Fix two has_one :through errors

* Set the association target on assignment;
* Reset target to nil on reset, rather than empty array.

Signed-off-by: Michael Koziarski <michael@koziarski.com>
[#895 state:committed]

activerecord/lib/active_record/associations.rb

@@ -1270,10 +1270,9 @@ module ActiveRecord
               association.create_through_record(new_value)
               self.send(reflection.name, new_value)
             else
-              association.replace(new_value)              
+              association.replace(new_value)
+              instance_variable_set(ivar, new_value.nil? ? nil : association)
             end
-
-            instance_variable_set(ivar, new_value.nil? ? nil : association)
           end
 
           define_method("set_#{reflection.name}_target") do |target|

activerecord/lib/active_record/associations/has_one_through_association.rb

@@ -22,6 +22,10 @@ module ActiveRecord
     
       def find_target
         super.first
+      end
+
+      def reset_target!
+        @target = nil
       end        
     end        
   end

activerecord/test/cases/associations/has_one_through_associations_test.rb

@@ -101,4 +101,13 @@ class HasOneThroughAssociationsTest < ActiveRecord::TestCase
     assert_equal clubs(:crazy_club), members[0].sponsor_club
   end
 
+  def test_uninitialized_has_one_through_should_return_nil_for_unsaved_record
+    assert_nil Member.new.club
+  end
+
+  def test_assigning_association_correctly_assigns_target
+    new_member = Member.create(:name => "Chris")
+    new_member.club = new_club = Club.create(:name => "LRUG")
+    assert_equal new_club, new_member.club.target
+  end
 end