Is it possible to pass arguments to let block during the call? - ruby-on-rails

Question

I've started to use Rspec and right now I wrote several successfully worked and pretty difficult tests. But as I need more practice I did refactor of these tests few times.
I not found an answer for my question in Rspec's documentation and that's why I here.
The question is about directive let that provides an ability to return some objects by first call and not only, you know.
My current part of rspec code is:
RSpec.describe 'Users', type: :request do
describe 'profiles' do
context 'should be visible by' do
it 'related company managers' do
company = create(:company)
sign_in create(:manager, :company, company: company) # Pay attention on this
get user_path(create(:member, :company, company: company)) # this
expect(response).to have_http_status 200
end
it 'related company owners' do
company = create(:company)
sign_in create(:owner, :company, company: company) # this
get user_path(create(:member, :company, company: company)) # and this
expect(response).to have_http_status 200
end
end
end
end
There are only two example of 63 that are under the User's spec, but they are enough. I want to refactor the code to use let which will define a method with parameters, like that:
RSpec.describe 'Users', type: :request do
let(:member) do |entity_name = :company, entity = create(entity_name)|
create :member, entity_name, entity_name => entity
end
let(:manager) do |entity_name = :company, entity = create(entity_name)|
create :manager, entity_name, entity_name => entity
end
let(:owner) do |entity_name = :company, entity = create(entity_name)|
create :owner, entity_name, entity_name => entity
end
describe 'profiles' do
context 'should be visible by' do
it 'related company managers' do
company = create(:company)
sign_in manager(:company, company) # Become more readable here
get user_path(member(:company, company)) # here
expect(response).to have_http_status 200
end
it 'related company owners' do
company = create(:company)
sign_in owner(:company, company) # here
get user_path(member(:company, company)) # and here.
expect(response).to have_http_status 200
end
end
end
end
Right after the refactor the Guard says:
1) Users profiles should be visible by related company managers
Failure/Error: sign_in manager(:company, company) # Become more readable here
ArgumentError:
wrong number of arguments (given 2, expected 0)
# ./spec/requests/users_spec.rb:38:in `block (4 levels) in <top (required)>'
From the memorized_helpers.rb of Rspec core I saw:
def let(name, &block)
# We have to pass the block directly to `define_method` to
# allow it to use method constructs like `super` and `return`.
raise "#let or #subject called without a block" if block.nil?
raise(
"#let or #subject called with a reserved name #initialize"
) if :initialize == name
MemoizedHelpers.module_for(self).__send__(:define_method, name, &block)
# Apply the memoization. The method has been defined in an ancestor
# module so we can use `super` here to get the value.
if block.arity == 1
define_method(name) { __memoized.fetch_or_store(name) { super(RSpec.current_example, &nil) } }
else
define_method(name) { __memoized.fetch_or_store(name) { super(&nil) } }
end
end
It looks like let's blocks should be defined with parameters. Or not?
I haven't enough experience to determine it and I would be glad to find it out.

Answer 1

I've found possible solution: return a lambda and call it in place
RSpec.describe 'Users', type: :request do
let(:member) do
->(entity_name = :company, entity = create(entity_name)) do
create :member, entity_name, entity_name => entity
end
end
let(:manager) do
->(entity_name = :company, entity = create(entity_name)) do
create :manager, entity_name, entity_name => entity
end
end
let(:owner) do
->(entity_name = :company, entity = create(entity_name)) do
create :owner, entity_name, entity_name => entity
end
end
describe 'profiles' do
context 'should be visible by' do
it 'related company managers' do
company = create(:company)
sign_in manager.(:company, company) # Pay attention on the dot here
get user_path(member.(:company, company)) # here
expect(response).to have_http_status 200
end
it 'related company owners' do
company = create(:company)
sign_in owner.(:company, company) # here
get user_path(member.(:company, company)) # and here.
expect(response).to have_http_status 200
end
end
end
end
This is not exactly that I want, but seems like.

Answer 2

I think you want something like:
RSpec.describe 'Users', type: :request do
describe 'profiles' do
let(:request) { get user_path(user) }
let(:user) { create(:member, :company, company: company) }
let(:company) { create(:company) }
shared_examples_for 'has visibility to user' do
before { sign_in employee }
it do
request
expect(response).to have_http_status(:success)
end
end
context 'manager' do
let(:employee) { create(:manager, company: company) }
it_behaves_like 'has visibility to user'
end
context 'owner' do
let(:employee) { create(:owner, company: company) }
it_behaves_like 'has visibility to user'
end
end
end
Similarly, you should be able to do something like:
it_behaves_like 'has visibility to user' do
let(:employee) { create(:manager, company: company) }
end
with shared examples. I suggest checking out http://www.betterspecs.org/.
(Aside, it's confusing to have a factory named :member and not :user since the GET request is for user_path; I recommend renaming it.)

Answer 3

The another solution is creation of helpers. For example, create a file in spec/support/users_helper.rb.
module UsersSpecHelper
def member(entity = :company)
create :member, *entity(entity)
end
def manager(entity = :company)
create :manager, *entity(entity)
end
def owner(entity = :company)
create :owner, *entity(entity)
end
private
def entity(entity)
if entity.is_a? Symbol
[entity, entity => create(entity)]
else
name = entity.class.to_s.downcase.to_sym
[name, name => entity]
end
end
end
RSpec.configure do |config|
config.include UsersSpecHelper, type: :request
end
Uncomment in spec/rails_helper.rb the line:
Dir[Rails.root.join('spec/support/**/*.rb')].each { |f| require f }
and then it can be used even better:
RSpec.describe 'Users', type: :request do
describe 'profiles' do
context 'should be visible by' do
it 'managers of related company' do
company = create(:company)
sign_in manager(company) # Changes are here
get user_path(member(company)) # here
expect(response).to have_http_status 200
end
it 'owners of related company' do
company = create(:company)
sign_in owner(company) # here
get user_path(member(company)) # and here.
expect(response).to have_http_status 200
end
end
end
end