fix: don't double wrap casted struct instances in {:ok, {:ok, ...}}

fix: support mixed key types in input maps for structs

lib/ash/type/struct.ex

@@ -273,17 +273,16 @@ defmodule Ash.Type.Struct do
               if Enum.all?(keys, &is_atom/1) do
                 {:ok, struct(struct, value)}
               else
-                {:ok,
-                 Map.delete(struct.__struct__, :__struct__)
-                 |> Enum.reduce({:ok, struct(struct)}, fn {key, _value}, {:ok, acc} ->
-                   case Map.fetch(value, to_string(key)) do
-                     {:ok, val} ->
-                       {:ok, Map.put(acc, key, val)}
-
-                     :error ->
-                       {:ok, acc}
-                   end
-                 end)}
+                Map.delete(struct.__struct__(), :__struct__)
+                |> Enum.reduce({:ok, struct(struct)}, fn {key, _value}, {:ok, acc} ->
+                  with :error <- Map.fetch(value, key),
+                       :error <- Map.fetch(value, to_string(key)) do
+                    {:ok, acc}
+                  else
+                    {:ok, val} ->
+                      {:ok, Map.put(acc, key, val)}
+                  end
+                end)
               end
             end
         end

test/type/struct_test.exs

@@ -7,6 +7,15 @@ defmodule Type.StructTest do
     defstruct [:foo, :bar]
   end
 
+  defmodule Embedded do
+    use Ash.Resource, data_layer: :embedded
+
+    attributes do
+      attribute :name, :string, allow_nil?: false
+      attribute :title, :string, allow_nil?: false
+    end
+  end
+
   defmodule Post do
     @moduledoc false
     use Ash.Resource, domain: Domain, data_layer: Ash.DataLayer.Ets
@@ -42,6 +51,13 @@ defmodule Type.StructTest do
     end
   end
 
+  test "an embedded resource can be used" do
+    assert {:ok, %Embedded{name: "fred", title: "title"}} =
+             Ash.Type.apply_constraints(Ash.Type.Struct, %{"name" => "fred", :title => "title"},
+               instance_of: Embedded
+             )
+  end
+
   test "it handles valid maps" do
     changeset =
       Post