Support non-AR form objects (#151)

app/presenters/hotwire_combobox/component.rb

@@ -248,7 +248,7 @@ def associated_object
     end
 
     def association_exists?
-      form_object&.class&.reflect_on_association(association_name).present?
+      association_name && form_object&.respond_to?(association_name)
     end
 
     def form_object
@@ -300,7 +300,7 @@ def hidden_field_data
     def hidden_field_value
       return value if value
 
-      if form_object&.defined_enums&.try :[], name
+      if form_object&.try(:defined_enums)&.try(:[], name)
         form_object.public_send "#{name}_before_type_cast"
       else
         form_object&.try(name).then do |value|

test/dummy/app/controllers/comboboxes_controller.rb

@@ -98,6 +98,10 @@ def morph
     @user = User.where.not(home_state: nil).first || raise("No user found with home state, load fixtures first.")
   end
 
+  def form_object
+    @object = Form.new
+  end
+
   private
     delegate :combobox_options, :html_combobox_options, to: "ApplicationController.helpers", private: true
 

test/dummy/app/models/form.rb

@@ -0,0 +1,14 @@
+class Form
+  include ActiveModel::Model
+  include ActiveModel::Attributes
+
+  attr_accessor :state_id
+
+  def state
+    State.find state_id
+  end
+
+  def state_id
+    @state_id || State.first.id
+  end
+end

test/dummy/app/views/comboboxes/form_object.html.erb

@@ -0,0 +1,4 @@
+<%= form_with model: @object, url: "#" do |form| %>
+  <%= form.combobox :state_id, states_path %>
+  <%= form.submit %>
+<% end %>

test/dummy/config/routes.rb

@@ -29,6 +29,7 @@
   get "multiselect_new_values", to: "comboboxes#multiselect_new_values"
   get "grouped_options", to: "comboboxes#grouped_options"
   get "morph", to: "comboboxes#morph"
+  get "form_object", to: "comboboxes#form_object"
 
   resources :movies, only: %i[ index update ]
   get "movies_html", to: "movies#index_html"

test/system/hotwire_combobox_test.rb

@@ -1162,6 +1162,12 @@ class HotwireComboboxTest < ApplicationSystemTestCase
       user.visited_states.map(&:id)
   end
 
+  test "POROs as form objects" do
+    visit form_object_path
+
+    assert_combobox_display_and_value "#form_state_id", "Alabama", states(:alabama).id
+  end
+
   private
     def open_combobox(selector)
       find(selector).click