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

1 files changed, 7 insertions, 3 deletions

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