Passing variable between multiple contexts with Rspec - ruby-on-rails

Question

I'm writing some tests using FactoryGirl and Rspec.
spec/factories/students.rb:
FactoryGirl.define do
factory :student do
end
factory :student_with_profile_and_identity, class: 'Student' do
after(:create) do |student|
create(:profile, profileable: student)
create(:student_identity, student: student)
end
end
end
spec/factories/profiles.rb:
FactoryGirl.define do
factory :profile do
birthday { Faker::Date.birthday(15, 150) }
sequence(:email) { |i| "profile_#{i}#email.com" }
first_name { Faker::Name.first_name }
last_name { Faker::Name.first_name }
password { Faker::Internet.password(6, 72, true, true) }
end
end
spec/factories/student_identities.rb:
FactoryGirl.define do
factory :student_identity do
provider { ['facebook.com', 'google.com', 'twitter.com'].sample }
uid { Faker::Number.number(10) }
end
end
spec/requests/authorizations_spec.rb:
require 'rails_helper'
RSpec.describe 'Authorizations', type: :request do
describe 'POST /v1/authorizations/sign_in' do
let!(:student) { create(:student_with_profile_and_identity) }
context 'when the request is valid' do
subject do
post '/v1/authorizations/sign_in',
params: credentials
end
context "user signs up via social network" do
let(:credentials) do
{
authorization: {
student: {
profile_attributes: {
email: student.profile.email
},
student_identities_attributes: {
provider: student.student_identities[0].provider,
uid: student.student_identities[0].uid
}
}
}
}
end
it 'returns an authentication token' do
subject
p "1 student.profile.inspect #{student.profile.inspect}"
expect(json['token']).to(be_present)
end
end
context 'when the user has already an account' do
let(:credentials) do
{
authorization: {
email: student.profile.email,
password: student.profile.password
}
}
end
it 'returns an authentication token' do
p "2 student.profile.inspect #{student.profile.inspect}"
subject
expect(json['token']).to(be_present)
end
end
end
end
end
Almost all tests are passing... the problem is that:
It's creating a new student in every context. I'd expect the let!(:student) { ... } to be something like "singleton", in other words, once it's created/defined here let!(:student) { create(:student_with_profile_and_identity) } it won't be called anymore.
Ex: the logs are like this:
"1 student.profile.inspect #<Profile id: 1, email: \"profile_1#email.com\", profileable_type: \"Student\", profileable_id: 1>"
"2 student.profile.inspect #<Profile id: 2, email: \"profile_2#email.com\", profileable_type: \"Student\", profileable_id: 2>"
While I'd expect the instances to be the same.
Am I missing something?

Answer 1

In RSpec, let and let! are the same thing, except that let is lazy and let! is eager:
Use let to define a memoized helper method. The value will be cached across multiple calls in the same example but not across examples.
Note that let is lazy-evaluated: it is not evaluated until the first time the method it defines is invoked. You can use let! to force the method's invocation before each example.
If you want something to persist through all examples, you can use a before hook...before(:context) sounds like it might be what you're wanting. You might be able to setup a helper method that memoizes in a before block, to avoid having to use an instance variable everywhere (per this comment):
def student
#student ||= create(:student_with_profile_and_identity)
end
before(:context) do
student # force student creation
end