spec.log

$ ruby spec.rb 
 ~ (0.000990) SET backslash_quote = off
 ~ (0.019931) SET standard_conforming_strings = on
 ~ (0.000291) SET client_min_messages = warning
 ~ (0.021172) SELECT current_schema()
 ~ (0.021269) SELECT COUNT(*) FROM "information_schema"."tables" WHERE "table_type" = 'BASE TABLE' AND "table_schema" = 'public' AND "table_name" = 'test_dms'
 ~ (0.001382) SELECT COUNT(*) FROM "information_schema"."tables" WHERE "table_type" = 'BASE TABLE' AND "table_schema" = 'public' AND "table_name" = 'testings'
 ~ (0.001239) SELECT COUNT(*) FROM "information_schema"."tables" WHERE "table_type" = 'BASE TABLE' AND "table_schema" = 'public' AND "table_name" = 'tests'
 ~ (0.010847) SELECT version()
 ~ (0.000127) SET client_min_messages = warning
 ~ (0.000418) DROP TABLE IF EXISTS "test_dms"
 ~ (0.000226) RESET client_min_messages
 ~ (0.000143) SET client_min_messages = warning
 ~ (0.001449) SELECT COUNT(*) FROM "information_schema"."tables" WHERE "table_type" = 'BASE TABLE' AND "table_schema" = 'public' AND "table_name" = 'test_dms'
 ~ (0.254778) CREATE TABLE "test_dms" ("id" SERIAL NOT NULL, "created_at" TIMESTAMP, "created_on" DATE, "updated_at" TIMESTAMP, "updated_on" DATE, PRIMARY KEY("id"))
 ~ (0.000447) RESET client_min_messages
 ~ (0.000189) SET client_min_messages = warning
 ~ (0.000241) DROP TABLE IF EXISTS "testings"
 ~ (0.000149) RESET client_min_messages
 ~ (0.000151) SET client_min_messages = warning
 ~ (0.002086) SELECT COUNT(*) FROM "information_schema"."tables" WHERE "table_type" = 'BASE TABLE' AND "table_schema" = 'public' AND "table_name" = 'testings'
 ~ (0.003325) CREATE TABLE "testings" ("test_dm_id" INTEGER NOT NULL, "test_id" INTEGER NOT NULL, PRIMARY KEY("test_dm_id", "test_id"))
 ~ (0.001733) CREATE INDEX "index_testings_test" ON "testings" ("test_id")
 ~ (0.001475) CREATE INDEX "index_testings_test_dm" ON "testings" ("test_dm_id")
 ~ (0.000244) RESET client_min_messages
 ~ (0.000318) SET client_min_messages = warning
 ~ (0.000130) DROP TABLE IF EXISTS "tests"
 ~ (0.000166) RESET client_min_messages
 ~ (0.000095) SET client_min_messages = warning
 ~ (0.001461) SELECT COUNT(*) FROM "information_schema"."tables" WHERE "table_type" = 'BASE TABLE' AND "table_schema" = 'public' AND "table_name" = 'tests'
 ~ (0.003135) CREATE TABLE "tests" ("id" SERIAL NOT NULL, PRIMARY KEY("id"))
 ~ (0.000210) RESET client_min_messages
 ~ (0.003759) SELECT COUNT(*) FROM "information_schema"."table_constraints" WHERE "constraint_type" = 'FOREIGN KEY' AND "table_schema" = 'public' AND "table_name" = 'testings' AND "constraint_name" = 'testings_test_dm_fk'
 ~ (0.036113) ALTER TABLE "testings" ADD CONSTRAINT "testings_test_dm_fk" FOREIGN KEY ("test_dm_id") REFERENCES "test_dms" ("id") ON DELETE NO ACTION ON UPDATE NO ACTION
 ~ (0.003150) SELECT COUNT(*) FROM "information_schema"."table_constraints" WHERE "constraint_type" = 'FOREIGN KEY' AND "table_schema" = 'public' AND "table_name" = 'testings' AND "constraint_name" = 'testings_test_fk'
 ~ (0.002098) ALTER TABLE "testings" ADD CONSTRAINT "testings_test_fk" FOREIGN KEY ("test_id") REFERENCES "tests" ("id") ON DELETE NO ACTION ON UPDATE NO ACTION
 ~ (0.012370) INSERT INTO "tests" DEFAULT VALUES RETURNING "id"
 ~ (0.000711) INSERT INTO "tests" DEFAULT VALUES RETURNING "id"
spec.rb:40:in `dump': can't dump hash with default proc (TypeError)
	from spec.rb:40

spec.rb

# Trying to replicate http://datamapper.lighthouseapp.com/projects/20609-datamapper/tickets/470-memcaching-can-t-marshal-dm-objects#ticket-470-19
require 'rubygems'
require 'data_mapper'
#require 'dm-core'
#require 'dm-migrations'
#require 'dm-timestamps'

DataMapper::Logger.new($stdout, :debug)
DataMapper.setup(:default, 'postgres://test:test@localhost/test') # createdb test

class TestDm
  include DataMapper::Resource

  property :id, Serial
  property :created_at, DateTime 
  property :created_on, Date 
  property :updated_at, DateTime
  property :updated_on, Date

  has n, :tests, :through => :testing 
  has n, :testing
end

class Testing
  include DataMapper::Resource
   belongs_to :test_dm, :key => true
   belongs_to :test, :key => true
end
class Test
  include DataMapper::Resource
  property :id, Serial
  has n, :testing
end

DataMapper.finalize
DataMapper.auto_migrate!
test = Test.create.tap do |t|
  t.testing.create(:test => Test.create)
end
puts Marshal.load(Marshal.dump(test)).inspect