result.txt

$ ruby test_custom_data.rb 
Loaded suite test_custom_data
Started
.F..
Finished in 0.018501 seconds.

  1) Failure:
test_creating_a_thing_with_a_foo(MyTest) [test_custom_data.rb:58]:
<"--- !ruby/object:Foo \nfirst: 1st\nsecond: 2nd\n"> expected but was
<#<Foo:0x1023a5ce8 @first="1st", @second="2nd">>.

4 tests, 5 assertions, 1 failures, 0 errors

test_custom_data.rb

require 'rubygems'
require 'test/unit'
require 'mongomapper'
require 'yaml'

MongoMapper.database = 'test_custom_data'


class Foo
  def initialize first, second
    @first, @second = first, second
  end

  def self.to_mongo(value)
    value ? YAML.dump(value) : nil
  end

  def self.from_mongo(value)
    value ? YAML.load(value) : nil
  end

  def to_s
    [@first, @second].join('-')
  end
end

class Thing
  include MongoMapper::Document
  key :title, String
  key :name, Foo
end


class MyTest < Test::Unit::TestCase
  def test_foo_is_serializable
    foo = Foo.new("1st", "2nd")
    assert_equal Foo.to_mongo(foo), YAML.dump(foo)
  end

  def test_foo_is_deserializable
    foo = Foo.new("1st", "2nd")
    as_yaml = YAML.dump(foo)
    assert_equal Foo.from_mongo(as_yaml).to_s, YAML.load(as_yaml).to_s
  end

  def test_creating_a_thing
    t = Time.now.to_s
    Thing.create(:title => t)
    assert_equal Thing.last.title, t
  end

  def test_creating_a_thing_with_a_foo
    foo = Foo.new("1st", "2nd")    
    t = Time.now.to_s
    Thing.create(:title => t, :name => foo)

    assert_equal Thing.last.title, t
    assert_equal Thing.last.name, foo
  end
end