Fix typespec

Source needs to be defined as a binary.

src/hz.erl

@@ -788,9 +788,9 @@ contract_code(ID) ->
          Result :: {ok,      Source}
                  | {project, Bundle}
                  | {error,   Reason},
-         Source :: string(),
+         Source :: binary(),
          Bundle :: [{FilePath :: string(), Contents :: binary()}],
-         Reason   :: chain_error() | string().
+         Reason :: chain_error() | string().
 %% @doc
 %% Retrieve the code of a contract as represented on chain.
 
@@ -801,23 +801,21 @@ contract_source(ID) ->
         Error                       -> Error
     end.
 
-extract(<<"ba_", _/binary>> = Blobby) ->
+extract(Blobby) ->
     case gmser_api_encoder:safe_decode(bytearray, Blobby) of
-        {ok, TarBaby} -> extract2(TarBaby);
-        {error, invalid_encoding} -> {ok, unicode:characters_to_list(Blobby)}
-    end;
-extract(Blobby) when is_binary(Blobby) ->
-    {ok, unicode:characters_to_list(Blobby)}.
+        {ok, TarBaby}             -> extract2(TarBaby);
+        {error, invalid_encoding} -> {ok, Blobby}
+    end.
 
 extract2(TarBaby) ->
     case erl_tar:extract({binary, TarBaby}, [memory, compressed]) of
         {ok, [{_File, Source}]} ->
-            {ok, unicode:characters_to_list(Source)};
+            {ok, Source};
         {ok, Bundle} ->
             {project, Bundle};
         Error ->
             io:format("Dis chit happen: ~tp~n", [Error]),
-            {ok, unicode:characters_to_list(TarBaby)}
+            {ok, TarBaby}
     end.