Preload only collection associations to avoid "to_a is obsolete" warnings

lib/simple_form.rb

@@ -91,13 +91,14 @@ module SimpleForm
   mattr_accessor :required_by_default
   @@required_by_default = true
 
-  # Tell browsers whether to use default HTML5 validations.
+  # Tell browsers whether to use default HTML5 validations (novalidate option).
   mattr_accessor :browser_validations
   @@browser_validations = true
 
-  # Determines whether HTML5 types (:email, :url, :search, :tel) and attributes (e.g. required) are used
-  # or not. True by default.
-  # Having this on in non-HTML5 compliant sites can cause odd behavior in HTML5-aware browsers such as Chrome.
+  # Determines whether HTML5 types (:email, :url, :search, :tel) and attributes
+  # (e.g. required) are used or not. True by default.
+  # Having this on in non-HTML5 compliant sites can cause odd behavior in
+  # HTML5-aware browsers such as Chrome.
   mattr_accessor :html5
   @@html5 = true
 

lib/simple_form/form_builder.rb

@@ -164,13 +164,13 @@ module SimpleForm
             html_options[:multiple] = true unless html_options.key?(:multiple)
           end
 
-          :"#{reflection.name.to_s.singularize}_ids"
-      end
+          # Force the association to be preloaded for performance.
+          if options[:preload] != false && object.respond_to?(association)
+            target = object.send(association)
+            target.to_a if target.respond_to?(:to_a)
+          end
 
-      # Force the association to be preloaded for performance.
-      if options[:preload] != false && object.respond_to?(association)
-        target = object.send(association)
-        target.to_a if target.respond_to?(:to_a)
+          :"#{reflection.name.to_s.singularize}_ids"
       end
 
       input(attribute, options.merge(:reflection => reflection))

test/form_builder_test.rb

@@ -585,17 +585,27 @@ class FormBuilderTest < ActionView::TestCase
     end
   end
 
-  test 'builder caches given association' do
-    value = @user.company
+  test 'builder preloads collection association' do
+    value = @user.tags
     value.expects(:to_a).returns(value)
-    with_association_for @user, :company
+    with_association_for @user, :tags
+    assert_select 'form select.select#user_tag_ids'
+    assert_select 'form select option[value=1]', 'Tag 1'
+    assert_select 'form select option[value=2]', 'Tag 2'
+    assert_select 'form select option[value=3]', 'Tag 3'
+  end
+
+  test 'builder does not preload collection association if preload false' do
+    value = @user.company
+    value.expects(:to_a).never
+    with_association_for @user, :company, :preload => false
     assert_select 'form select.select#user_company_id'
     assert_select 'form select option[value=1]', 'Company 1'
     assert_select 'form select option[value=2]', 'Company 2'
     assert_select 'form select option[value=3]', 'Company 3'
   end
 
-  test 'builder does not cache given association if preload false' do
+  test 'builder does not preload non collection association' do
     value = @user.company
     value.expects(:to_a).never
     with_association_for @user, :company, :preload => false

test/support/models.rb

@@ -38,10 +38,11 @@ class User
   extend ActiveModel::Naming
   include ActiveModel::Conversion
 
-  attr_accessor :id, :name, :company, :company_id, :time_zone, :active, :description, :created_at, :updated_at,
-    :credit_limit, :age, :password, :delivery_time, :born_at, :special_company_id, :country, :url, :tag_ids,
-    :avatar, :home_picture, :email, :status, :residence_country, :phone_number, :post_count, :lock_version,
-    :amount, :attempts
+  attr_accessor :id, :name, :company, :company_id, :time_zone, :active, :age,
+    :description, :created_at, :updated_at, :credit_limit, :password, :url,
+    :delivery_time, :born_at, :special_company_id, :country, :tags, :tag_ids,
+    :avatar, :home_picture, :email, :status, :residence_country, :phone_number,
+    :post_count, :lock_version, :amount, :attempts
 
   def initialize(options={})
     options.each do |key, value|