cast hstore values on write to be consistent with reading from the db.

2 files changed, 12 insertions, 4 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
index 1be116ce10..58c6235059 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
@@ -6,10 +6,6 @@ module ActiveRecord
       module OID
         class Type
           def type; end
-
-          def type_cast_for_write(value)
-            value
-          end
         end
 
         class Identity < Type
@@ -224,6 +220,10 @@ module ActiveRecord
         end
 
         class Hstore < Type
+          def type_cast_for_write(value)
+            ConnectionAdapters::PostgreSQLColumn.hstore_to_string value
+          end
+
           def type_cast(value)
             return if value.nil?
 
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index 342d1b1433..5b9453a579 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -129,6 +129,14 @@ module ActiveRecord
         end
       end
 
+      def type_cast_for_write(value)
+        if @oid_type.respond_to?(:type_cast_for_write)
+          @oid_type.type_cast_for_write(value)
+        else
+          super
+        end
+      end
+
       def type_cast(value)
         return if value.nil?
         return super if encoded?