add JSX_FORCE_MAPS flag for forcing decoding to maps

CHANGES.md

@@ -1,3 +1,8 @@
+v2.8.0
+
+* add `JSX_FORCE_MAPS` env var for forcing decoding to maps rather than
+  attempting to autodetect
+
 v2.7.2
 
 * fix an issue where tuples were assumed to be jsx ast and not checked

README.md

@@ -4,7 +4,7 @@
 an erlang application for consuming, producing and manipulating [json][json]. 
 inspired by [yajl][yajl]
 
-**jsx** is built via [rebar][rebar] and continuous integration testing provided courtesy [travis-ci][travis]
+**jsx** is built via [rebar3][rebar3], [rebar][rebar] or [mix][mix] and continuous integration testing provided courtesy [travis-ci][travis]
 
 current status: [![Build Status](https://secure.travis-ci.org/talentdeficit/jsx.png?branch=develop)](http://travis-ci.org/talentdeficit/jsx)
 
@@ -51,8 +51,12 @@ for the overview or [migrating from 1.x](#migrating) for the details
 #### to build the library and run tests ####
 
 ```bash
+$ rebar3 compile
+$ rebar3 eunit
 $ rebar compile
 $ rebar eunit
+$ mix compile
+$ mix eunit
 ```
 
 #### to convert a utf8 binary containing a json string into an erlang term ####
@@ -116,6 +120,12 @@ false
 }">>
 ```
 
+#### to compile **jsx** so that it always decodes json objects to maps #### 
+
+```bash
+$ JSX_FORCE_MAPS rebar3 compile
+$ JSX_FORCE_MAPS mix compile
+```
 
 ## description ##
 
@@ -720,7 +730,9 @@ jsx wouldn't be what it is without the contributions of [Paul J. Davis](https://
 [json]: http://json.org
 [yajl]: http://lloyd.github.com/yajl
 [MIT]: http://www.opensource.org/licenses/mit-license.html
+[rebar3]: https://rebar3.org
 [rebar]: https://github.com/rebar/rebar
+[mix]: http://elixir-lang.org/getting-started/mix-otp/introduction-to-mix.html
 [meck]: https://github.com/eproxus/meck
 [rfc4627]: http://tools.ietf.org/html/rfc4627
 [travis]: https://travis-ci.org/

mix.exs

@@ -14,7 +14,13 @@ use Mix.Project
   end
 
   defp opts(:dev), do: [d: :TEST] ++ opts(:prod)
-  defp opts(_), do: [d: :maps_support, d: :maps_always]
+  defp opts(_) do
+    force_maps = case System.get_env("JSX_FORCE_MAPS") do
+      nil -> []
+      _   -> [d: :maps_always]
+    end
+    [d: :maps_support] ++ force_maps
+  end 
 
   defp deps(_), do: [{:mixunit, "~> 0.9.2", only: :dev}]
 

rebar.config

@@ -1,6 +1 @@
-{erl_opts, [
-  % uncomment to always decode to maps
-  % {d, maps_always},
-]}.
-
 {edoc_opts, [{preprocess, true}]}.

rebar.config.script

@@ -3,9 +3,13 @@ Def0 = case erlang:is_builtin(erlang, binary_to_integer, 1) andalso
            true -> [];
            false -> [{d, no_binary_to_whatever}]
        end,
-Defs = case erlang:is_builtin(erlang, is_map, 1) of
+Def1 = case erlang:is_builtin(erlang, is_map, 1) of
            true -> [{d, maps_support}|Def0];
            false -> Def0
        end,
+Defs = case os:getenv("JSX_FORCE_MAPS") of
+           false -> Def1;
+           _ -> [{d, maps_always}|Def1]
+       end,
 lists:keystore(erl_opts, 1, CONFIG,
                {erl_opts, proplists:get_value(erl_opts, CONFIG, []) ++ Defs}).