```ruby
require 'spec_helper'

describe RailsAdmin::Config::Fields::Types::Uuid do
  let(:uuid) { SecureRandom.uuid }

  before do
    RailsAdmin.config do |config|
      config.model FieldTest do
        field :uuid_field, :uuid
      end
    end

    @object = FactoryGirl.create(:field_test)
    @object.stub(:uuid_field).and_return uuid

    @field = RailsAdmin.config(FieldTest).fields.detect { |f| f.name == :uuid_field }
    @field.bindings = {object: @object}
  end

  it 'field is a Uuid fieldtype' do
    expect(@field.class).to eq RailsAdmin::Config::Fields::Types::Uuid
  end

  it 'handles uuid string' do
    expect(@field.value).to eq uuid
  end

  it_behaves_like 'a generic field type', :string_field, :uuid
end
```

Replace old stub syntax with newest RSpec 3
user
```ruby
require 'spec_helper'

describe RailsAdmin::Config::Fields::Types::Uuid do
  let(:uuid) { SecureRandom.uuid }
  let(:object) { FactoryGirl.create(:field_test) }
  let(:field) { RailsAdmin.config(FieldTest).fields.detect { |f| f.name == :uuid_field } }

  before do
    RailsAdmin.config do |config|
      config.model FieldTest do
        field :uuid_field, :uuid
      end
    end

    allow(object).to receive(:uuid_field).and_return uuid
    field.bindings = {object: object}
  end

  it 'field is a Uuid fieldtype' do
    expect(field.class).to eq RailsAdmin::Config::Fields::Types::Uuid
  end

  it 'handles uuid string' do
    expect(field.value).to eq uuid
  end

  it_behaves_like 'a generic field type', :string_field, :uuid
end
```
assistant