Factory Girl: using sequence inline vs not inline - ruby-on-rails

Question

There are (at least?) two ways to use a sequence in factory girl:
Factory.sequence :my_id do |n|
"#{n}"
end
Factory.define :my_object do |mo|
mo.id Factory.next :my_id
end
and simply doing it inline:
Factory.define :my_object do |mo|
mo.sequence(:id) { |n| "#{n}" }
end
My question is this. If I use the inline version in two different factories, will there be two different sequences that both start at 1 and increment in tandem...meaning that if I create one of each type of factory object they will both have id 1?
If I use the externally defined sequence in two different factories am I guaranteed to get unique ids across the two objects? Meaning will the ids of each object be different?
I am trying to confirm if the behavior above is accurate because I'm working with a completely goofy data model trying to get rspec & factory girl to play nice with it. The designer of the database set things up so that different objects have to have ids generated that are unique across a set of unrelated objects. Changing the data model at this point is not a feasible solution though I'd really love to drag this stuff back onto the Rails.

Answer 1

When using externally defined sequences in two different factories you will see incrementing ids across the factories. However, when using inline sequences each factory will have their own sequence.
I created the example rake task below to illustrate this. It displays the following results:
*** External FactoryGirl Sequence Test Results ***
User Name: Name 1
User Name: Name 2
User Name: Name 3
User Name: Name 4
Role: Name 5
Role: Name 6
Role: Name 7
Role: Name 8
*** Internal FactoryGirl Sequence Test Results ***
User Name: Name 1
User Name: Name 2
User Name: Name 3
User Name: Name 4
Role: Role 1
Role: Role 2
Role: Role 3
Role: Role 4
As you can see, when using external sequences the number continues to increase as you move from the user to the role. However when using an inline sequence the increments are independent of each other.
The following schema files were used for this example:
create_table "users", :force => true do |t|
t.string "name"
t.string "email"
end
create_table "roles", :force => true do |t|
t.string "name"
end
The example rake task is:
require 'factory_girl_rails'
namespace :sequencetests do
Rake::Task[:environment].invoke
task :external do
FactoryGirl.factories.clear
desc "Factory Girl Sequence Test using an externally defined sequence"
puts "*** External FactoryGirl Sequence Test Results ***"
FactoryGirl.define do
sequence :name do |n|
"Name #{n}"
end
factory :user do |u|
name
end
factory :role do |r|
name
end
end
users = buildit(:user)
roles = buildit(:role)
puts( showit(users, "User Name: "))
puts( showit(roles, "Role: "))
end
task :inline do
FactoryGirl.factories.clear
puts "*** Internal FactoryGirl Sequence Test Results ***"
desc "Factory Girl Sequence Test using an inline sequence"
FactoryGirl.define do
factory :user do |u|
u.sequence(:name) {|n| "Name #{n}" }
end
factory :role do |r|
r.sequence(:name) {|n| "Role #{n}" }
end
end
users = buildit(:user)
roles = buildit(:role)
puts( showit(users, "User Name: "))
puts( showit(roles, "Role: "))
end
end
task sequencetests: ['sequencetests:external', 'sequencetests:inline']
def buildit(what)
items = []
4.times do
items << FactoryGirl.build(what)
end
items
end
def showit(items, prefix = "Name: ")
results = ""
items.each do |item|
results += "#{prefix}#{item.name}\n"
end
results
end
I hope this helps explain the different possibilities when using sequences in FactoryGirl.

Answer 2

Yes, the inline versions will create 2 independent sequences, each starting at 1