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1207 lines
29 KiB
Markdown
1207 lines
29 KiB
Markdown
Getting Started
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===============
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Update Your Gemfile
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-------------------
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If you're using Rails, you'll need to change the required version of `factory_girl_rails`:
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```ruby
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gem "factory_girl_rails", "~> 4.0"
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```
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If you're *not* using Rails, you'll just have to change the required version of `factory_girl`:
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```ruby
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gem "factory_girl", "~> 4.0"
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```
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JRuby users: factory_girl works with JRuby starting with 1.6.7.2 (latest stable, as per July 2012).
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JRuby has to be used in 1.9 mode, for that, use JRUBY_OPTS environment variable:
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```bash
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export JRUBY_OPTS=--1.9
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```
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Once your Gemfile is updated, you'll want to update your bundle.
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Configure your test suite
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-------------------------
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```ruby
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# rspec
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RSpec.configure do |config|
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config.include FactoryGirl::Syntax::Methods
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end
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# Test::Unit
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class Test::Unit::TestCase
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include FactoryGirl::Syntax::Methods
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end
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# Cucumber
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World(FactoryGirl::Syntax::Methods)
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# Spinach
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class Spinach::FeatureSteps
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include FactoryGirl::Syntax::Methods
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end
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# MiniTest
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class MiniTest::Unit::TestCase
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include FactoryGirl::Syntax::Methods
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end
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# MiniTest::Spec
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class MiniTest::Spec
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include FactoryGirl::Syntax::Methods
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end
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# minitest-rails
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class MiniTest::Rails::ActiveSupport::TestCase
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include FactoryGirl::Syntax::Methods
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end
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```
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If you do not include `FactoryGirl::Syntax::Methods` in your test suite, then all factory_girl methods will need to be prefaced with `FactoryGirl`.
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Linting Factories
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-----------------
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factory_girl allows for linting known factories:
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```ruby
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FactoryGirl.lint
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```
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`FactoryGirl.lint` builds each factory and subsequently calls `#valid?` on it
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(if `#valid?` is defined); if any calls to `#valid?` return `false`,
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`FactoryGirl::InvalidFactoryError` is raised with a list of the offending
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factories. Recommended usage of `FactoryGirl.lint` is to invoke this once
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before the test suite is run.
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With RSpec:
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```ruby
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# spec/support/factory_girl.rb
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RSpec.configure do |config|
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# additional factory_girl configuration
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config.before(:suite) do
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FactoryGirl.lint
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end
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end
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```
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Defining factories
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------------------
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Each factory has a name and a set of attributes. The name is used to guess the class of the object by default, but it's possible to explicitly specify it:
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```ruby
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# This will guess the User class
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FactoryGirl.define do
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factory :user do
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first_name "John"
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last_name "Doe"
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admin false
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end
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# This will use the User class (Admin would have been guessed)
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factory :admin, class: User do
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first_name "Admin"
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last_name "User"
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admin true
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end
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end
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```
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It is highly recommended that you have one factory for each class that provides the simplest set of attributes necessary to create an instance of that class. If you're creating ActiveRecord objects, that means that you should only provide attributes that are required through validations and that do not have defaults. Other factories can be created through inheritance to cover common scenarios for each class.
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Attempting to define multiple factories with the same name will raise an error.
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Factories can be defined anywhere, but will be automatically loaded if they
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are defined in files at the following locations:
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test/factories.rb
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spec/factories.rb
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test/factories/*.rb
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spec/factories/*.rb
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Using factories
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---------------
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factory\_girl supports several different build strategies: build, create, attributes\_for and build\_stubbed:
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```ruby
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# Returns a User instance that's not saved
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user = build(:user)
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# Returns a saved User instance
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user = create(:user)
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# Returns a hash of attributes that can be used to build a User instance
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attrs = attributes_for(:user)
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# Returns an object with all defined attributes stubbed out
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stub = build_stubbed(:user)
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# Passing a block to any of the methods above will yield the return object
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create(:user) do |user|
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user.posts.create(attributes_for(:post))
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end
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```
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No matter which strategy is used, it's possible to override the defined attributes by passing a hash:
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```ruby
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# Build a User instance and override the first_name property
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user = build(:user, first_name: "Joe")
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user.first_name
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# => "Joe"
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```
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Lazy Attributes
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---------------
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Most factory attributes can be added using static values that are evaluated when
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the factory is defined, but some attributes (such as associations and other
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attributes that must be dynamically generated) will need values assigned each
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time an instance is generated. These "lazy" attributes can be added by passing a
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block instead of a parameter:
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```ruby
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factory :user do
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# ...
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activation_code { User.generate_activation_code }
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date_of_birth { 21.years.ago }
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end
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```
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Aliases
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-------
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Aliases allow you to use named associations more easily.
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```ruby
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factory :user, aliases: [:author, :commenter] do
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first_name "John"
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last_name "Doe"
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date_of_birth { 18.years.ago }
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end
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factory :post do
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author
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# instead of
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# association :author, factory: :user
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title "How to read a book effectively"
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body "There are five steps involved."
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end
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factory :comment do
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commenter
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# instead of
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# association :commenter, factory: :user
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body "Great article!"
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end
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```
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Dependent Attributes
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--------------------
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Attributes can be based on the values of other attributes using the evaluator that is yielded to lazy attribute blocks:
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```ruby
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factory :user do
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first_name "Joe"
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last_name "Blow"
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email { "#{first_name}.#{last_name}@example.com".downcase }
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end
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create(:user, last_name: "Doe").email
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# => "joe.doe@example.com"
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```
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Transient Attributes
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--------------------
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There may be times where your code can be DRYed up by passing in transient attributes to factories.
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```ruby
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factory :user do
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ignore do
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rockstar true
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upcased false
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end
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name { "John Doe#{" - Rockstar" if rockstar}" }
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email { "#{name.downcase}@example.com" }
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after(:create) do |user, evaluator|
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user.name.upcase! if evaluator.upcased
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end
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end
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create(:user, upcased: true).name
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#=> "JOHN DOE - ROCKSTAR"
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```
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Static and dynamic attributes can be ignored. Ignored attributes will be ignored
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within attributes\_for and won't be set on the model, even if the attribute
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exists or you attempt to override it.
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Within factory_girl's dynamic attributes, you can access ignored attributes as
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you would expect. If you need to access the evaluator in a factory_girl callback,
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you'll need to declare a second block argument (for the evaluator) and access
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ignored attributes from there.
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Associations
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------------
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It's possible to set up associations within factories. If the factory name is the same as the association name, the factory name can be left out.
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```ruby
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factory :post do
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# ...
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author
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end
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```
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You can also specify a different factory or override attributes:
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```ruby
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factory :post do
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# ...
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association :author, factory: :user, last_name: "Writely"
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end
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```
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The behavior of the association method varies depending on the build strategy used for the parent object.
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```ruby
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# Builds and saves a User and a Post
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post = create(:post)
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post.new_record? # => false
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post.author.new_record? # => false
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# Builds and saves a User, and then builds but does not save a Post
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post = build(:post)
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post.new_record? # => true
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post.author.new_record? # => false
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```
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To not save the associated object, specify strategy: :build in the factory:
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```ruby
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factory :post do
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# ...
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association :author, factory: :user, strategy: :build
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end
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# Builds a User, and then builds a Post, but does not save either
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post = build(:post)
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post.new_record? # => true
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post.author.new_record? # => true
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```
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Please note that the `strategy: :build` option must be passed to an explicit call to `association`,
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and cannot be used with implicit associations:
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```ruby
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factory :post do
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# ...
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author strategy: :build # <<< this does *not* work; causes author_id to be nil
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```
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Generating data for a `has_many` relationship is a bit more involved,
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depending on the amount of flexibility desired, but here's a surefire example
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of generating associated data.
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```ruby
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FactoryGirl.define do
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# post factory with a `belongs_to` association for the user
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factory :post do
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title "Through the Looking Glass"
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user
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end
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# user factory without associated posts
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factory :user do
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name "John Doe"
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# user_with_posts will create post data after the user has been created
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factory :user_with_posts do
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# posts_count is declared as an ignored attribute and available in
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# attributes on the factory, as well as the callback via the evaluator
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ignore do
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posts_count 5
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end
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# the after(:create) yields two values; the user instance itself and the
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# evaluator, which stores all values from the factory, including ignored
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# attributes; `create_list`'s second argument is the number of records
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# to create and we make sure the user is associated properly to the post
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after(:create) do |user, evaluator|
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create_list(:post, evaluator.posts_count, user: user)
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end
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end
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end
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end
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```
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This allows us to do:
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```ruby
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create(:user).posts.length # 0
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create(:user_with_posts).posts.length # 5
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create(:user_with_posts, posts_count: 15).posts.length # 15
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```
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Inheritance
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-----------
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You can easily create multiple factories for the same class without repeating common attributes by nesting factories:
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```ruby
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factory :post do
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title "A title"
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factory :approved_post do
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approved true
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end
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end
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approved_post = create(:approved_post)
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approved_post.title # => "A title"
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approved_post.approved # => true
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```
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You can also assign the parent explicitly:
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```ruby
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factory :post do
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title "A title"
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end
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factory :approved_post, parent: :post do
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approved true
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end
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```
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As mentioned above, it's good practice to define a basic factory for each class
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with only the attributes required to create it. Then, create more specific
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factories that inherit from this basic parent. Factory definitions are still
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code, so keep them DRY.
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Sequences
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---------
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Unique values in a specific format (for example, e-mail addresses) can be
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generated using sequences. Sequences are defined by calling sequence in a
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definition block, and values in a sequence are generated by calling
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`generate`:
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```ruby
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# Defines a new sequence
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FactoryGirl.define do
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sequence :email do |n|
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"person#{n}@example.com"
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end
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end
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generate :email
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# => "person1@example.com"
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generate :email
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# => "person2@example.com"
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```
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Sequences can be used as attributes:
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```ruby
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factory :user do
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email
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end
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```
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Or in lazy attributes:
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```ruby
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factory :invite do
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invitee { generate(:email) }
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end
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```
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And it's also possible to define an in-line sequence that is only used in
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a particular factory:
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```ruby
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factory :user do
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sequence(:email) { |n| "person#{n}@example.com" }
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end
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```
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You can also override the initial value:
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```ruby
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factory :user do
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sequence(:email, 1000) { |n| "person#{n}@example.com" }
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end
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```
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Without a block, the value will increment itself, starting at its initial value:
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```ruby
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factory :post do
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sequence(:position)
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end
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```
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Sequences can also have aliases. The sequence aliases share the same counter:
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```ruby
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factory :user do
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sequence(:email, 1000, aliases: [:sender, :receiver]) { |n| "person#{n}@example.com" }
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end
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# will increase value counter for :email which is shared by :sender and :receiver
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generate(:sender)
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```
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Define aliases and use default value (1) for the counter
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```ruby
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factory :user do
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sequence(:email, aliases: [:sender, :receiver]) { |n| "person#{n}@example.com" }
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end
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```
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Setting the value:
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```ruby
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factory :user do
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sequence(:email, 'a', aliases: [:sender, :receiver]) { |n| "person#{n}@example.com" }
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end
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```
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The value just needs to support the `#next` method. Here the next value will be 'a', then 'b', etc.
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Traits
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------
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Traits allow you to group attributes together and then apply them
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to any factory.
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```ruby
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factory :user, aliases: [:author]
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factory :story do
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title "My awesome story"
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author
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trait :published do
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published true
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end
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trait :unpublished do
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published false
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end
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trait :week_long_publishing do
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start_at { 1.week.ago }
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end_at { Time.now }
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end
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trait :month_long_publishing do
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start_at { 1.month.ago }
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end_at { Time.now }
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end
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factory :week_long_published_story, traits: [:published, :week_long_publishing]
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factory :month_long_published_story, traits: [:published, :month_long_publishing]
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factory :week_long_unpublished_story, traits: [:unpublished, :week_long_publishing]
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factory :month_long_unpublished_story, traits: [:unpublished, :month_long_publishing]
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end
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```
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Traits can be used as attributes:
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```ruby
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factory :week_long_published_story_with_title, parent: :story do
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published
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week_long_publishing
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title { "Publishing that was started at #{start_at}" }
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end
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```
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Traits that define the same attributes won't raise AttributeDefinitionErrors;
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the trait that defines the attribute latest gets precedence.
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```ruby
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factory :user do
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name "Friendly User"
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login { name }
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trait :male do
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name "John Doe"
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gender "Male"
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login { "#{name} (M)" }
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end
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trait :female do
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name "Jane Doe"
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gender "Female"
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login { "#{name} (F)" }
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end
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trait :admin do
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admin true
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login { "admin-#{name}" }
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end
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factory :male_admin, traits: [:male, :admin] # login will be "admin-John Doe"
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factory :female_admin, traits: [:admin, :female] # login will be "Jane Doe (F)"
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end
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```
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You can also override individual attributes granted by a trait in subclasses.
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```ruby
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factory :user do
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name "Friendly User"
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login { name }
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trait :male do
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name "John Doe"
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gender "Male"
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login { "#{name} (M)" }
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end
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factory :brandon do
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male
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name "Brandon"
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end
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end
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```
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Traits can also be passed in as a list of symbols when you construct an instance from factory_girl.
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|
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```ruby
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factory :user do
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name "Friendly User"
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trait :male do
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name "John Doe"
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gender "Male"
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end
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trait :admin do
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admin true
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end
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end
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# creates an admin user with gender "Male" and name "Jon Snow"
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create(:user, :admin, :male, name: "Jon Snow")
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```
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This ability works with `build`, `build_stubbed`, `attributes_for`, and `create`.
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`create_list` and `build_list` methods are supported as well. Just remember to pass
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the number of instances to create/build as second parameter, as documented in the
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"Building or Creating Multiple Records" section of this file.
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|
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```ruby
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factory :user do
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name "Friendly User"
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trait :admin do
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admin true
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end
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end
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# creates 3 admin users with gender "Male" and name "Jon Snow"
|
|
create_list(:user, 3, :admin, :male, name: "Jon Snow")
|
|
```
|
|
|
|
Traits can be used with associations easily too:
|
|
|
|
```ruby
|
|
factory :user do
|
|
name "Friendly User"
|
|
|
|
trait :admin do
|
|
admin true
|
|
end
|
|
end
|
|
|
|
factory :post do
|
|
association :user, :admin, name: 'John Doe'
|
|
end
|
|
|
|
# creates an admin user with name "John Doe"
|
|
create(:post).user
|
|
```
|
|
|
|
When you're using association names that're different than the factory:
|
|
|
|
```ruby
|
|
factory :user do
|
|
name "Friendly User"
|
|
|
|
trait :admin do
|
|
admin true
|
|
end
|
|
end
|
|
|
|
factory :post do
|
|
association :author, :admin, factory: :user, name: 'John Doe'
|
|
# or
|
|
association :author, factory: [:user, :admin], name: 'John Doe'
|
|
end
|
|
|
|
# creates an admin user with name "John Doe"
|
|
create(:post).author
|
|
```
|
|
|
|
Finally, traits can be used within other traits to mix in their attributes.
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
factory :order do
|
|
trait :completed do
|
|
completed_at { 3.days.ago }
|
|
end
|
|
|
|
trait :refunded do
|
|
completed
|
|
refunded_at { 1.day.ago }
|
|
end
|
|
end
|
|
end
|
|
```
|
|
|
|
Callbacks
|
|
---------
|
|
|
|
factory\_girl makes available four callbacks for injecting some code:
|
|
|
|
* after(:build) - called after a factory is built (via `FactoryGirl.build`, `FactoryGirl.create`)
|
|
* before(:create) - called before a factory is saved (via `FactoryGirl.create`)
|
|
* after(:create) - called after a factory is saved (via `FactoryGirl.create`)
|
|
* after(:stub) - called after a factory is stubbed (via `FactoryGirl.build_stubbed`)
|
|
|
|
Examples:
|
|
|
|
```ruby
|
|
# Define a factory that calls the generate_hashed_password method after it is built
|
|
factory :user do
|
|
after(:build) { |user| generate_hashed_password(user) }
|
|
end
|
|
```
|
|
|
|
Note that you'll have an instance of the user in the block. This can be useful.
|
|
|
|
You can also define multiple types of callbacks on the same factory:
|
|
|
|
```ruby
|
|
factory :user do
|
|
after(:build) { |user| do_something_to(user) }
|
|
after(:create) { |user| do_something_else_to(user) }
|
|
end
|
|
```
|
|
|
|
Factories can also define any number of the same kind of callback. These callbacks will be executed in the order they are specified:
|
|
|
|
```ruby
|
|
factory :user do
|
|
after(:create) { this_runs_first }
|
|
after(:create) { then_this }
|
|
end
|
|
```
|
|
|
|
Calling `create` will invoke both `after_build` and `after_create` callbacks.
|
|
|
|
Also, like standard attributes, child factories will inherit (and can also define) callbacks from their parent factory.
|
|
|
|
Multiple callbacks can be assigned to run a block; this is useful when building various strategies that run the same code (since there are no callbacks that are shared across all strategies).
|
|
|
|
```ruby
|
|
factory :user do
|
|
callback(:after_stub, :before_create) { do_something }
|
|
after(:stub, :create) { do_something_else }
|
|
before(:create, :custom) { do_a_third_thing }
|
|
end
|
|
```
|
|
|
|
To override callbacks for all factories, define them within the
|
|
`FactoryGirl.define` block:
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
after(:build) { |object| puts "Built #{object}" }
|
|
after(:create) { |object| AuditLog.create(attrs: object.attributes) }
|
|
|
|
factory :user do
|
|
name "John Doe"
|
|
end
|
|
end
|
|
```
|
|
|
|
You can also call callbacks that rely on `Symbol#to_proc`:
|
|
|
|
```ruby
|
|
# app/models/user.rb
|
|
class User < ActiveRecord::Base
|
|
def confirm!
|
|
# confirm the user account
|
|
end
|
|
end
|
|
|
|
# spec/factories.rb
|
|
FactoryGirl.define do
|
|
factory :user do
|
|
after :create, &:confirm!
|
|
end
|
|
end
|
|
|
|
create(:user) # creates the user and confirms it
|
|
```
|
|
|
|
Modifying factories
|
|
-------------------
|
|
|
|
If you're given a set of factories (say, from a gem developer) but want to change them to fit into your application better, you can
|
|
modify that factory instead of creating a child factory and adding attributes there.
|
|
|
|
If a gem were to give you a User factory:
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
factory :user do
|
|
full_name "John Doe"
|
|
sequence(:username) { |n| "user#{n}" }
|
|
password "password"
|
|
end
|
|
end
|
|
```
|
|
|
|
Instead of creating a child factory that added additional attributes:
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
factory :application_user, parent: :user do
|
|
full_name "Jane Doe"
|
|
date_of_birth { 21.years.ago }
|
|
gender "Female"
|
|
health 90
|
|
end
|
|
end
|
|
```
|
|
|
|
You could modify that factory instead.
|
|
|
|
```ruby
|
|
FactoryGirl.modify do
|
|
factory :user do
|
|
full_name "Jane Doe"
|
|
date_of_birth { 21.years.ago }
|
|
gender "Female"
|
|
health 90
|
|
end
|
|
end
|
|
```
|
|
|
|
When modifying a factory, you can change any of the attributes you want (aside from callbacks).
|
|
|
|
`FactoryGirl.modify` must be called outside of a `FactoryGirl.define` block as it operates on factories differently.
|
|
|
|
A caveat: you can only modify factories (not sequences or traits) and callbacks *still compound as they normally would*. So, if
|
|
the factory you're modifying defines an `after(:create)` callback, you defining an `after(:create)` won't override it, it'll just get run after the first callback.
|
|
|
|
Building or Creating Multiple Records
|
|
-------------------------------------
|
|
|
|
Sometimes, you'll want to create or build multiple instances of a factory at once.
|
|
|
|
```ruby
|
|
built_users = build_list(:user, 25)
|
|
created_users = create_list(:user, 25)
|
|
```
|
|
|
|
These methods will build or create a specific amount of factories and return them as an array.
|
|
To set the attributes for each of the factories, you can pass in a hash as you normally would.
|
|
|
|
```ruby
|
|
twenty_year_olds = build_list(:user, 25, date_of_birth: 20.years.ago)
|
|
```
|
|
|
|
There's also a set of `*_pair` methods for creating two records at a time:
|
|
|
|
```ruby
|
|
built_users = build_pair(:user) # array of two built users
|
|
created_users = create_pair(:user) # array of two created users
|
|
```
|
|
|
|
Custom Construction
|
|
-------------------
|
|
|
|
If you want to use factory_girl to construct an object where some attributes
|
|
are passed to `initialize` or if you want to do something other than simply
|
|
calling `new` on your build class, you can override the default behavior by
|
|
defining `initialize_with` on your factory. Example:
|
|
|
|
```ruby
|
|
# user.rb
|
|
class User
|
|
attr_accessor :name, :email
|
|
|
|
def initialize(name)
|
|
@name = name
|
|
end
|
|
end
|
|
|
|
# factories.rb
|
|
sequence(:email) { |n| "person#{n}@example.com" }
|
|
|
|
factory :user do
|
|
ignore do
|
|
name "Jane Doe"
|
|
end
|
|
|
|
email
|
|
initialize_with { new(name) }
|
|
end
|
|
|
|
build(:user).name # Jane Doe
|
|
```
|
|
|
|
Notice that I ignored the `name` attribute. If you don't want attributes
|
|
reassigned after your object has been instantiated, you'll want to `ignore` them.
|
|
|
|
Although factory_girl is written to work with ActiveRecord out of the box, it
|
|
can also work with any Ruby class. For maximum compatibiltiy with ActiveRecord,
|
|
the default initializer builds all instances by calling new on your build class
|
|
without any arguments. It then calls attribute writer methods to assign all the
|
|
attribute values. While that works fine for ActiveRecord, it actually doesn't
|
|
work for almost any other Ruby class.
|
|
|
|
You can override the initializer in order to:
|
|
|
|
* Build non-ActiveRecord objects that require arguments to `initialize`
|
|
* Use a method other than `new` to instantiate the instance
|
|
* Do crazy things like decorate the instance after it's built
|
|
|
|
When using `initialize_with`, you don't have to declare the class itself when
|
|
calling `new`; however, any other class methods you want to call will have to
|
|
be called on the class explicitly.
|
|
|
|
For example:
|
|
|
|
```ruby
|
|
factory :user do
|
|
ignore do
|
|
name "John Doe"
|
|
end
|
|
|
|
initialize_with { User.build_with_name(name) }
|
|
end
|
|
```
|
|
|
|
You can also access all public attributes within the `initialize_with` block
|
|
by calling `attributes`:
|
|
|
|
```ruby
|
|
factory :user do
|
|
ignore do
|
|
comments_count 5
|
|
end
|
|
|
|
name "John Doe"
|
|
|
|
initialize_with { new(attributes) }
|
|
end
|
|
```
|
|
|
|
This will build a hash of all attributes to be passed to `new`. It won't
|
|
include ignored attributes, but everything else defined in the factory will be
|
|
passed (associations, evalued sequences, etc.)
|
|
|
|
You can define `initialize_with` for all factories by including it in the
|
|
`FactoryGirl.define` block:
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
initialize_with { new("Awesome first argument") }
|
|
end
|
|
```
|
|
|
|
When using `initialize_with`, attributes accessed from within the `initialize_with`
|
|
block are assigned *only* in the constructor; this equates to roughly the
|
|
following code:
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
factory :user do
|
|
initialize_with { new(name) }
|
|
|
|
name { 'value' }
|
|
end
|
|
end
|
|
|
|
build(:user)
|
|
# runs
|
|
User.new('value')
|
|
```
|
|
|
|
This prevents duplicate assignment; in versions of factory_girl before 4.0, it
|
|
would run this:
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
factory :user do
|
|
initialize_with { new(name) }
|
|
|
|
name { 'value' }
|
|
end
|
|
end
|
|
|
|
build(:user)
|
|
# runs
|
|
user = User.new('value')
|
|
user.name = 'value'
|
|
```
|
|
|
|
Custom Strategies
|
|
-----------------
|
|
|
|
There are times where you may want to extend behavior of factory\_girl by
|
|
adding a custom build strategy.
|
|
|
|
Strategies define two methods: `association` and `result`. `association`
|
|
receives a `FactoryGirl::FactoryRunner` instance, upon which you can call
|
|
`run`, overriding the strategy if you want. The second method, `result`,
|
|
receives a `FactoryGirl::Evaluation` instance. It provides a way to trigger
|
|
callbacks (with `notify`), `object` or `hash` (to get the result instance or a
|
|
hash based on the attributes defined in the factory), and `create`, which
|
|
executes the `to_create` callback defined on the factory.
|
|
|
|
To understand how factory\_girl uses strategies internally, it's probably
|
|
easiest to just view the source for each of the four default strategies.
|
|
|
|
Here's an example of composing a strategy using
|
|
`FactoryGirl::Strategy::Create` to build a JSON representation of your model.
|
|
|
|
```ruby
|
|
class JsonStrategy
|
|
def initialize
|
|
@strategy = FactoryGirl.strategy_by_name(:create).new
|
|
end
|
|
|
|
delegate :association, to: :@strategy
|
|
|
|
def result(evaluation)
|
|
@strategy.result(evaluation).to_json
|
|
end
|
|
end
|
|
```
|
|
|
|
For factory\_girl to recognize the new strategy, you can register it:
|
|
|
|
```ruby
|
|
FactoryGirl.register_strategy(:json, JsonStrategy)
|
|
```
|
|
|
|
This allows you to call
|
|
|
|
```ruby
|
|
FactoryGirl.json(:user)
|
|
```
|
|
|
|
Finally, you can override factory\_girl's own strategies if you'd like by
|
|
registering a new object in place of the strategies.
|
|
|
|
Custom Callbacks
|
|
----------------
|
|
|
|
Custom callbacks can be defined if you're using custom strategies:
|
|
|
|
```ruby
|
|
class JsonStrategy
|
|
def initialize
|
|
@strategy = FactoryGirl.strategy_by_name(:create).new
|
|
end
|
|
|
|
delegate :association, to: :@strategy
|
|
|
|
def result(evaluation)
|
|
result = @strategy.result(evaluation)
|
|
evaluation.notify(:before_json, result)
|
|
|
|
result.to_json.tap do |json|
|
|
evaluation.notify(:after_json, json)
|
|
evaluation.notify(:make_json_awesome, json)
|
|
end
|
|
end
|
|
end
|
|
|
|
FactoryGirl.register_strategy(:json, JsonStrategy)
|
|
|
|
FactoryGirl.define do
|
|
factory :user do
|
|
before(:json) { |user| do_something_to(user) }
|
|
after(:json) { |user_json| do_something_to(user_json) }
|
|
callback(:make_json_awesome) { |user_json| do_something_to(user_json) }
|
|
end
|
|
end
|
|
```
|
|
|
|
Custom Methods to Persist Objects
|
|
---------------------------------
|
|
|
|
By default, creating a record will call `save!` on the instance; since this
|
|
may not always be ideal, you can override that behavior by defining
|
|
`to_create` on the factory:
|
|
|
|
```ruby
|
|
factory :different_orm_model do
|
|
to_create { |instance| instance.persist! }
|
|
end
|
|
```
|
|
|
|
To disable the persistence method altogether on create, you can `skip_create`
|
|
for that factory:
|
|
|
|
```ruby
|
|
factory :user_without_database do
|
|
skip_create
|
|
end
|
|
```
|
|
|
|
To override `to_create` for all factories, define it within the
|
|
`FactoryGirl.define` block:
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
to_create { |instance| instance.persist! }
|
|
|
|
|
|
factory :user do
|
|
name "John Doe"
|
|
end
|
|
end
|
|
```
|
|
|
|
ActiveSupport Instrumentation
|
|
-----------------------------
|
|
|
|
In order to track what factories are created (and with what build strategy),
|
|
`ActiveSupport::Notifications` are included to provide a way to subscribe to
|
|
factories being run. One example would be to track factories based on a
|
|
threshold of execution time.
|
|
|
|
```ruby
|
|
ActiveSupport::Notifications.subscribe("factory_girl.run_factory") do |name, start, finish, id, payload|
|
|
execution_time_in_seconds = finish - start
|
|
|
|
if execution_time_in_seconds >= 0.5
|
|
$stderr.puts "Slow factory: #{payload[:name]} using strategy #{payload[:strategy]}"
|
|
end
|
|
end
|
|
```
|
|
|
|
Another example would be tracking all factories and how they're used
|
|
throughout your test suite. If you're using RSpec, it's as simple as adding a
|
|
`before(:suite)` and `after(:suite)`:
|
|
|
|
```ruby
|
|
config.before(:suite) do
|
|
@factory_girl_results = {}
|
|
ActiveSupport::Notifications.subscribe("factory_girl.run_factory") do |name, start, finish, id, payload|
|
|
factory_name = payload[:name]
|
|
strategy_name = payload[:strategy]
|
|
@factory_girl_results[factory_name] ||= {}
|
|
@factory_girl_results[factory_name][strategy_name] ||= 0
|
|
@factory_girl_results[factory_name][strategy_name] += 1
|
|
end
|
|
end
|
|
|
|
config.after(:suite) do
|
|
puts @factory_girl_results
|
|
end
|
|
```
|
|
|
|
Rails Preloaders and RSpec
|
|
--------------------------
|
|
|
|
When running RSpec with a Rails preloader such as `spring` or `zeus`, it's possible
|
|
to encounter an `ActiveRecord::AssociationTypeMismatch` error when creating a factory
|
|
with associations, as below:
|
|
|
|
```ruby
|
|
FactoryGirl.define do
|
|
factory :united_states, class: Location do
|
|
name 'United States'
|
|
association :location_group, factory: :north_america
|
|
end
|
|
|
|
factory :north_america, class: LocationGroup do
|
|
name 'North America'
|
|
end
|
|
end
|
|
```
|
|
|
|
The error occurs during the run of the test suite:
|
|
|
|
```
|
|
Failure/Error: united_states = create(:united_states)
|
|
ActiveRecord::AssociationTypeMismatch:
|
|
LocationGroup(#70251250797320) expected, got LocationGroup(#70251200725840)
|
|
```
|
|
|
|
The two possible solutions are to either run the suite without the preloader, or
|
|
to add `FactoryGirl.reload` to the RSpec configuration, like so:
|
|
|
|
```ruby
|
|
RSpec.configure do |config|
|
|
config.before(:suite) { FactoryGirl.reload }
|
|
end
|
|
```
|
|
|
|
Using Without Bundler
|
|
---------------------
|
|
|
|
If you're not using Bundler, be sure to have the gem installed and call:
|
|
|
|
```ruby
|
|
require 'factory_girl'
|
|
```
|
|
|
|
Once required, assuming you have a directory structure of `spec/factories` or
|
|
`test/factories`, all you'll need to do is run
|
|
|
|
```ruby
|
|
FactoryGirl.find_definitions
|
|
```
|
|
|
|
If you're using a separate directory structure for your factories, you can
|
|
change the definition file paths before trying to find definitions:
|
|
|
|
```ruby
|
|
FactoryGirl.definition_file_paths = %w(custom_factories_directory)
|
|
FactoryGirl.find_definitions
|
|
```
|
|
|
|
If you don't have a separate directory of factories and would like to define
|
|
them inline, that's possible as well:
|
|
|
|
```ruby
|
|
require 'factory_girl'
|
|
|
|
FactoryGirl.define do
|
|
factory :user do
|
|
name 'John Doe'
|
|
date_of_birth { 21.years.ago }
|
|
end
|
|
end
|
|
```
|