Merge branch 'rm-take' into 4-1-stable

activerecord/lib/active_record/associations/collection_association.rb

@@ -129,6 +129,16 @@ def last(*args)
         first_nth_or_last(:last, *args)
       end
 
+      def take
+        if loaded?
+          target.first
+        else
+          scope.take.tap do |record|
+            set_inverse_instance record if record.is_a? ActiveRecord::Base
+          end
+        end
+      end
+
       def build(attributes = {}, &block)
         if attributes.is_a?(Array)
           attributes.collect { |attr| build(attr, &block) }

activerecord/lib/active_record/associations/collection_proxy.rb

@@ -227,6 +227,10 @@ def last(*args)
         @association.last(*args)
       end
 
+      def take
+        @association.take
+      end
+
       # Returns a new object of the collection type that has been instantiated
       # with +attributes+ and linked to this object, but have not yet been saved.
       # You can pass an array of attributes hashes, this will return an array

activerecord/test/cases/associations/has_many_associations_test.rb

@@ -33,6 +33,8 @@
 require 'models/tyre'
 require 'models/subscriber'
 require 'models/subscription'
+require 'models/zine'
+require 'models/interest'
 
 class HasManyAssociationsTestForReorderWithJoinDependency < ActiveRecord::TestCase
   fixtures :authors, :posts, :comments
@@ -97,7 +99,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   fixtures :accounts, :categories, :companies, :developers, :projects,
            :developers_projects, :topics, :authors, :comments,
            :posts, :readers, :taggings, :cars, :jobs, :tags,
-           :categorizations
+           :categorizations, :zines, :interests
 
   def setup
     Client.destroyed_client_ids.clear
@@ -435,6 +437,32 @@ def test_dynamic_find_should_respect_association_order
     assert_equal companies(:another_first_firm_client), companies(:first_firm).clients_sorted_desc.find_by_type('Client')
   end
 
+  def test_taking
+    posts(:other_by_bob).destroy
+    assert_equal posts(:misc_by_bob), authors(:bob).posts.take
+    assert_equal posts(:misc_by_bob), authors(:bob).posts.take!
+    authors(:bob).posts.to_a
+    assert_equal posts(:misc_by_bob), authors(:bob).posts.take
+    assert_equal posts(:misc_by_bob), authors(:bob).posts.take!
+  end
+
+  def test_taking_not_found
+    authors(:bob).posts.delete_all
+    assert_raise(ActiveRecord::RecordNotFound) { authors(:bob).posts.take! }
+    authors(:bob).posts.to_a
+    assert_raise(ActiveRecord::RecordNotFound) { authors(:bob).posts.take! }
+  end
+
+  def test_taking_with_inverse_of
+    interests(:woodsmanship).destroy
+    interests(:survival).destroy
+
+    zine = zines(:going_out)
+    interest = zine.interests.take
+    assert_equal interests(:hunting), interest
+    assert_same zine, interest.zine
+  end
+
   def test_cant_save_has_many_readonly_association
     authors(:david).readonly_comments.each { |c| assert_raise(ActiveRecord::ReadOnlyRecord) { c.save! } }
     authors(:david).readonly_comments.each { |c| assert c.readonly? }