```ruby
# coding:utf-8

require_relative '../test_helper'

module SmartAnswer
  class MoneyTest < ActiveSupport::TestCase
    test "Can compare money with money" do
      two = Money.new("2")
      assert Money.new("2") == two
      assert Money.new("3") > two
      assert Money.new("1") < two
    end

    test "Can compare money with number" do
      m = Money.new("520")
      assert m == 520
      assert m > 1
      assert m < 1000
    end

    test "Money with spaces or commas gets parsed correctly" do
      one = Money.new("1,000")
      assert one == 1000

      two = Money.new("2 000")
      assert two == 2000
    end

    test "should be possible to initialize with a BigDecimal" do
      v = BigDecimal.new("1234.5678")
      money = Money.new(v)
      assert_equal "1234.5678", money.to_s
    end
  end
end
```

Add illustrative test around Money object
user
```ruby
# coding:utf-8

require_relative '../test_helper'

module SmartAnswer
  class MoneyTest < ActiveSupport::TestCase
    test "Can compare money with money" do
      two = Money.new("2")
      assert Money.new("2") == two
      assert Money.new("3") > two
      assert Money.new("1") < two
    end

    test "Can compare money with number" do
      m = Money.new("520")
      assert m == 520
      assert m > 1
      assert m < 1000
    end

    test "Money with spaces or commas gets parsed correctly" do
      one = Money.new("1,000")
      assert one == 1000

      two = Money.new("2 000")
      assert two == 2000
    end

    test "should be possible to initialize with a BigDecimal" do
      v = BigDecimal.new("1234.5678")
      money = Money.new(v)
      assert_equal "1234.5678", money.to_s
    end

    test 'should not accept negative numbers' do
      assert_raises(SmartAnswer::InvalidResponse) do
        Money.new('-1')
      end
    end
  end
end
```
assistant