Fixed Calling << to an ActiveModel::Errors deprecation warning

lib/bootstrap_form/components/validation.rb

@@ -65,16 +65,20 @@ def generate_error(name)
         content_tag(help_tag, help_text, class: help_klass)
       end
 
+      # rubocop:disable Metrics/AbcSize
       def get_error_messages(name)
-        messages = object.errors[name]
         object.class.try(:reflections)&.each do |association_name, a|
           next unless a.is_a?(ActiveRecord::Reflection::BelongsToReflection)
           next unless a.foreign_key == name.to_s
 
-          messages << object.errors[association_name]
+          object.errors[association_name].each do |error|
+            object.errors.add(name, error)
+          end
         end
-        messages.join(", ")
+
+        object.errors[name].join(", ")
       end
+      # rubocop:enable Metrics/AbcSize
     end
   end
 end

test/bootstrap_checkbox_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapCheckboxTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper

test/bootstrap_configuration_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapConfigurationTest < ActionView::TestCase
   test "has default form attributes" do

test/bootstrap_fields_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapFieldsTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper
@@ -100,6 +100,22 @@ class BootstrapFieldsTest < ActionView::TestCase
     assert_equivalent_html expected, bootstrap_form_for(@user) { |f| f.file_field(:misc) }
   end
 
+  test "errors are correctly displayed for belongs_to assoication fields" do
+    @address.valid?
+
+    expected = <<~HTML
+      <form accept-charset="UTF-8" action="/users" class="new_address"  id="new_address" method="post">
+        #{'<input name="utf8" type="hidden" value="&#x2713;"/>' unless ::Rails::VERSION::STRING >= '6'}
+        <div class="mb-3">
+          <label class="form-label required" for="address_user_id">User</label>
+          <input aria-required="true" class="form-control is-invalid" id="address_user_id" name="address[user_id]" required="required" type="text"/>
+          <div class="invalid-feedback">must exist</div>
+        </div>
+      </form>
+    HTML
+    assert_equivalent_html expected, bootstrap_form_for(@address, url: users_path) { |f| f.text_field(:user_id) }
+  end
+
   test "hidden fields are supported" do
     expected = <<~HTML
       <input #{autocomplete_attr} id="user_misc" name="user[misc]" type="hidden" />

test/bootstrap_form_group_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapFormGroupTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper

test/bootstrap_form_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapFormTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper

test/bootstrap_other_components_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapOtherComponentsTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper

test/bootstrap_radio_button_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapRadioButtonTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper

test/bootstrap_rich_text_area_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 require "minitest/mock"
 
 if Rails::VERSION::STRING > "6"

test/bootstrap_selects_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapSelectsTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper

test/bootstrap_without_fields_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class BootstrapWithoutFieldsTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper

test/special_form_class_models_test.rb

@@ -1,4 +1,4 @@
-require_relative "./test_helper"
+require_relative "test_helper"
 
 class SpecialFormClassModelsTest < ActionView::TestCase
   include BootstrapForm::ActionViewExtensions::FormHelper

test/test_helper.rb

@@ -12,6 +12,7 @@
 
 class ActionView::TestCase
   def setup_test_fixture
+    @address = Address.new(street: "Foo")
     @user = User.new(email: "steve@example.com", password: "secret", comments: "my comment")
     @builder = BootstrapForm::FormBuilder.new(:user, @user, self, {})
     @horizontal_builder = BootstrapForm::FormBuilder.new(:user, @user, self,