Fix the nested versioned fields bug

config/config.exs

@@ -1,6 +1,6 @@
 # This file is responsible for configuring your application
 # and its dependencies with the aid of the Mix.Config module.
-use Mix.Config
+import Config
 
 # This configuration is loaded before any dependency and is restricted
 # to this project. If another project depends on this project, this

lib/exgencode.ex

@@ -416,7 +416,8 @@ defmodule Exgencode do
                 field_name,
                 props
               ),
-              props[:version]
+              props[:version],
+              props[:type]
             )
 
           decode_fun =
@@ -426,7 +427,8 @@ defmodule Exgencode do
                 field_name,
                 props
               ),
-              props[:version]
+              props[:version],
+              props[:type]
             )
 
           {field_name, [{:encode, encode_fun}, {:decode, decode_fun} | props]}
@@ -435,11 +437,16 @@ defmodule Exgencode do
           encode_fun =
             Exgencode.EncodeDecode.create_versioned_encode(
               Exgencode.EncodeDecode.wrap_custom_encode(field_name, props[:encode]),
-              props[:version]
+              props[:version],
+              props[:type]
             )
 
           decode_fun =
-            Exgencode.EncodeDecode.create_versioned_decode(props[:decode], props[:version])
+            Exgencode.EncodeDecode.create_versioned_decode(
+              props[:decode],
+              props[:version],
+              props[:type]
+            )
 
           {field_name,
            props

lib/exgencode/encode_decode.ex

@@ -3,11 +3,15 @@ defmodule Exgencode.EncodeDecode do
   Helper functions for generating encoding and decoding functions.
   """
 
-  def create_versioned_encode(function, nil) do
+  def create_versioned_encode(function, nil, :subrecord) do
+    quote do: fn version -> unquote(function) end
+  end
+
+  def create_versioned_encode(function, nil, _) do
     quote do: fn _ -> unquote(function) end
   end
 
-  def create_versioned_encode(function, version) do
+  def create_versioned_encode(function, version, _) do
     quote do
       fn
         nil ->
@@ -23,11 +27,15 @@ defmodule Exgencode.EncodeDecode do
     end
   end
 
-  def create_versioned_decode(function, nil) do
+  def create_versioned_decode(function, nil, :subrecord) do
+    quote do: fn version -> unquote(function) end
+  end
+
+  def create_versioned_decode(function, nil, _) do
     quote do: fn _ -> unquote(function) end
   end
 
-  def create_versioned_decode(function, version) do
+  def create_versioned_decode(function, version, _) do
     quote do
       fn
         nil ->
@@ -46,7 +54,7 @@ defmodule Exgencode.EncodeDecode do
   def create_encode_fun(:subrecord, field_name, props) do
     basic_fun =
       quote do: fn %{unquote(field_name) => field_val} ->
-              <<Exgencode.Pdu.encode(field_val)::bitstring>>
+              <<Exgencode.Pdu.encode(field_val, version)::bitstring>>
             end
 
     wrap_conditional_encode(props, basic_fun)
@@ -185,7 +193,7 @@ defmodule Exgencode.EncodeDecode do
     basic_fun =
       quote do
         fn pdu, binary ->
-          {field_value, rest_binary} = Exgencode.Pdu.decode(unquote(default), binary)
+          {field_value, rest_binary} = Exgencode.Pdu.decode(unquote(default), binary, version)
           {struct!(pdu, %{unquote(field_name) => field_value}), rest_binary}
         end
       end

mix.exs

@@ -4,7 +4,7 @@ defmodule Exgencode.Mixfile do
   def project do
     [
       app: :exgencode,
-      version: "2.5.1",
+      version: "2.5.2",
       elixir: "~> 1.7",
       start_permanent: Mix.env() == :prod,
       deps: deps(),

test/exgencode_test.exs

@@ -58,6 +58,14 @@ defmodule ExgencodeTest do
     assert <<10::size(16)>> == Exgencode.Pdu.encode(pdu, "1.0.0")
     assert <<10::size(16), 111::size(8)>> == Exgencode.Pdu.encode(pdu, "2.0.0")
     assert <<10::size(16), 111::size(8), 14::size(8)>> == Exgencode.Pdu.encode(pdu, "2.1.0")
+
+    nested_pdu = %TestPdu.NestedVersionedMsg{nested: pdu}
+
+    assert <<2::size(16), 10::size(16), 111::size(8), 14::size(8)>> ==
+             Exgencode.Pdu.encode(nested_pdu)
+
+    assert <<2::size(16), 10::size(16), 111::size(8)>> ==
+             Exgencode.Pdu.encode(nested_pdu, "2.0.0")
   end
 
   test "versioning decode" do
@@ -76,6 +84,14 @@ defmodule ExgencodeTest do
 
     assert {%TestPdu.VersionedMsg{}, <<111::size(8), 14::size(8)>>} =
              Exgencode.Pdu.decode(%TestPdu.VersionedMsg{}, binary, "1.0.0")
+
+    nested_pdu = %TestPdu.NestedVersionedMsg{nested: %TestPdu.VersionedMsg{}}
+    binary = <<2::size(16), 10::size(16)>>
+    assert {^nested_pdu, <<>>} = Exgencode.Pdu.decode(%TestPdu.NestedVersionedMsg{}, binary, "1.0.0")
+
+    nested_pdu = %TestPdu.NestedVersionedMsg{nested: %TestPdu.VersionedMsg{newerField: 111}}
+    binary = <<2::size(16), 10::size(16), 111::size(8)>>
+    assert {^nested_pdu, <<>>} = Exgencode.Pdu.decode(%TestPdu.NestedVersionedMsg{}, binary, "2.0.0")
   end
 
   test "versioned encode/decode symmetry" do

test/helpers/test_pdu.ex

@@ -34,6 +34,10 @@ defmodule Exgencode.TestPdu do
       end
     ]
 
+  defpdu NestedVersionedMsg,
+    someField: [size: 16, default: 2],
+    nested: [type: :subrecord, default: %VersionedMsg{}]
+
   defpdu EndianMsg,
     bigField: [default: 15, size: 32, endianness: :big],
     smallField: [default: 15, size: 32, endianness: :little]