Getting Started
Update Your Gemfile
If you're using Rails, you'll need to change the required version of factory_girl_rails
:
gem "factory_girl_rails", "~> 4.0"
If you're not using Rails, you'll just have to change the required version of factory_girl
:
gem "factory_girl", "~> 4.0"
JRuby users: factory_girl works with JRuby starting with 1.6.7.2 (latest stable, as per July 2012). JRuby has to be used in 1.9 mode, for that, use JRUBY_OPTS environment variable:
export JRUBY_OPTS=--1.9
Once your Gemfile is updated, you'll want to update your bundle.
Configure your test suite
RSpec
# spec/support/factory_girl.rb
RSpec.configure do |config|
config.include FactoryGirl::Syntax::Methods
end
# RSpec without Rails
RSpec.configure do |config|
config.include FactoryGirl::Syntax::Methods
config.before(:suite) do
FactoryGirl.find_definitions
end
end
Remember to require the above file in your rails_helper since the support folder isn't eagerly loaded
require 'support/factory_girl'
Test::Unit
class Test::Unit::TestCase
include FactoryGirl::Syntax::Methods
end
Cucumber
# env.rb (Rails example location - RAILS_ROOT/features/support/env.rb)
World(FactoryGirl::Syntax::Methods)
Spinach
class Spinach::FeatureSteps
include FactoryGirl::Syntax::Methods
end
Minitest
class Minitest::Unit::TestCase
include FactoryGirl::Syntax::Methods
end
Minitest::Spec
class Minitest::Spec
include FactoryGirl::Syntax::Methods
end
minitest-rails
class ActiveSupport::TestCase
include FactoryGirl::Syntax::Methods
end
If you do not include FactoryGirl::Syntax::Methods
in your test suite, then all factory_girl methods will need to be prefaced with FactoryGirl
.
Defining factories
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:
# This will guess the User class
FactoryGirl.define do
factory :user do
first_name "John"
last_name "Doe"
admin false
end
# This will use the User class (Admin would have been guessed)
factory :admin, class: User do
first_name "Admin"
last_name "User"
admin true
end
end
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.
Attempting to define multiple factories with the same name will raise an error.
Factories can be defined anywhere, but will be automatically loaded after
calling FactoryGirl.find_definitions
if factories are defined in files at the
following locations:
test/factories.rb
spec/factories.rb
test/factories/*.rb
spec/factories/*.rb
Using factories
factory_girl supports several different build strategies: build, create, attributes_for and build_stubbed:
# Returns a User instance that's not saved
user = build(:user)
# Returns a saved User instance
user = create(:user)
# Returns a hash of attributes that can be used to build a User instance
attrs = attributes_for(:user)
# Returns an object with all defined attributes stubbed out
stub = build_stubbed(:user)
# Passing a block to any of the methods above will yield the return object
create(:user) do |user|
user.posts.create(attributes_for(:post))
end
No matter which strategy is used, it's possible to override the defined attributes by passing a hash:
# Build a User instance and override the first_name property
user = build(:user, first_name: "Joe")
user.first_name
# => "Joe"
Dynamic Attributes
Most factory attributes can be added using static values that are evaluated when the factory is defined, but some attributes (such as associations and other attributes that must be dynamically generated) will need values assigned each time an instance is generated. These "dynamic" attributes can be added by passing a block instead of a parameter:
factory :user do
# ...
activation_code { User.generate_activation_code }
date_of_birth { 21.years.ago }
end
Because of the block syntax in Ruby, defining attributes as Hash
es (for
serialized/JSON columns, for example) requires two sets of curly brackets:
factory :program do
configuration { { auto_resolve: false, auto_define: true } }
end
Aliases
factory_girl allows you to define aliases to existing factories to make them easier to re-use. This could come in handy when, for example, your Post object has an author attribute that actually refers to an instance of a User class. While normally factory_girl can infer the factory name from the association name, in this case it will look for a author factory in vain. So, alias your user factory so it can be used under alias names.
factory :user, aliases: [:author, :commenter] do
first_name "John"
last_name "Doe"
date_of_birth { 18.years.ago }
end
factory :post do
# instead of
# association :author, factory: :user
title "How to read a book effectively"
body "There are five steps involved."
end
factory :comment do
commenter
# instead of
# association :commenter, factory: :user
body "Great article!"
end
Dependent Attributes
Attributes can be based on the values of other attributes using the evaluator that is yielded to dynamic attribute blocks:
factory :user do
first_name "Joe"
last_name "Blow"
email { "#{first_name}.#{last_name}@example.com".downcase }
end
create(:user, last_name: "Doe").email
# => "[email protected]"
Transient Attributes
There may be times where your code can be DRYed up by passing in transient attributes to factories.
factory :user do
transient do
rockstar true
upcased false
end
name { "John Doe#{" - Rockstar" if rockstar}" }
email { "#{name.downcase}@example.com" }
after(:create) do |user, evaluator|
user.name.upcase! if evaluator.upcased
end
end
create(:user, upcased: true).name
#=> "JOHN DOE - ROCKSTAR"
Static and dynamic attributes can be created as transient attributes. Transient attributes will be ignored within attributes_for and won't be set on the model, even if the attribute exists or you attempt to override it.
Within factory_girl's dynamic attributes, you can access transient attributes as you would expect. If you need to access the evaluator in a factory_girl callback, you'll need to declare a second block argument (for the evaluator) and access transient attributes from there.
Method Name / Reserved Word Attributes
If your attributes conflict with existing methods or reserved words you can define them with add_attribute
.
factory :dna do
add_attribute(:sequence) { 'GATTACA' }
end
factory :payment do
add_attribute(:method) { 'paypal' }
end
Inheritance
You can easily create multiple factories for the same class without repeating common attributes by nesting factories:
factory :post do
title "A title"
factory :approved_post do
approved true
end
end
approved_post = create(:approved_post)
approved_post.title # => "A title"
approved_post.approved # => true
You can also assign the parent explicitly:
factory :post do
title "A title"
end
factory :approved_post, parent: :post do
approved true
end
As mentioned above, it's good practice to define a basic factory for each class with only the attributes required to create it. Then, create more specific factories that inherit from this basic parent. Factory definitions are still code, so keep them DRY.
Associations
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.
factory :post do
# ...
end
You can also specify a different factory or override attributes:
factory :post do
# ...
association :author, factory: :user, last_name: "Writely"
end
The behavior of the association method varies depending on the build strategy used for the parent object.
# Builds and saves a User and a Post
post = create(:post)
post.new_record? # => false
post..new_record? # => false
# Builds and saves a User, and then builds but does not save a Post
post = build(:post)
post.new_record? # => true
post..new_record? # => false
To not save the associated object, specify strategy: :build in the factory:
factory :post do
# ...
association :author, factory: :user, strategy: :build
end
# Builds a User, and then builds a Post, but does not save either
post = build(:post)
post.new_record? # => true
post..new_record? # => true
Please note that the strategy: :build
option must be passed to an explicit call to association
,
and cannot be used with implicit associations:
factory :post do
# ...
author strategy: :build # <<< this does *not* work; causes author_id to be nil
Generating data for a has_many
relationship is a bit more involved,
depending on the amount of flexibility desired, but here's a surefire example
of generating associated data.
FactoryGirl.define do
# post factory with a `belongs_to` association for the user
factory :post do
title "Through the Looking Glass"
user
end
# user factory without associated posts
factory :user do
name "John Doe"
# user_with_posts will create post data after the user has been created
factory :user_with_posts do
# posts_count is declared as a transient attribute and available in
# attributes on the factory, as well as the callback via the evaluator
transient do
posts_count 5
end
# the after(:create) yields two values; the user instance itself and the
# evaluator, which stores all values from the factory, including transient
# attributes; `create_list`'s second argument is the number of records
# to create and we make sure the user is associated properly to the post
after(:create) do |user, evaluator|
create_list(:post, evaluator.posts_count, user: user)
end
end
end
end
This allows us to do:
create(:user).posts.length # 0
create(:user_with_posts).posts.length # 5
create(:user_with_posts, posts_count: 15).posts.length # 15
Generating data for a has_and_belongs_to_many
relationship is very similar
to the above has_many
relationship, with a small change, you need to pass an
array of objects to the model's pluralized attribute name rather than a single
object to the singular version of the attribute name.
Here's an example with two models that are related via
has_and_belongs_to_many
:
FactoryGirl.define do
# language factory with a `belongs_to` association for the profile
factory :language do
title "Through the Looking Glass"
profile
end
# profile factory without associated languages
factory :profile do
name "John Doe"
# profile_with_languages will create language data after the profile has
# been created
factory :profile_with_languages do
# languages_count is declared as an ignored attribute and available in
# attributes on the factory, as well as the callback via the evaluator
transient do
languages_count 5
end
# the after(:create) yields two values; the profile instance itself and
# the evaluator, which stores all values from the factory, including
# ignored attributes; `create_list`'s second argument is the number of
# records to create and we make sure the profile is associated properly
# to the language
after(:create) do |profile, evaluator|
create_list(:language, evaluator.languages_count, profiles: [profile])
end
end
end
end
This allows us to do:
create(:profile).languages.length # 0
create(:profile_with_languages).languages.length # 5
create(:profile_with_languages, languages_count: 15).languages.length # 15
Sequences
Unique values in a specific format (for example, e-mail addresses) can be
generated using sequences. Sequences are defined by calling sequence
in a
definition block, and values in a sequence are generated by calling
generate
:
# Defines a new sequence
FactoryGirl.define do
sequence :email do |n|
"person#{n}@example.com"
end
end
generate :email
# => "[email protected]"
generate :email
# => "[email protected]"
Sequences can be used in dynamic attributes:
factory :invite do
invitee { generate(:email) }
end
Or as implicit attributes:
factory :user do
email # Same as `email { generate(:email) }`
end
And it's also possible to define an in-line sequence that is only used in a particular factory:
factory :user do
sequence(:email) { |n| "person#{n}@example.com" }
end
You can also override the initial value:
factory :user do
sequence(:email, 1000) { |n| "person#{n}@example.com" }
end
Without a block, the value will increment itself, starting at its initial value:
factory :post do
sequence(:position)
end
Sequences can also have aliases. The sequence aliases share the same counter:
factory :user do
sequence(:email, 1000, aliases: [:sender, :receiver]) { |n| "person#{n}@example.com" }
end
# will increase value counter for :email which is shared by :sender and :receiver
generate(:sender)
Define aliases and use default value (1) for the counter
factory :user do
sequence(:email, aliases: [:sender, :receiver]) { |n| "person#{n}@example.com" }
end
Setting the value:
factory :user do
sequence(:email, 'a', aliases: [:sender, :receiver]) { |n| "person#{n}@example.com" }
end
The value just needs to support the #next
method. Here the next value will be 'a', then 'b', etc.
Traits
Traits allow you to group attributes together and then apply them to any factory.
factory :user, aliases: [:author]
factory :story do
title "My awesome story"
trait :published do
published true
end
trait :unpublished do
published false
end
trait :week_long_publishing do
start_at { 1.week.ago }
end_at { Time.now }
end
trait :month_long_publishing do
start_at { 1.month.ago }
end_at { Time.now }
end
factory :week_long_published_story, traits: [:published, :week_long_publishing]
factory :month_long_published_story, traits: [:published, :month_long_publishing]
factory :week_long_unpublished_story, traits: [:unpublished, :week_long_publishing]
factory :month_long_unpublished_story, traits: [:unpublished, :month_long_publishing]
end
Traits can be used as attributes:
factory :week_long_published_story_with_title, parent: :story do
published
week_long_publishing
title { "Publishing that was started at #{start_at}" }
end
Traits that define the same attributes won't raise AttributeDefinitionErrors; the trait that defines the attribute latest gets precedence.
factory :user do
name "Friendly User"
login { name }
trait :male do
name "John Doe"
gender "Male"
login { "#{name} (M)" }
end
trait :female do
name "Jane Doe"
gender "Female"
login { "#{name} (F)" }
end
trait :admin do
admin true
login { "admin-#{name}" }
end
factory :male_admin, traits: [:male, :admin] # login will be "admin-John Doe"
factory :female_admin, traits: [:admin, :female] # login will be "Jane Doe (F)"
end
You can also override individual attributes granted by a trait in subclasses.
factory :user do
name "Friendly User"
login { name }
trait :male do
name "John Doe"
gender "Male"
login { "#{name} (M)" }
end
factory :brandon do
male
name "Brandon"
end
end
Traits can also be passed in as a list of symbols when you construct an instance from factory_girl.
factory :user do
name "Friendly User"
trait :male do
name "John Doe"
gender "Male"
end
trait :admin do
admin true
end
end
# creates an admin user with gender "Male" and name "Jon Snow"
create(:user, :admin, :male, name: "Jon Snow")
This ability works with build
, build_stubbed
, attributes_for
, and create
.
create_list
and build_list
methods are supported as well. Just remember to pass
the number of instances to create/build as second parameter, as documented in the
"Building or Creating Multiple Records" section of this file.
factory :user do
name "Friendly User"
trait :admin do
admin true
end
end
# 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:
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:
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).
Traits can be used within other traits to mix in their attributes.
factory :order do
trait :completed do
completed_at { 3.days.ago }
end
trait :refunded do
completed
refunded_at { 1.day.ago }
end
end
Finally, traits can accept transient attributes.
factory :invoice do
trait :with_amount do
transient do
amount 1
end
after(:create) do |invoice, evaluator|
create :line_item, invoice: invoice, amount: evaluator.amount
end
end
end
create :invoice, :with_amount, amount: 2
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:
# 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:
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:
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).
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:
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
:
# 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:
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:
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.
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.
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.
twenty_year_olds = build_list(:user, 25, date_of_birth: 20.years.ago)
build_stubbed_list
will give you fully stubbed out instances:
stubbed_users = build_stubbed_list(:user, 25) # array of stubbed users
There's also a set of *_pair
methods for creating two records at a time:
built_users = build_pair(:user) # array of two built users
created_users = create_pair(:user) # array of two created users
If you need multiple attribute hashes, attributes_for_list
will generate them:
users_attrs = attributes_for_list(:user, 25) # array of attribute hashes
Linting Factories
factory_girl allows for linting known factories:
FactoryGirl.lint
FactoryGirl.lint
creates each factory and catches any exceptions raised
during the creation process. FactoryGirl::InvalidFactoryError
is raised with
a list of factories (and corresponding exceptions) for factories which could
not be created.
Recommended usage of FactoryGirl.lint
is to run this in a task
before your test suite is executed.
Running it in a before(:suite)
,
will negatively impact the performance
of your tests
when running single tests.
Example Rake task:
# lib/tasks/factory_girl.rake
namespace :factory_girl do
desc "Verify that all FactoryGirl factories are valid"
task lint: :environment do
if Rails.env.test?
DatabaseCleaner.cleaning do
FactoryGirl.lint
end
else
system("bundle exec rake factory_girl:lint RAILS_ENV='test'")
exit $?.exitstatus
end
end
end
After calling FactoryGirl.lint
, you'll likely want to clear out the
database, as records will most likely be created. The provided example above
uses the database_cleaner gem to clear out the database; be sure to add the
gem to your Gemfile under the appropriate groups.
You can lint factories selectively by passing only factories you want linted:
factories_to_lint = FactoryGirl.factories.reject do |factory|
factory.name =~ /^old_/
end
FactoryGirl.lint factories_to_lint
This would lint all factories that aren't prefixed with old_
.
Traits can also be linted. This option verifies that each
and every trait of a factory generates a valid object on its own.
This is turned on by passing traits: true
to the lint
method:
FactoryGirl.lint traits: true
This can also be combined with other arguments:
FactoryGirl.lint factories_to_lint, traits: true
You can also specify the strategy used for linting:
FactoryGirl.lint strategy: :build
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:
# 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
name "Jane Doe"
email
initialize_with { new(name) }
end
build(:user).name # Jane Doe
Although factory_girl is written to work with ActiveRecord out of the box, it
can also work with any Ruby class. For maximum compatibility 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:
factory :user do
name "John Doe"
initialize_with { User.build_with_name(name) }
end
You can also access all public attributes within the initialize_with
block
by calling attributes
:
factory :user do
transient 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 transient 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:
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:
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:
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.
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:
FactoryGirl.register_strategy(:json, JsonStrategy)
This allows you to call
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:
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:
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:
factory :user_without_database do
skip_create
end
To override to_create
for all factories, define it within the
FactoryGirl.define
block:
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.
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)
:
factory_girl_results = {}
config.before(:suite) do
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:
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:
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:
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
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:
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:
require 'factory_girl'
FactoryGirl.define do
factory :user do
name 'John Doe'
date_of_birth { 21.years.ago }
end
end