Optimize Rails RSpec Tests - ruby-on-rails

I'm working on a test for my Rails 4 app and I'm pretty new to using RSpec. I have a controller named AppsController which has the standard index, new, show, create... methods and they all work the way Rails suggest Etc. "new" creates a new instance of the object and create actually saves it, show, shows it and index shows all of the object. Here are my current tests can anyone see any potential problems or things that i could improve?
FactoryGirl.define do
factory :developer do
email 'example#me.com'
password 'new_york'
password_confirmation 'new_york'
tos '1'
end
factory :app do
name 'New App'
tos '1'
end
factory :invalid_app, parent: :app do
name 'nil'
tos '0'
end
end
require 'spec_helper'
def create_valid!
post :create, app: app_attributes
end
def create_invalid!
post :create, app: app_invalid_attributes
end
def show!
get :show, id: app
end
def update_valid!
put :update, id: app, app: app_attributes
end
def update_invalid!
put :update, id: app, app: app_invalid_attributes
end
def delete!
delete :destroy, id: app
end
def http_success
expect(response).to be_success
end
def expect_template(view)
expect(response).to render_template(view)
end
describe AppsController do
render_views
before(:each) do
#developer = FactoryGirl.create(:developer)
#developer.confirm!
sign_in #developer
end
let(:app) { FactoryGirl.create(:app, developer: #developer) }
let(:app_attributes) { FactoryGirl.attributes_for(:app) }
let(:app_invalid_attributes) { FactoryGirl.attributes_for(:invalid_app) }
describe 'GET #index' do
it 'responds with an HTTP 200 status' do
get :index
http_success
end
it 'renders the :index view' do
get :index
expect_template(:index)
end
it 'populates #apps with the current_developers apps' do
app = FactoryGirl.create(:app, :developer => #developer)
get :index
expect(assigns(:app)).to eq([app])
end
end
describe 'POST #create' do
context 'with valid parameters' do
it 'creates a new app' do
expect { create_valid!
}.to change(App, :count).by(1)
end
it 'redirects to the new app keys' do
create_valid!
expect(response).to redirect_to keys_app_path(App.last)
end
end
context 'with invalid parameters' do
it 'does not create the new app' do
expect { create_invalid!
}.to_not change(App, :count)
end
it 'renders the :new view' do
create_invalid!
expect_template(:new)
end
end
end
describe 'GET #show' do
it 'responds with an HTTP 200 status' do
show!
http_success
end
it 'renders the :show view' do
show!
expect_template(:show)
end
it 'populates #app with the requested app' do
show!
expect(assigns(:app)).to eq(app)
end
end
describe 'PUT #update' do
context 'with valid parameters' do
it 'locates the requested app' do
update_valid!
expect(assigns(:app)).to eq(app)
end
it 'changes app attributes' do
update_valid!
expect(app.name).to eq('Updated App')
end
it 'redirects to the updated app' do
update_valid!
expect(response).to redirect_to app
end
end
context 'with invalid parameters' do
it 'locates the requested app' do
update_invalid!
expect(assigns(:app)).to eq(app)
end
it 'does not change app attributes' do
update_invalid!
expect(app.name).to_not eq('Updated App')
end
it 'renders the :edit view' do
update_invalid!
expect_template(:edit)
end
end
end
describe 'DELETE #destroy' do
it 'deletes the app' do
expect { delete!
}.to change(App, :count).by(-1)
end
it 'redirects to apps#index' do
delete!
expect(response).to redirect_to apps_url
end
end
end
count should have been changed by -1, but was changed by 0 - on DELETE #destroy
expecting <"new"> but rendering with <[]> - on POST #create
expected: "Updated App"
got: "New App" - on PUT #update
expecting <"edit"> but rendering with <[]> - on PUT #update
expected: [#<App id: nil, unique_id: "rOIc5p", developer_id: 18, name: "New App">]
got: nil - on GET #index

Small thing - your #http_success method is testing the exact same thing twice.
You could also factor out the references to app by putting a #let statement right after your #before block:
let(:app) { FactoryGirl.create(:app, developer: #developer) }
then in your specs, just
it 'renders the :show view' do
get :show, id: app
expect_template(:show)
end
Edit:
Then the order of operations will be 1) the #developer is created in the #before block, 2) the spec is entered, 3) at the first reference to app in the spec, the #let block will create an instance of an app.
That means you can't factor out the app creation in the #index spec, because in that case the spec will call the action before it creates the app.

A few things I thought of, reading your code:
You don't need to include parens on method calls taking no arguments. Just http_success will work.
You should get try to use the modern RSpec expectation syntax consistently. Instead of assigns(:app).should eq(app), use expect(assigns(:app)).to eq(app). (There's one exception to this, which is expectations on mocks (ie. should_receive(:message)), which will only take on the modern expect-to syntax as of RSpec 3.
For controller specs, I like to create little methods for each action that actually invokes the action. You'll notice you call get :show, id: app several times in the GET #show specs. To DRY up your specs a little more, you could instead write the following method within the describe block:
def show!
get :show, id: app
end
Try to use one Hash syntax consistently. What's more, Rails 4 can't be run with Ruby 1.8, so there's (nearly) no reason to use the hash-rocket Hash syntax.
If I'm getting really, really picky, I usually consider instance variables in a spec to be a smell. In almost all cases, instance variables should be refactored to a memoized let/given blocks.
If I'm getting really, really, really picky, I prefer to think of controller specs such as yours as strictly a unit test of the controller, not an integration test (that's what Capybara is for), and as such you shouldn't be exercising your model layer at all. You should only be testing that your controller is sending the right messages to the model layer. In other words, all the model layer stuff should be stubbed out. For example:
describe 'GET #show' do
let(:app) { stub(:app) }
before do
App.stub(:find).and_return(app)
end
it 'populates #app' do
get :show, id: app
assigns(:app).should eq(app)
end
end
I know this last is a personal preference, not a metaphysical truth or even necessarily a wide-spread standard convention, so you may choose to take it or leave it. I prefer it, because it keeps my specs very speedy, and gives me a very clear heuristic for when my controller actions are doing too much, and I might need to consider refactoring. It could be a good habit to get into.

First, I'm not certain but I suspect your invalid app factory may be wrong. Did you mean
factory :invalid_app, parent: :app do
name nil
tos '0'
end
nil as a ruby NilClass not "nil" as a string?
As for other comments about cleanup and stuff, here are a few of my thoughts.
You can avoid the need for some of your helper methods and duplication by using before blocks for each describe. Taking just your index tests you could have something more like
describe 'GET #index' do
before do
get :index
end
it 'responds with an HTTP 200 status' do
http_success
end
it 'renders the :index view' do
expect_template(:index)
end
it 'populates #apps with the current_developers apps' do
expect(assigns(:app)).to eq([app])
end
end
Notice also that you don't need to recreate app because your let is doing it as necessary.
On the failures, I suspect the delete count change could be failing because inside the expectation, the test framework is creating a new app (from the let) and then deleting it leading to a count change of 0. For that test, you need to make sure you're app is created outside of your expectation. Because you are using let, you could do that like this:
describe 'DELETE #destroy' do
it 'deletes the app' do
# ensure that app is already created
app
expect {
delete!
}.to change(App, :count).by(-1)
end
end
alternatively, change the let to a let! which will force the creation before the specs actually run.
As for other failures, thought #DanielWright suggested the helper methods, I find those complicate the debug. I can't see where you set the app name to "Updated App", for example. Perhaps a clearer test (for that particular one) would not use the helper methods but could be more explicit. Something like
describe 'PUT #update' do
let(:app_attributes) { FactoryGirl.attributes_for(:app, name: 'The New App Name') }
before do
put :update, id: app, app: app_attributes
end
context 'with valid parameters' do
it 'locates the requested app' do
expect(assigns(:app)).to eq(app)
end
it 'changes app attributes' do
# notice the reload which will make sure you refetch this from the db
expect(app.reload.name).to eq('The New App Name')
end
it 'redirects to the updated app' do
expect(response).to redirect_to app
end
end
end
For the other errors, you might want to start debugging your code. Are you certain it should work? Have you looked at output logs? Maybe the tests are doing there job and finding errors in your controller code. Have you done any step-through debugging?

Related

Testing with Rspec3 controllers with belongs_to association using instance_double

I'm new in testing and learning Rspec, and I can't git it working.
(I have read the book Effective testing with Rspec3, and many tutorials ...also pluralsight.com)
The situation is very simple. In a Companies controller I want to test de Create method, the company model belongs_to user, and is this the code:
I think the problem is when execute
in test: expect(Company).to receive(:new).with(company_params)
or in controller: #company.user=helpers.user
Controller:
class CompaniesController < SessionsController
def create
#company=Company.new(company_params)
#company.user=helpers.user
if #company.save()
redirect_to companies_path
else
render :edit
end
end
and Rspec:
RSpec.describe CompaniesController, type: :controller do
let(:user) { instance_double(User) }
before do
allow_any_instance_of(ApplicationHelper).to receive(:user){user}
allow(controller).to receive(:authorize){true}
end
describe 'Authenticated user with companies' do
let(:company_params) { {company:{name:"Albert",domain:"www.albert.com"}} }
let(:company) { instance_double(Company) }
before do
allow(Company).to receive(:new){company}
end
describe 'POST #create' do
context "with valid data" do
before { allow(company).to receive(:save){true} }
it "redirects to companies_path" do
expect(Company).to receive(:new).with(company_params)
expect(company).to receive(:user=).with(user)
post :create, params:{company: company_params}
expect(response).to redirect_to(companies_path)
end
My intention is very simple: Use instance_double to mock (or stub) #company, and Company.new, using instance double...to test the create action, and simulate the "save()" returning true...etc
I do not know if I explain myself very well, but given the create action of controlloer , how to test using mocks ans stubs, instance_double?
Thanks
First of all let me explain what we need to test here
def create
#company=Company.new(company_params)
#company.user=helpers.user
if #company.save()
redirect_to companies_path
else
render :edit
end
end
We are testing create action of a controller. First let us see what this action does? It's just takes comapany_params as input and create a company record in database.
Testing also goes like the same, we need to just pass the input that action required, and need to check whether it's creating record in database or not.
RSpec.describe CompaniesController, type: :controller do
let(:user) { instance_double(User) }
before do
# all your authentication stubing goes here
allow_any_instance_of(ApplicationHelper).to receive(:user){user}
allow(controller).to receive(:authorize){true}
end
describe 'POST#create' do
context 'with valid attributes' do
before do
post :create, { company:{ name:"Albert", domain:"www.albert.com"} }
end
it 'responds with success' do
expect(response.status).to eq(302)
end
it 'creates company' do
company = Company.find_by(name: "Albert")
expect(assigns(:company)).to eq(company)
expect(response).to redirect_to(companies_path())
end
end
context 'with invalid attributes' do
before do
post :create, { company:{ name:"", domain:""} }
end
it 'renders new template' do
expect(response).to render_template(:edit)
end
end
end
end
No need to sub anything here. As per my knowledge, Only when we use any lib classes / background jobs / third party libraries code inside action then we need to stub those code. Because for all those, we will write specs separately. So no need to test again here that's why we'll do stubing.
Thanks to Narsimha Reddy, I have better ideas about how to test.
Eventhough, if I want to stub
#company=Company.new(company_params)
#company.user=helpers.user
if #company.save()
For testing only de create's response , the solution was in a good use of parameters, and allowing allow(company).to receive(:user=) for the belongs_to association
let(:company_params) {{company:{name:"Albert",domain:"www.albert.com"}}}
let(:ac_company_params) {ActionController::Parameters.new(company_params).require(:company).permit!}
let(:company) { instance_double(Company) }
before do
allow(Company).to receive(:new){company}
allow(company).to receive(:user=)
allow(company).to receive(:save){true}
end
it "redirects to companies_path" do
expect(Company).to receive(:new).with(ac_company_params)
expect(company).to receive(:user=).with(user)
post :create, params: company_params
expect(response).to redirect_to(companies_path)
end

Testing Controllers in Rails 4

I am looking for clarification and an understanding on how to effectively test my controllers with Rspec, I don't want to write tests that are not testing the potential issues at hand.
My scenario is as follows.
I am using Active Admin to create a Category, to do so you must obviously be logged into Active Admin.
What I want to ensure is that
1) A logged in user can create a Category
2) A Category cannot be created if you are not logged in
3) Attempts to create a Category outside of active admin are met with a 404 template
So what i have so far (and i really want to check i haven't gone over the top or performing unnecessary tests) is as follows.
spec/controllers/categories_controller_spec.rb
require 'rails_helper'
include Warden::Test::Helpers
# Ensure 404 pages are returned when requesting URLS
RSpec.describe CategoriesController, type: :request do
describe 'Routes' do
context 'All CRUD actions render 404' do
it '#create' do
post '/categories'
expect(response.status).to eq(404)
expect(response).to render_template(:file => "#{Rails.root}/public/404.html.erb")
end
# All other actions here
end
end
end
RSpec.describe Admin::CategoriesController, type: :request do
describe 'No Authorised Login' do
context 'All CRUD actions redirect correctly' do
it 'redirects when accessing #index' do
get '/admin/categories'
expect(response.status).to eq(302)
expect(response).to redirect_to(admin_root_path + '/login')
end
# All other actions here
end
end
end
# Ensure actions in admin can be carried out if logged in
RSpec.describe Admin::CategoriesController, type: :request do
before(:each) do
#user = FactoryGirl.create(:admin_user)
login_as #user
end
after(:each) do
#user.destroy
end
describe 'Authorised Login' do
context 'All CRUD actions perform as expected' do
it 'navigates to Categories #index' do
get '/my_admin_panel/categories'
expect(response.status).to eq(200)
expect(response).to render_template(:index)
end
# All other actions here
end
end
spec/routing/categories_routing.spec
RSpec.describe CategoriesController, type: :routing do
describe 'Routes' do
it 'does not get #index' do
expect(get: '/categories').to route_to(
controller: 'application',
action: 'raise_not_found',
unmatched_route: 'categories'
)
end
end
end
Should I be testing post /categories without supplying params, is that a wasted test? Am I over complicating what should be a simple set of tests ?
This is a judgement/style question and, as such, is not ideal for the StackOverflow format. That said, I don't think your testing is over the top. Some other thoughts:
Some people choose treat their controller tests as integration tests.
You can take advantage of RSpec's shared examples to DRY up your tests
In the default RSpec configuration, the database will be cleaned after each test, so you don't need to explicitly destroy the ActiveRecord objects you create if it's the database you're worried about
In general, I think testing behavior for programmatic actions you don't expect to happen (e.g. posting to undefined routes) is worthwhile unless you are trying to test specific error handling code

I'm DRYing my specs, but have a issue with making dynamic requests for controller tests

I was noticing that I kept repeating the same spec for actions prohibited to certain users. Especially when the action is not allowed, the redirect and flash should always be the same (more or less), so I tried writing a shared_example like this:
shared_examples_for "no access" do |action|
it "redirects the user to the homepage" do
get action
subject.should redirect_to('/')
end
it "sets a flash message" do
get action
expect(controller).to set_flash[:alert]
end
end
But then quickly realised that get doesn't accept the action variable as a variable.
Any idea on fixing this, or achieving something like this some other way?
Specify your shared example as follows...
shared_examples "no access" do
it "redirects the user to the homepage" do
action
expect(response).to redirect_to('/')
end
end
Then in your tests you pass action as a let block...
it_behaves_like "no access" do
let(:action) {get :show, id: my_record.id}
end

Avoid excessive rspec nesting with subject, let, and alternative arguments

I'm trying to do some model_spec testing but having trouble with not having to further nest my rspec code. It would be great if in this case, I could just have a set of "it's" instead of having to add context everytime I want to switch the variable var. Here's the following code:
describe "#some_method" do
subject { course.some_method(var) }
context 'given a project' do
let(:var) {random[1]}
it 'returns the one after' do
is_expected.to eq(random[2])
end
context 'being the last' do
let(:vars) {random.last}
it 'returns nil' do
is_expected.to be_nil
end
end
context '...you get the point, being something else' do
let(:vars) { something.else }
it 'returns nil' do
is_expected.to.to be_nil
end
end
end
end
Maybe I'm just stuck in the wrong mode of thinking and someone could think of a better way for me to do this? I've been suggested that I absolutely must use the subject by someone I work for.
At first, I disagreed and thought it was getting a little burdensome but then I figured keeping subject and having let(:var) apply to it was pretty useful...
RSpecs subject is a tool which can be used to make tests more succinct. There are many cases where it makes sense to use the subject:
RSpec.describe User do
# with the help of shoulda-matchers
it { should validate_uniqueness_of :username } # implicit subject
end
RSpec.describe UsersController do
describe '#show' do
it 'is successful' do
get :show
expect(response).to have_http_status :success
end
it 'renders template show' do
get :show
expect(response).to render_template :show
end
end
#vs
describe '#show' do
subject { response }
before { get :show }
it { should have_http_status :success }
it { should render_template :success }
end
end
And there are cases where using subject will hurt the readability and acuity of your tests.
Your college is just plain wrong in insisting that you always use subject.
A good rule of hand is that if you need an it block then you should not be using subject or is_expected.
If you are describing the call signature of a method you should be calling it in your specs in the same way you would in real life.
let(:decorator){ described_class.new(user) }
describe "#link" do
it 'takes a class option' do
expect(decorator.link(class: 'button')).to match /class=\"button/
end
end
I would recommend running rspec with the --format documentation option and checking if the output actually makes sense. This can be quite important once you get 100s of specs as it gets harder to remember what a behavior a spec actually covers.
How about you write it like this?
expect(subject.call(foo)) is not very pretty but it gets rid of the nesting.
describe "#some_method" do
subject { course.method(:some_method) }
it 'returns the one after if given a project' do
expect(subject.call(random[1])).to eq(random[2])
end
it 'returns nil when it is the last' do
expect(subject.call(random.last)).to be_nil
end
it 'returns nil...' do
expect(subject.call(something.else)).to be_nil
end
end

Mocking and stubbing in testing

I've recently learned how to stub in rspec and found that some benefits of it are we can decouple the code (eg. controller and model), more efficient test execution (eg. stubbing database call).
However I figured that if we stub, the code can be tightly tied to a particular implementation which therefore sacrifice the way we refactor the code later.
Example:
UsersController
# /app/controllers/users_controller.rb
class UsersController < ApplicationController
def create
User.create(name: params[:name])
end
end
Controller spec
# /spec/controllers/users_controller_spec.rb
RSpec.describe UsersController, :type => :controller do
describe "POST 'create'" do
it 'saves new user' do
expect(User).to receive(:create)
post :create, :name => "abc"
end
end
end
By doing that didn't I just limit the implementation to only using User.create? So later if I change the code my test will fail even though the purpose of both code is the same which is to save the new user to database
# /app/controllers/users_controller.rb
class UsersController < ApplicationController
def create
#user = User.new
#user.name = params[:name]
#user.save!
end
end
Whereas if I test the controller without stubbing, I can create a real record and later check against the record in the database. As long as the controller is able to save the user Like so
RSpec.describe UsersController, :type => :controller do
describe "POST 'create'" do
it 'saves new user' do
post :create, :name => "abc"
user = User.first
expect(user.name).to eql("abc")
end
end
end
Really sorry if the codes don't look right or have errors, I didn't check the code but you get my point.
So my question is, can we mock/stub without having to be tied to a particular implementation? If so, would you please throw me an example in rspec
You should use mocking and stubbing to simulate services external to the code, which it uses, but you are not interested in them running in your test.
For example, say your code is using the twitter gem:
status = client.status(my_client)
In your test, you don't really want your code to go to twitter API and get your bogus client's status! Instead you stub that method:
expect(client).to receive(:status).with(my_client).and_return("this is my status!")
Now you can safely check your code, with deterministic, short running results!
This is one use case where stubs and mocks are useful, there are more. Of course, like any other tool, they may be abused, and cause pain later on.
Internally create calls save and new
def create(attributes = nil, options = {}, &block)
if attributes.is_a?(Array)
attributes.collect { |attr| create(attr, options, &block) }
else
object = new(attributes, options, &block)
object.save
object
end
end
So possibly your second test would cover both cases.
It is not straight forward to write tests which are implementation independent. That's why integration tests have a lot of value and are better suited than unit tests for testing the behavior of the application.
In the code you're presented, you're not exactly mocking or stubbing. Let's take a look at the first spec:
RSpec.describe UsersController, :type => :controller do
describe "POST 'create'" do
it 'saves new user' do
expect(User).to receive(:create)
post :create, :name => "abc"
end
end
end
Here, you're testing that User received the 'create' message. You're right that there's something wrong with this test because it's going to break if you change the implementation of the controllers 'create' action, which defeats the purpose of testing. Tests should be flexible to change and not a hinderance.
What you want to do is not test implementation, but side effects. What is the controller 'create' action supposed to do? It's supposed to create a user. Here's how I would test it
# /spec/controllers/users_controller_spec.rb
RSpec.describe UsersController, :type => :controller do
describe "POST 'create'" do
it 'saves new user' do
expect { post :create, name: 'abc' }.to change(User, :count).by(1)
end
end
end
As for mocking and stubbing, I try to stay away from too much stubbing. I think it's super useful when you're trying to test conditionals. Here's an example:
# /app/controllers/users_controller.rb
class UsersController < ApplicationController
def create
user = User.new(user_params)
if user.save
flash[:success] = 'User created'
redirect_to root_path
else
flash[:error] = 'Something went wrong'
render 'new'
end
end
# /spec/controllers/users_controller_spec.rb
RSpec.describe UsersController, :type => :controller do
describe "POST 'create'" do
it "renders new if didn't save" do
User.any_instance.stub(:save).and_return(false)
post :create, name: 'abc'
expect(response).to render_template('new')
end
end
end
Here I'm stubbing out 'save' and returning 'false' so I can test what's supposed to happen if the user fails to save.
Also, the other answers were correct in saying that you want to stub out external services so you don't call on their API every time you're running your test suite.

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