Fix problem with loading polymorphic associations which have been defined in an abstract superclass. Fixes #552.

2 files changed, 22 insertions, 8 deletions

diff --git a/activerecord/lib/active_record/associations/association_scope.rb b/activerecord/lib/active_record/associations/association_scope.rb
index ab102b2b8f..94847bc2ae 100644
--- a/activerecord/lib/active_record/associations/association_scope.rb
+++ b/activerecord/lib/active_record/associations/association_scope.rb
@@ -75,10 +75,16 @@ module ActiveRecord
             foreign_key = reflection.active_record_primary_key
           end
 
+          conditions = self.conditions[i]
+
           if reflection == chain.last
             scope = scope.where(table[key].eq(owner[foreign_key]))
 
-            conditions[i].each do |condition|
+            if reflection.type
+              scope = scope.where(table[reflection.type].eq(owner.class.base_class.name))
+            end
+
+            conditions.each do |condition|
               if options[:through] && condition.is_a?(Hash)
                 condition = { table.name => condition }
               end
@@ -87,12 +93,16 @@ module ActiveRecord
             end
           else
             constraint = table[key].eq(foreign_table[foreign_key])
-            join       = join(foreign_table, constraint)
 
-            scope = scope.joins(join)
+            if reflection.type
+              type = chain[i + 1].klass.base_class.name
+              constraint = constraint.and(table[reflection.type].eq(type))
+            end
+
+            scope = scope.joins(join(foreign_table, constraint))
 
-            unless conditions[i].empty?
-              scope = scope.where(sanitize(conditions[i], table))
+            unless conditions.empty?
+              scope = scope.where(sanitize(conditions, table))
             end
           end
         end
diff --git a/activerecord/lib/active_record/associations/join_dependency/join_association.rb b/activerecord/lib/active_record/associations/join_dependency/join_association.rb
index c32753782f..03963ab060 100644
--- a/activerecord/lib/active_record/associations/join_dependency/join_association.rb
+++ b/activerecord/lib/active_record/associations/join_dependency/join_association.rb
@@ -62,6 +62,7 @@ module ActiveRecord
         def join_to(relation)
           tables        = @tables.dup
           foreign_table = parent_table
+          foreign_klass = parent.active_record
 
           # The chain starts with the target table, but we want to end with it here (makes
           # more sense in this context), so we reverse
@@ -91,14 +92,17 @@ module ActiveRecord
 
             constraint = build_constraint(reflection, table, key, foreign_table, foreign_key)
 
-            unless conditions[i].empty?
-              constraint = constraint.and(sanitize(conditions[i], table))
+            conditions = self.conditions[i].dup
+            conditions << { reflection.type => foreign_klass.base_class.name } if reflection.type
+
+            unless conditions.empty?
+              constraint = constraint.and(sanitize(conditions, table))
             end
 
             relation.from(join(table, constraint))
 
             # The current table in this iteration becomes the foreign table in the next
-            foreign_table = table
+            foreign_table, foreign_klass = table, reflection.klass
           end
 
           relation