Prefactory

The ease and fidelity of factories with the performance of static fixtures.

Prefactory allows you to create factory objects and perform other expensive ActiveRecord operations in RSpec before(:all) blocks, transparently wrapping example groups in nested transactions to automatically roll back any data changes that occur during a specific test, while also ensuring after-commit callbacks are executed for the synthetic commits.

Requirements

• ActiveRecord >= 4
• RSpec
• FactoryGirl
• A database for which ActiveRecord supports nested transactions (e.g. MySQL, Postgresql)

Installation

Add the gem to the :test group in your Rails application's Gemfile:

group :test do
  gem 'prefactory'
end

Add this to your RSpec spec_helper.rb

RSpec.configure do |config|
  config.include Prefactory

  # ensure Rails' transaction fixtures are disabled
  config.use_transactional_fixtures = false

  # optional, to enable shorthand creation
  # using only Factory name (see examples, below)
  config.include FactoryGirl::Syntax::Methods
end

Example Usage

describe User do
  before :all do   # executes once

    # invokes FactoryGirl.create(:user)
    # reference object as 'friend' in tests
    prefactory_add(:friend) { FactoryGirl.create :user }

    # invokes create(:user) if available, e.g
    # if rspec is configured with:
    #   config.include FactoryGirl::Syntax::Methods
    # reference object as 'user' in examples
    prefactory_add :user

  end

  # convenience method, equivalent to:
  # before(:all) do
  #   prefactory_add(:other_friend) do
  #     create :user
  #   end
  # end
  set!(:other_friend) { create :user }

  context 'a new user' do

    it { expect(user.friends.count).to eq 0 }

    context 'with a friend' do
      before(:all) { user.add_friend(friend) }   # executes once

      it { expect(user.friends.count).to eq 1 }

      # these changes will be transparently rolled back
      it "allows removing the friend" do
        expect { user.remove_friend(friend) }.to_not raise_error
        expect(user.friends.count).to eq 0
      end

      it "disallows adding the same friend again" do
        expect { user.add_friend(friend) }.to raise_error
        expect(user.friends.count).to eq 1
      end

      # these changes will be transparently rolled back
      it "allows adding a different friend" do
        expect { user.add_friend(other_friend) }.to_not raise_error
        expect(user.friends.count).to eq 2
      end

      it { expect(user.friends).to include friend }
      it { expect(user.friends).not_to include other_friend }
    end
  end
end

See also: An example rails application with Prefactory configured

If desired, it is also possible to only include the set! method and related lookup functionality for e.g. specs that cannot use transactional isolation (like some threaded Capybara feature specs, or similar):

RSpec.configure do |config|
  config.include Prefactory::Lookups
end

Contributing

1. Fork it ( http://github.com/socialcast/prefactory/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a pull request

Copyright

Copyright (c) 2012-2014 VMware, Inc. All Rights Reserved. Released under the terms of the MIT license. See LICENSE for details.