Allow non-sequential arguments (#29)

* Allow non-sequential argument numbers

* Demonstrate bug with non-sequential args

lib/riffed/client.ex

@@ -66,7 +66,7 @@ defmodule Riffed.Client do
 
     reply_meta = Riffed.Enumeration.get_overridden_type(function_name, :return_type, overrides, reply_meta)
 
-    arg_list = build_arg_list(length(param_meta))
+    arg_list = build_arg_list(param_meta)
     {:{}, _, list_args} = build_handler_tuple_args(param_meta)
     casts = build_casts(function_name, struct_module, param_meta, overrides, :to_erlang)
 

lib/riffed/macro_helpers.ex

@@ -1,18 +1,12 @@
 defmodule Riffed.MacroHelpers do
   @moduledoc false
-  def build_arg_list(size) when is_integer(size) do
-    case size do
-      0 -> []
-      size ->
-          Enum.map(1..size, fn(param_idx) ->
-                     :"arg_#{param_idx}"
-                     |> Macro.var(nil)
-                   end)
-    end
+  def build_arg_list(param_meta) do
+    param_meta
+    |> Enum.map(&build_arg(&1))
   end
 
   def build_handler_tuple_args(param_meta) do
-    args =  param_meta |> length |> build_arg_list
+    args =  build_arg_list(param_meta)
     {:{}, [], args}
   end
 
@@ -21,6 +15,10 @@ defmodule Riffed.MacroHelpers do
     |> Enum.map(&build_arg_cast(function_name, struct_module, &1, overrides, cast_function))
   end
 
+  defp build_arg({index, _type}=arg) do
+    Macro.var(:"arg_#{abs(index)}", nil)
+  end
+
   defp build_arg_cast(function_name, struct_module, param_meta, overrides, cast_function) do
     {index, param_type} = param_meta
     param_name = :"arg_#{abs(index)}"

lib/riffed/server.ex

@@ -101,10 +101,10 @@ defmodule Riffed.Server do
     end
   end
 
-  defp build_delegate_call(delegate_fn) do
+  defp build_delegate_call(delegate_fn, params_meta) do
     delegate_info = :erlang.fun_info(delegate_fn)
 
-    arg_list = build_arg_list(delegate_info[:arity])
+    arg_list = build_arg_list(params_meta)
 
     {{:., [], [{:__aliases__, [alias: false],
                 [delegate_info[:module]]}, delegate_info[:name]]}, [], arg_list}
@@ -116,7 +116,7 @@ defmodule Riffed.Server do
     params_meta = function_meta[:params]
     reply_meta = function_meta[:reply] |> Riffed.Struct.to_riffed_type_spec
     tuple_args = build_handler_tuple_args(params_meta)
-    delegate_call = build_delegate_call(delegate_fn)
+    delegate_call = build_delegate_call(delegate_fn, params_meta)
     casts = build_casts(thrift_fn_name, struct_module, params_meta, fn_overrides, :to_elixir)
     overridden_type = Riffed.Enumeration.get_overridden_type(thrift_fn_name, :return_type, fn_overrides, reply_meta)
 

thrift/server.thrift

@@ -40,7 +40,7 @@ struct UserBoardResponse {
 
 service Server {
   ConfigResponse config(1: ConfigRequest request, 2: i32 timestamp);
-  ActivityState setUserState(1: User user, 2: ActivityState status);
+  ActivityState setUserState(10: User user, 20: ActivityState status);
   map<string, i32> dictFun(1: map<string, i32> dict);
   map<string, User> dictUserFun(1: map<string, User> dict);
   set<string> setFun(1: set<string> mySet);