Rspec. Delete action doesn't work with let() - ruby-on-rails

Question

I have Rspec testing controller actions via visiting pages.
And when I'm declaring new object through let() for create and edit actions - it's all fine. But for delete it doesn't work and I have to declare instance variable to make it pass.
My goal is to get rid of instance variable declaration in delete action.
It stops me from finishing re-factoring and I want to know why this happen?
Maybe it's somehow related to Capybara scope.
Failed tests looks like:
Failure/Error: it {should have_content('delete')}
expected #has_content?("delete") to return true, got false
and
Failure/Error: expect{click_link('delete')}.to change(Crew, :count).by(-1)
Capybara::ElementNotFound:
Unable to find link "delete"
My whole test
require 'spec_helper'
describe 'CrewPage' do
subject {page}
let(:user) {FactoryGirl.create(:user)}
let(:crew) {Crew.create(name: name, secondname: secondname, rate: rate)}
let(:name) {'Name'}
let(:secondname) {'First'}
let(:rate) {1000}
before {sign_in(user)}
#==============================New page===========>>
describe 'new crew member page' do
before {visit new_crew_path}
it {should have_title('New member')}
let(:submit) {"Create"}
context 'invalid creation' do
it 'should not create crew member' do
expect{click_button submit}.not_to change(Crew, :count)
end
end
context 'valid crew member creation' do
before do
fill_in 'Name', with: name
fill_in 'Secondname', with: secondname
fill_in 'Rate', with: rate
end
it 'should create crew member' do
expect{click_button submit}.to change(Crew, :count).by(1)
end
end
end
#==============================Show page===========>>
describe 'show page' do
before {visit crew_path(crew)}
it {should have_title("#{crew.combine_names} profile")}
end
#==============================Edit page===========>>
describe 'edit page' do
let(:reload_n) {name*2}
let(:reload_sn) {secondname*2}
let(:reload_r) {rate*2}
before {visit edit_crew_path(crew)}
it {should have_title('Edit panel')}
context 'successfull edit' do
before do
fill_in 'Name', with: reload_n
fill_in 'Secondname', with: reload_sn
fill_in 'Rate', with: reload_r
click_button('Save')
end
it {should have_content(reload_n)}
it {should have_content(reload_sn)}
it {should have_content(reload_r)}
end
end
#==============================Delete action===========>>
describe 'delete action from index page' do
before do
#crew = Crew.create(name: name, secondname: secondname, rate: rate)
visit root_path
end
it {should have_content('delete')}
it 'should delete crew member' do
expect{click_link('delete')}.to change(Crew, :count).by(-1)
end
end
end

Answer 1

let block is not executed unless it is called in the test itself. Because you are not using this variable prior to visit_page, crew model is not created and hence it is not displayed on the page capybara is playing with. If you want it to execute before each test, you have to call let! instead:
let!(:crew) { Crew.create(name: name, secondname: secondname, rate: rate)}