Add support scopes to be used in associations.

lib/simple_form/form_builder.rb

@@ -449,22 +449,26 @@ module SimpleForm
 
     private
 
-    def fetch_association_collection(reflection, options)
+    def fetch_association_collection(reflection, options) #:nodoc:
       options.fetch(:collection) do
-        conditions = reflection.options[:conditions]
-        conditions = object.instance_exec(&conditions) if conditions.respond_to?(:call)
+        relation = reflection.klass.all
 
-        relation = reflection.klass.where(conditions)
-
-        if relation.respond_to?(:order)
-          relation.order(reflection.options[:order])
+        if reflection.respond_to?(:scope) && reflection.scope
+          relation = reflection.klass.instance_exec(&reflection.scope)
         else
-          relation
+          order = reflection.options[:order]
+          conditions = reflection.options[:conditions]
+          conditions = object.instance_exec(&conditions) if conditions.respond_to?(:call)
+
+          relation = relation.where(conditions)
+          relation = relation.order(order) if relation.respond_to?(:order)
         end
+
+        relation
       end
     end
 
-    def build_association_attribute(reflection, association, options)
+    def build_association_attribute(reflection, association, options) #:nodoc:
       case reflection.macro
       when :belongs_to
         (reflection.respond_to?(:options) && reflection.options[:foreign_key]) || :"#{reflection.name}_id"

test/form_builder/association_test.rb

@@ -113,6 +113,14 @@ class AssociationTest < ActionView::TestCase
     assert_no_select 'form select option[value=3]'
   end
 
+  test 'builder allows collection to have a scope' do
+    with_association_for @user, :special_pictures
+    assert_select 'form select.select#user_special_picture_ids'
+    assert_select 'form select option[value=3]', '3'
+    assert_no_select 'form select option[value=1]'
+    assert_no_select 'form select option[value=2]'
+  end
+
   test 'builder marks the record which already belongs to the user' do
     @user.company_id = 2
     with_association_for @user, :company, as: :radio_buttons

test/support/models.rb

@@ -23,21 +23,17 @@ Picture = Struct.new(:id, :name) do
   extend ActiveModel::Naming
   include ActiveModel::Conversion
 
-  class << self
-    delegate :where, to: :_relation
-  end
-
-  def self._relation
-    all
+  def self.where(conditions = nil)
+    if conditions.is_a?(Hash) && conditions[:name]
+      all.to_a.last
+    else
+      all
+    end
   end
 
   def self.all
     Relation.new((1..3).map { |i| new(i, "#{name} #{i}") })
   end
-
-  def persisted?
-    true
-  end
 end
 
 Company = Struct.new(:id, :name) do
@@ -74,7 +70,8 @@ class User
     :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, :action, :credit_card, :gender,
-    :extra_special_company_id, :pictures, :picture_ids
+    :extra_special_company_id, :pictures, :picture_ids, :special_pictures,
+    :special_picture_ids
 
   def self.build(extra_attributes = {})
     attributes = {
@@ -156,6 +153,8 @@ class User
         Association.new(Company, association, :belongs_to, nil, { conditions: proc { { id: self.id } } })
       when :pictures
         Association.new(Picture, association, :has_many, nil, {})
+      when :special_pictures
+        Association.new(Picture, association, :has_many, proc { where(name: self.name) }, {})
     end
   end