test: add unit tests for Role validations

Add tests for permission_set_name validation, system role
deletion protection, and name uniqueness constraints.

test/mv/authorization/role_test.exs

@@ -0,0 +1,93 @@
+defmodule Mv.Authorization.RoleTest do
+  @moduledoc """
+  Unit tests for Role resource validations and constraints.
+  """
+  use Mv.DataCase, async: true
+
+  alias Mv.Authorization
+
+  describe "permission_set_name validation" do
+    test "accepts valid permission set names" do
+      attrs = %{
+        name: "Test Role",
+        permission_set_name: "own_data"
+      }
+
+      assert {:ok, role} = Authorization.create_role(attrs)
+      assert role.permission_set_name == "own_data"
+    end
+
+    test "rejects invalid permission set names" do
+      attrs = %{
+        name: "Test Role",
+        permission_set_name: "invalid_set"
+      }
+
+      assert {:error, %Ash.Error.Invalid{errors: errors}} = Authorization.create_role(attrs)
+      assert error_message(errors, :permission_set_name) =~ "must be one of"
+    end
+
+    test "accepts all four valid permission sets" do
+      valid_sets = ["own_data", "read_only", "normal_user", "admin"]
+
+      for permission_set <- valid_sets do
+        attrs = %{
+          name: "Role #{permission_set}",
+          permission_set_name: permission_set
+        }
+
+        assert {:ok, _role} = Authorization.create_role(attrs)
+      end
+    end
+  end
+
+  describe "system role deletion protection" do
+    test "prevents deletion of system roles" do
+      {:ok, system_role} =
+        Authorization.create_role(%{
+          name: "System Role",
+          permission_set_name: "own_data",
+          is_system_role: true
+        })
+
+      assert {:error, %Ash.Error.Invalid{errors: errors}} =
+               Authorization.destroy_role(system_role)
+
+      message = error_message(errors, nil)
+      assert message =~ "Cannot delete system role"
+    end
+
+    test "allows deletion of non-system roles" do
+      {:ok, regular_role} =
+        Authorization.create_role(%{
+          name: "Regular Role",
+          permission_set_name: "read_only",
+          is_system_role: false
+        })
+
+      assert :ok = Authorization.destroy_role(regular_role)
+    end
+  end
+
+  describe "name uniqueness" do
+    test "enforces unique role names" do
+      attrs = %{
+        name: "Unique Role",
+        permission_set_name: "own_data"
+      }
+
+      assert {:ok, _} = Authorization.create_role(attrs)
+
+      assert {:error, %Ash.Error.Invalid{errors: errors}} = Authorization.create_role(attrs)
+      assert error_message(errors, :name) =~ "has already been taken"
+    end
+  end
+
+  # Helper function for error evaluation
+  defp error_message(errors, field) do
+    errors
+    |> Enum.filter(fn err -> Map.get(err, :field) == field end)
+    |> Enum.map(&Map.get(&1, :message, ""))
+    |> List.first() || ""
+  end
+end