Support custom newline symbol(s) for format option

.gitignore

@@ -8,3 +8,7 @@ erl_crash.dump
 .DS_Store
 doc
 .rebar
+*.sublime-*
+rebar3
+_build/
+

README.md

@@ -572,8 +572,9 @@ format(JSON) -> JSON
 format(JSON, Opts) -> JSON
 
   JSON = json_text()
-  Opts = [option() | space | {space, N} | indent | {indent, N}]
-    N = pos_integer()
+  Opts = [option() | space | {space, N} | indent | {indent, N} | {newline, LF}]
+     N = pos_integer()
+    LF = binary()
 ```
 
 `format` parses a json text (a `utf8` encoded binary) and produces a new json 
@@ -586,6 +587,9 @@ the option `{indent, N}` inserts a newline and `N` spaces for each level of
 indentation in your json output. note that this overrides spaces inserted after 
 a comma. `indent` is an alias for `{indent, 1}`. the default is `{indent, 0}`
 
+the option `{newline, LF}` defines a custom newline symbol(s). 
+the default is `{newline, <<$\n>>}`
+
 raises a `badarg` error exception if input is not valid json
 
 

src/jsx_to_json.erl

@@ -32,7 +32,8 @@
 -record(config, {
     space = 0,
     indent = 0,
-    depth = 0
+    depth = 0,
+    newline = <<$\n>>
 }).
 
 -type config() :: list().
@@ -62,6 +63,8 @@ parse_config([{indent, Val}|Rest], Config) when is_integer(Val), Val > 0 ->
     parse_config(Rest, Config#config{indent = Val});
 parse_config([indent|Rest], Config) ->
     parse_config(Rest, Config#config{indent = 1});
+parse_config([{newline, Val}|Rest], Config) when is_binary(Val) ->
+    parse_config(Rest, Config#config{newline = Val});
 parse_config([{K, _}|Rest] = Options, Config) ->
     case lists:member(K, jsx_config:valid_flags()) of
         true -> parse_config(Rest, Config)
@@ -128,7 +131,7 @@ space(Config) ->
 indent(Config) ->
     case Config#config.indent of
         0 -> <<>>
-        ; X when X > 0 -> <<?newline/binary, (binary:copy(?space, X * Config#config.depth))/binary>>
+        ; X when X > 0 -> <<(Config#config.newline)/binary, (binary:copy(?space, X * Config#config.depth))/binary>>
     end.
 
 
@@ -383,6 +386,13 @@ format_test_() ->
     [{Title, ?_assertEqual(Min, jsx:minify(Pretty))} || {Title, Min, Pretty} <- Cases] ++
         [{Title, ?_assertEqual(Pretty, jsx:prettify(Min))} || {Title, Min, Pretty} <- Cases].
 
+custom_newline_test_() ->
+    [
+        {"single key object", ?_assert(
+            jsx:format(<<"{\"k\":\"v\"}">>, [space, {indent, 2}, {newline, <<$\r>>}]) 
+                =:= <<"{\r  \"k\": \"v\"\r}">>)
+        }
+    ].
 
 handle_event_test_() ->
     Data = jsx:test_cases() ++ jsx:special_test_cases(),