1 files changed, 29 insertions, 20 deletions

diff --git a/activerecord/lib/active_record/associations/association.rb b/activerecord/lib/active_record/associations/association.rb
index 729ef8c55a..67ea489b22 100644
--- a/activerecord/lib/active_record/associations/association.rb
+++ b/activerecord/lib/active_record/associations/association.rb
@@ -13,11 +13,11 @@ module ActiveRecord
     #       BelongsToAssociation
     #         BelongsToPolymorphicAssociation
     #     CollectionAssociation
-    #       HasAndBelongsToManyAssociation
     #       HasManyAssociation
     #         HasManyThroughAssociation + ThroughAssociation
     class Association #:nodoc:
       attr_reader :owner, :target, :reflection
+      attr_accessor :inversed
 
       delegate :options, :to => :reflection
 
@@ -30,7 +30,7 @@ module ActiveRecord
         reset_scope
       end
 
-      # Returns the name of the table of the related class:
+      # Returns the name of the table of the associated class:
       #
       #   post.comments.aliased_table_name # => "comments"
       #
@@ -43,6 +43,7 @@ module ActiveRecord
         @loaded = false
         @target = nil
         @stale_state = nil
+        @inversed = false
       end
 
       # Reloads the \target and returns +self+ on success.
@@ -60,18 +61,19 @@ module ActiveRecord
 
       # Asserts the \target has been loaded setting the \loaded flag to +true+.
       def loaded!
-        @loaded      = true
+        @loaded = true
         @stale_state = stale_state
+        @inversed = false
       end
 
       # The target is stale if the target no longer points to the record(s) that the
       # relevant foreign_key(s) refers to. If stale, the association accessor method
       # on the owner will reload the target. It's up to subclasses to implement the
-      # state_state method if relevant.
+      # stale_state method if relevant.
       #
       # Note that if the target has not been loaded, it is not considered stale.
       def stale_target?
-        loaded? && @stale_state != stale_state
+        !inversed && loaded? && @stale_state != stale_state
       end
 
       # Sets the target of this association to <tt>\target</tt>, and the \loaded flag to +true+.
@@ -84,11 +86,6 @@ module ActiveRecord
         target_scope.merge(association_scope)
       end
 
-      def scoped
-        ActiveSupport::Deprecation.warn "#scoped is deprecated. use #scope instead."
-        scope
-      end
-
       # The scope for this association.
       #
       # Note that the association_scope is merged into the target_scope only when the
@@ -107,10 +104,12 @@ module ActiveRecord
 
       # Set the inverse association, if possible
       def set_inverse_instance(record)
-        if record && invertible_for?(record)
+        if invertible_for?(record)
           inverse = record.association(inverse_reflection_for(record).name)
           inverse.target = owner
+          inverse.inversed = true
         end
+        record
       end
 
       # Returns the class of the target. belongs_to polymorphic overrides this to look at the
@@ -122,7 +121,7 @@ module ActiveRecord
       # Can be overridden (i.e. in ThroughAssociation) to merge in other scopes (i.e. the
       # through association's scope)
       def target_scope
-        klass.all
+        AssociationRelation.create(klass, klass.arel_table, self).merge!(klass.all)
       end
 
       # Loads the \target if needed and returns it.
@@ -164,6 +163,13 @@ module ActiveRecord
         @reflection = @owner.class.reflect_on_association(reflection_name)
       end
 
+      def initialize_attributes(record) #:nodoc:
+        skip_assign = [reflection.foreign_key, reflection.type].compact
+        attributes = create_scope.except(*(record.changed - skip_assign))
+        record.assign_attributes(attributes)
+        set_inverse_instance(record)
+      end
+
       private
 
         def find_target?
@@ -189,13 +195,14 @@ module ActiveRecord
           creation_attributes.each { |key, value| record[key] = value }
         end
 
-        # Should be true if there is a foreign key present on the owner which
+        # Returns true if there is a foreign key present on the owner which
         # references the target. This is used to determine whether we can load
         # the target if the owner is currently a new record (and therefore
-        # without a key).
+        # without a key). If the owner is a new record then foreign_key must
+        # be present in order to load target.
         #
         # Currently implemented by belongs_to (vanilla and polymorphic) and
-        # has_one/has_many :through associations which go through a belongs_to
+        # has_one/has_many :through associations which go through a belongs_to.
         def foreign_key_present?
           false
         end
@@ -220,7 +227,12 @@ module ActiveRecord
         # Returns true if inverse association on the given record needs to be set.
         # This method is redefined by subclasses.
         def invertible_for?(record)
-          inverse_reflection_for(record)
+          foreign_key_for?(record) && inverse_reflection_for(record)
+        end
+
+        # Returns true if record contains the foreign_key
+        def foreign_key_for?(record)
+          record.attributes.has_key? reflection.foreign_key
         end
 
         # This should be implemented to return the values of the relevant key(s) on the owner,
@@ -233,10 +245,7 @@ module ActiveRecord
 
         def build_record(attributes)
           reflection.build_association(attributes) do |record|
-            skip_assign = [reflection.foreign_key, reflection.type].compact
-            attributes = create_scope.except(*(record.changed - skip_assign))
-            record.assign_attributes(attributes)
-            set_inverse_instance(record)
+            initialize_attributes(record)
           end
         end
     end