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

activerecord/CHANGELOG.md

@@ -1,3 +1,18 @@
*   Type cast hstore values on write, so that the value is consistent
    with reading from the database.

    Example:

        x = Hstore.new tags: {"bool" => true, "number" => 5}

        # Before:
        x.tags # => {"bool" => true, "number" => 5}

        # After:
        x.tags # => {"bool" => "true", "number" => "5"}

    *Yves Senn* , *Severin Schoepke*

*   Fix multidimensional PG arrays containing non-string items.

    *Yves Senn*

activerecord/lib/active_record/connection_adapters/postgresql/oid.rb

@@ -6,10 +6,6 @@ class PostgreSQLAdapter < AbstractAdapter
      module OID
        class Type
          def type; end

          def type_cast_for_write(value)
            value
          end
        end

        class Identity < Type
@@ -224,6 +220,10 @@ def type_cast(value)
        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?

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -129,6 +129,14 @@ def self.extract_value_from_default(default)
        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?

activerecord/test/cases/adapters/postgresql/hstore_test.rb

@@ -70,6 +70,13 @@ def test_change_table_supports_hstore
    Hstore.reset_column_information
  end

  def test_cast_value_on_write
    x = Hstore.new tags: {"bool" => true, "number" => 5}
    assert_equal({"bool" => "true", "number" => "5"}, x.tags)
    x.save
    assert_equal({"bool" => "true", "number" => "5"}, x.reload.tags)
  end

  def test_type_cast_hstore
    assert @column