RSpec - losing post? - ruby-on-rails-4

Question

looks like I am losing 'San Francisco' at the start of the Update test in this example - not sure why - when I do a puts response.body at the end the Post Test everything looks ok - here is my flights_spec.rb:
require 'rails_helper'
require 'spec_helper'
require 'flight'
RSpec.describe FlightsController, type: :controller do
render_views
let(:flight0) { Flight.create(:destination => "Las Vegas") }
it "Get Test" do
puts 'Get Test'
get :index, :format => :json
puts "Body = " + response.body
expect(response.body).to include('Las Vegas')
end
it "Post Test" do
puts 'Post Test'
post :create, :flight => {:destination => "San Francisco"}
puts "Post status:" + response.status.to_s
expect(response).to redirect_to(assigns(:flight))
redirect_to(response.headers['Location'])
get :index, :format => :json
puts "Body = " + response.body
expect(response.body).to include("San Francisco")
end
it "Update Test" do
puts 'Delete Test'
get :index, :format => :json
puts "Body = " + response.body
expect(response.body).to include("San Francisco")
end
end

Answer 1

RSpec assumes that you are writing each test to be independent of the other tests. However, the way you have it here, Update Test relies on Post Test to create the data it needs. RSpec automatically undoes any changes you made between each test. You can think of each it block as resetting everything back to the initial state.
A quick fix would be to simply aim the delete at the Las Vegas object instead since this flight is already being recreated for each test because of the let statement:
it "Update Test" do
puts 'Delete Test'
get :index, :format => :json
puts "Body = " + response.body
expect(response.body).to include("Las Vegas")
# rest of your test
end
Also I just would note that you may run into issues with the let statement because it is lazily instantiated, meaning it may not actually create a Las Vegas flight until you actually try to use the flight0 variable in your test. You can fix that by simply adding a bang to the end, like this let!(:flight_0) {}.