Adding :include and :joins options to association finds.

README.rdoc

@@ -161,19 +161,15 @@ Simple enough right? This is going to render a :select input for choosing the :c
     f.association :company, :as => :radio
     f.association :roles, :as => :check_boxes
 
-And you will get a set of radios to select the company and another set of check boxes for the roles. Some options are available for refining the collection for associations:
+And you will get a set of radios to select the company and another set of check boxes for the roles. Some options are available for refining the collection for associations: :conditions, :include, :joins, :order. These options are given straight to the find method. Here is an example of how to use these options:
 
-* conditions => given as conditions for retrieving the collection
-
-* order => given as order for retrieving the collection
-
-* scopes => named scopes to be called for retrieving the collection
-
-Here is an example of how to use this options:
-
-  f.association :company, :order => 'name', :scopes => :active
+  f.association :company, :order => 'name'
   f.association :roles, :conditions => { :active => true }
 
+You also have the ability to call named scopes using the association:
+
+  f.association :company, :scope => [:active, :available]
+
 The association helper just invokes input under the hood, so all options available to :select, :radio and :check_boxes are also available to association. For example, you can specify the collection by hand, all together with the prompt:
 
   f.association :company, :collection => Company.active.all(:order => 'name'), :prompt => "Choose a Company"

lib/simple_form/form_builder.rb

@@ -91,6 +91,10 @@ module SimpleForm
     #
     # * :conditions - Given as conditions when retrieving the collection
     #
+    # * :include - Given as include when retrieving the collection
+    #
+    # * :joins - Given as joins when retrieving the collection
+    #
     # * :order - Given as order when retrieving the collection
     #
     # * :scope - Given as scopes when retrieving the collection
@@ -136,7 +140,7 @@ module SimpleForm
       end
 
       options[:collection] ||= begin
-        find_options = options.slice(:conditions, :order)
+        find_options = options.slice(:conditions, :order, :include, :joins)
         klass = Array(options[:scope]).inject(@reflection.klass) do |klass, scope|
           klass.send(scope)
         end

test/form_builder_test.rb

@@ -410,6 +410,22 @@ class FormBuilderTest < ActionView::TestCase
     assert_select 'form select option[value=3]'
   end
 
+  test 'builder should allow passing include option to find collection' do
+    with_association_for @user, :company, :include => :city
+    assert_select 'form select.select#user_company_id'
+    assert_select 'form select option[value=1]'
+    assert_select 'form select option[value=2]'
+    assert_no_select 'form select option[value=3]'
+  end
+
+  test 'builder should allow passing joins option to find collection' do
+    with_association_for @user, :company, :joins => :city
+    assert_select 'form select.select#user_company_id'
+    assert_select 'form select option[value=2]'
+    assert_select 'form select option[value=3]'
+    assert_no_select 'form select option[value=1]'
+  end
+
   test 'builder should allow overriding collection to association input' do
     with_association_for @user, :company, :include_blank => false,
                          :collection => [Company.new(999, 'Teste')]

test/support/models.rb

@@ -8,6 +8,8 @@ class Company < Struct.new(:id, :name)
     all = (1..3).map{|i| Company.new(i, "Company #{i}")}
     return [all.first] if options[:conditions]
     return [all.last]  if options[:order]
+    return all[0..1] if options[:include]
+    return all[1..2] if options[:joins]
     all
   end
 end