Remove warning by using a custom coder

The native JSON library bypasses the `to_json` overrides in
active_support/core_ext/object/to_json.rb by calling its native
implementation directly. However `ActiveRecord::Store` uses a
HWIA so `JSON.dump` will call our `to_json` instead with a
`State` object for options rather than a `Hash`. This generates
a warning when the `:encoding`, `:only` & `:except` keys are
accessed in `Hash#as_json` because the `State` object delegates
unknown keys to `instance_variable_get` in its `:[]` method.

Workaround this warning in the test by using a custom coder that
calls `ActiveSupport::JSON.encode` directly.

1 files changed, 16 insertions, 2 deletions

diff --git a/activerecord/test/models/admin/user.rb b/activerecord/test/models/admin/user.rb
index 467f3ccd39..024fede266 100644
--- a/activerecord/test/models/admin/user.rb
+++ b/activerecord/test/models/admin/user.rb
@@ -1,10 +1,24 @@
 class Admin::User < ActiveRecord::Base
+  class Coder
+    def initialize(default = {})
+      @default = default
+    end
+
+    def dump(o)
+      ActiveSupport::JSON.encode(o || @default)
+    end
+
+    def load(s)
+      s.present? ? ActiveSupport::JSON.decode(s) : @default.clone
+    end
+  end
+
   belongs_to :account
   store :settings, :accessors => [ :color, :homepage ]
   store_accessor :settings, :favorite_food
   store :preferences, :accessors => [ :remember_login ]
-  store :json_data, :accessors => [ :height, :weight ], :coder => JSON
-  store :json_data_empty, :accessors => [ :is_a_good_guy ], :coder => JSON
+  store :json_data, :accessors => [ :height, :weight ], :coder => Coder.new
+  store :json_data_empty, :accessors => [ :is_a_good_guy ], :coder => Coder.new
 
   def phone_number
     read_store_attribute(:settings, :phone_number).gsub(/(\d{3})(\d{3})(\d{4})/,'(\1) \2-\3')