From 75bca45b9053255b4c4342c902582f1a150ec9d2 Mon Sep 17 00:00:00 2001
From: fishtreesugar <fishtreesugar@gmail.com>
Date: Mon, 4 Mar 2024 16:00:01 -0600
Subject: [PATCH] fix: return error when embeds_many field input with wrong
 type

fixes https://github.com/bitwalker/strukt/issues/18
---
 lib/params.ex        |  7 +++++--
 lib/strukt.ex        |  2 +-
 test/strukt_test.exs | 13 +++++++++++++
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/lib/params.ex b/lib/params.ex
index 3012c7a..e1bfbb5 100644
--- a/lib/params.ex
+++ b/lib/params.ex
@@ -30,13 +30,13 @@ defmodule Strukt.Params do
     transform(module, params, struct)
   end
 
-  defp transform(module, params, nil = struct, cardinality: :many) do
+  defp transform(module, params, nil = struct, cardinality: :many) when is_list(params) do
     Enum.map(params, fn param ->
       transform(module, param, struct)
     end)
   end
 
-  defp transform(module, params, struct, cardinality: :many) do
+  defp transform(module, params, struct, cardinality: :many) when is_list(params) do
     params
     |> Enum.with_index()
     |> Enum.map(fn {param, index} ->
@@ -44,6 +44,9 @@ defmodule Strukt.Params do
     end)
   end
 
+  # for delay the type error to casting
+  defp transform(_module, params, _struct, cardinality: :many), do: params
+
   defp transform_from_struct(module, params, struct) do
     struct
     |> Map.from_struct()
diff --git a/lib/strukt.ex b/lib/strukt.ex
index 5d92d04..7538e19 100644
--- a/lib/strukt.ex
+++ b/lib/strukt.ex
@@ -565,7 +565,7 @@ defmodule Strukt do
                 # When we have a list of entities, we are overwriting the embeds with a new set
                 Ecto.Changeset.put_embed(changeset, field, Enum.map(entities, &Map.from_struct/1))
 
-              other when is_map(other) or is_list(other) ->
+              other ->
                 # For all other parameters, we need to cast. Depending on how the embedded entity is configured, this may raise an error
                 cast_embed(changeset, field)
             end
diff --git a/test/strukt_test.exs b/test/strukt_test.exs
index a624f94..02c66a6 100644
--- a/test/strukt_test.exs
+++ b/test/strukt_test.exs
@@ -295,6 +295,19 @@ defmodule Strukt.Test do
     refute is_nil(uuid)
   end
 
+  test "return error when passing wrong typed value to embeds_many field" do
+    {:error,
+     %Ecto.Changeset{
+       action: :insert,
+       changes: %{},
+       errors: [items: {"is invalid", [validation: :embed, type: {:array, :map}]}],
+       valid?: false
+     }} =
+      Fixtures.CustomFieldsWithEmbeddedSchema.new(%{
+        items: "iterms"
+      })
+  end
+
   test "parse custom fields with boolean value" do
     assert {:ok, %Strukt.Test.Fixtures.CustomFieldsWithBoolean{enabled: false, uuid: uuid}} =
              Fixtures.CustomFieldsWithBoolean.new(%{Enabled: false})