Tips and Tricks for writing Rails Controller tests with RSpec and Factory Girl

1. Controller Specs
Xander Miller
@pareidoliax

2. What is Controller
Testing?

3. Why Controller Test?

4. Tools

5. RSpec
FactoryGirl

6. General RSpec Tips

7. RSpec Tips
• Configuration: Color, Verbose
• Alias bundle exec
• description text should build the user story
• add comments to your end statements

8. Configuration
~/.rspec
--require spec_helper
--color
--format documentation
bundle install --no-rdoc

9. Alias Bundle exec
alias brspec="bundle exec rspec"
alias be="bundle exec"

10. Description Text builds a User
Story
TagsController
when authorized User (admin)
the DELETE #destroy action
behaves like a 302 redirect request action
redirects to :back (root_path)

11. RSpec Gotchas

12. RSPec Gotchas
• Scoping is weird
it_behaves_like "a 302 redirect request action", ":back (root_path)" do
let!(:put_update) {put :update, id: @user.id, user: @user_attributes}
let(:redirect_path) {root_path}
end
• Relish Docs

13. How to RSpec

14. How to RSpec
OO BB Object Oriented Black Box
• Given (Context)
• When (Event)
• Then (Expected Result)

15. Applying it to
Controllers

16. Given
• Session
• Domain Object Layer status
• Params

17. When
• HTTP Request with Params

18. Then
• Flash Messages
• Assigns Instance Variables (decorators)
• Domain Object Layer Changes

19. Keeping it DRY
• before Hooks (given)
• let (when)
• shared examples

20. before :example
before :example do
@admin = create(:admin)
session[:user_id] = @admin.id
end

21. let :example
let!(:post_create) {post :create, user: @user_attributes}
let(:redirect_path) {root_path}

22. shared examples: 3 types of
RESTful responses
• successful GET action
• redirect 302 action
• unauthorized action 302 redirect

23. successful GET action
RSpec.shared_examples_for 'an unauthorized action' do
it "responds redirect with an HTTP 302 status code" do
expect(response).to be_redirect
expect(response).to have_http_status(:found)
end
it "provides a flash alert message" do
expect(flash[:warning]).to_not be_nil
end
it "redirects to login_path" do
expect(response).to redirect_to login_path
end
end

24. redirect 302 action
RSpec.shared_examples_for "a 302 redirect request action" do |path_name|
it "responds with a redirect HTTP 302 status code" do
expect(response).to be_redirect
expect(response).to have_http_status(:found)
end
it "redirects to #{path_name}" do
expect(response).to redirect_to redirect_path
end
end

25. unauthorized action 302 redirect
RSpec.shared_examples_for 'an unauthorized action' do
it "responds redirect with an HTTP 302 status code" do
expect(response).to be_redirect
expect(response).to have_http_status(:found)
end
it "provides a flash alert message" do
expect(flash[:warning]).to_not be_nil
end
it "redirects to login_path" do
expect(response).to redirect_to login_path
end
end

26. Overall Structure of a
Controller Spec

27. require 'support/controller_helper'
describe UsersController do
context 'when unauthorized (no User)' do
describe "the GET #new action" do
end # describe "the GET #new action" do
describe "the POST #create action" do
context "is provided valid User params and" do
end # context "is provided valid User params and" do
context "is provided invalid User params and" do
end # context "is provided invalid User params and" do
end # describe "the POST #create action" do
describe "the GET #show action" do
end # describe "the GET #show action" do
end # context 'when unauthorized (no User signed in)' do

28. context 'when authorized (Admin User)' do
describe "the GET #index action" do
end #describe "the GET #index action" do
describe "the PUT #update action" do
context "is provided valid user params and" do
end # "is provided valid user params and" do
context "is provided invalid user params and" do
end # "is provided invalid user params and" do
end # "the PUT #update action" do
end # context 'when authorized (Admin User)' do
end

29. Example Specs

30. Unauthorized Action
describe "the GET #show action" do
before :example do
@user = create(:user)
end
it_behaves_like 'an unauthorized action' do
let!(:get_show) {get :show, {id: @user.id}}
end
end # describe "the GET #show action" do

31. Examples by RESTful
Action

32. GET #show
describe "the GET #show action" do
before :example do
@user = create(:user)
end
it_behaves_like "a successful GET action", :show do
let!(:get_show) {get :show, {id: @user.id}}
end
let(:get_show) {get :show, {id: @user.id}}
it "assigns a valid UserDecorator of to @user" do
get_show
@decorated_user = UserDecorator.new @user
expect(assigns(:user)).to be_kind_of(UserDecorator)
expect(assigns(:user)).to eq(@decorated_user)
end
end # describe "the GET #show action" do

33. GET #index
describe "the GET #index action" do
it_behaves_like "a successful GET action", :index do
let!(:get_index) {get :index}
end
let(:get_index) {get :index}

34. GET #index con'd
it "loads the users in the current users, current region" do
region = create(:region)
user1, user2 = create(:user), create(:user)
[@admin, user1, user2].each do |u|
u.add_to_region! region
u.current_region = region
u.save
end
get_index
expect(assigns(:users)).to
match_array([@admin.reload, user1.reload, user2.reload])
end
end #describe "the GET #index action" do

35. GET #new
describe "the GET #new action" do
it_behaves_like "a successful GET action", :new do
let!(:get_new) {get :new}
end
let!(:get_new) {get :new}
it "assigns a unsaved User to @user" do
expect(assigns(:user)).to be_kind_of(User)
expect(assigns(:user)).to respond_to(:id).with(nil)
end
end # describe "the GET #new action" do

36. POST #create
describe "the POST #create action" do
before :example do
@user_attributes = attributes_for(:user)
request.env["HTTP_REFERER"] = root_path
end
let(:post_create) {post :create, user: @user_attributes}

37. POST #create con't
context "is provided valid User params and" do
it_behaves_like "a 302 redirect request action", ':back (to root_path)' do
let!(:post_create) {post :create, user: @user_attributes}
let(:redirect_path) {root_path}
end
it "creates a user" do
expect { post_create }.to change(User, :count).by(1)
end
it "provides a flash success message" do
post_create
expect(flash[:success]).to_not be_nil
end
end # context "is provided valid User params and" do

38. POST #create con't con't
context "is provided invalid User params and" do
before :example do
@user_attributes = attributes_for(:user)
User.create @user_attributes
end
it_behaves_like "a 302 redirect request action", 'new_user_path' do
let!(:post_create) {post :create, user: @user_attributes}
let(:redirect_path) {new_user_path}
end
it "fails to create a new user" do
expect { post :create, user: @user_attributes }.not_to change(User, :count)
end
it "provides a flash danger message" do
post_create
expect(flash[:danger]).to_not be_nil
end
end # context "is provided invalid User params and" do
end # describe "the POST #create action" do

39. GET #edit
describe "the GET #edit action" do
before :example do
@user = create(:user)
end
it_behaves_like "a successful GET action", :edit do
let!(:get_edit) {get :edit, {id: @user.id}}
end
let(:get_edit) {get :edit, {id: @user.id}}
it "loads all of the roles from User class into @roles" do
roler = class_double("User")
allow(roler).to receive(:roles).and_return([:worker, :manager, :organizer, :moderator, :admin])
get_edit
expect(assigns(:roles)).to match_array([:worker, :manager, :organizer, :moderator, :admin])
end

40. GET #edit c
on't
it "loads all of the regions from Region class into @regions" do
region1, region2 = create(:region), create(:region)
get_edit
expect(assigns(:regions)).to match_array([region1, region2])
end
it "assigns valid UserDecorator to @user" do
get_edit
@decorated_user = UserDecorator.new @user
expect(assigns(:user)).to be_kind_of(UserDecorator)
expect(assigns(:user)).to eq(@decorated_user)
end
end # describe "the GET #edit action" do

41. PATCH #update
describe "the PUT #update action" do
let(:put_update) {put :update, id: @user.id, user: @user_attributes}
context "is provided valid user params and" do
before :example do
@user_attributes = attributes_for(:user).merge({email: "vengeful_spirit@example.com"})
@user = User.create @user_attributes.merge({email: "sneaky_jugger@example.com"})
end
it_behaves_like "a 302 redirect request action", "@user" do
let!(:put_update) {put :update, id: @user.id, user: @user_attributes}
let(:redirect_path) {@user}
end

42. PATCH #update con't
it "changes user email attribute" do
expect(@user.reload.email).to eq("sneaky_jugger@example.com")
put_update
expect(@user.reload.email).to eq("vengeful_spirit@example.com")
end
it "provides a flash success message" do
put_update
expect(flash[:success]).to_not be_nil
end
end # "is provided valid user params and" do

43. PATCH #update con't con't
context "is provided invalid user params and" do
before :example do
@user_attributes = attributes_for(:user).merge({email: "vengeful_spirit.example.com"})
@user = User.create @user_attributes.merge({email: "sneaky_jugger@example.com"})
request.env["HTTP_REFERER"] = root_path
end
it_behaves_like "a 302 redirect request action", ":back (root_path)" do
let!(:put_update) {put :update, id: @user.id, user: @user_attributes}
let(:redirect_path) {root_path}
end

44. PATCH #update con't con't con't
it "fails to change user email attribute" do
expect(@user.reload.email).to eq("sneaky_jugger@example.com")
put_update
expect(@user.reload.email).to eq("sneaky_jugger@example.com")
end
it "provides a flash danger message" do
put_update
expect(flash[:danger]).to_not be_nil
end
end # "is provided invalid user params and" do
end # "the PUT #update action" do

45. DELETE #destroy
describe "the DELETE #destroy action" do
before :example do
@tag = create(:tag)
request.env["HTTP_REFERER"] = tags_path
end
let(:delete_destroy) {delete :destroy, id: @tag.id }
it "destroys @tag" do
expect {delete_destroy}.to change(Tag, :count).by(-1)
end
it_behaves_like "a 302 redirect request action", "tags_path (:back)" do
let!(:delete_destroy) {delete :destroy, id: @tag.id }
let(:redirect_path) {tags_path}
end
end

46. Resources
• Everyday Rails: How I learned to test my Rails applications
• Relish: RSpec Docs
• Code School: Testing with RSpec
• Code Examples

47. That's all Folks!
@pareidoliax
xandermiller.ca
xander.miller@gmail.com