false", ?_assertEqual(
-            encode(Term, [{pre_encoders, [fun(V) when is_list(V) -> V; (_) -> false end]}]),
+            encode(Term, [{pre_encoder, fun(V) when is_list(V) -> V; (_) -> false end}]),
             [
                 start_object,
                     {key, <<"object">>}, start_object,
@@ -852,7 +852,7 @@ pre_encoders_test_() ->
             ]
         )},
         {"replace all atoms with atom_to_list", ?_assertEqual(
-            encode(Term, [{pre_encoders, [fun(V) when is_atom(V) -> unicode:characters_to_binary(atom_to_list(V)); (V) -> V end]}]),
+            encode(Term, [{pre_encoder, fun(V) when is_atom(V) -> unicode:characters_to_binary(atom_to_list(V)); (V) -> V end}]),
             [
                 start_object,
                     {key, <<"object">>}, start_object,
diff --git a/src/jsx_utils.erl b/src/jsx_utils.erl
index 2afd8db..a889cb5 100644
--- a/src/jsx_utils.erl
+++ b/src/jsx_utils.erl
@@ -61,6 +61,9 @@ parse_opts([relax|Rest], Opts) ->
         comments = true,
         ignored_bad_escapes = true
     });
+parse_opts([{pre_encoder, Encoder}|Rest], Opts) when is_function(Encoder, 1) ->
+    AllEncoders = Opts#opts.pre_encoders ++ [Encoder],
+    parse_opts(Rest, Opts#opts{pre_encoders=AllEncoders});
 parse_opts([{pre_encoders, Encoders}|Rest], Opts) when is_list(Encoders) ->
     lists:foreach(fun(F) when is_function(F, 1) -> ok end, Encoders),
     AllEncoders = Opts#opts.pre_encoders ++ Encoders,
@@ -94,6 +97,7 @@ valid_flags() ->
         ignored_bad_escapes,
         explicit_end,
         relax,
+        pre_encoder,
         pre_encoders,
         %% deprecated flags
         loose_unicode,          %% replaced_bad_utf8