rails+rspec controller spec with polymorphic association - ruby-on-rails

Question

I'm trying to test the actions in controller spec but for some reason I get the no routes matches error. What should I do to make the route work?
ActionController::UrlGenerationError:
No route matches {:action=>"create", :comment=>{:body=>"Consectetur quo accusamus ea.",
:commentable=>"4"}, :controller=>"comments", :post_id=>"4"}
model
class Comment < ActiveRecord::Base
belongs_to :commentable, polymorphic: true, touch: true
class Post < ActiveRecord::Base
has_many :comments, as: :commentable, dependent: :destroy
routes
resources :posts do
resources :comments, only: [:create, :update, :destroy], module: :posts
end
controller_spec
describe "POST create" do
let!(:user) { create(:user) }
let!(:profile) { create(:profile, user: #user) }
let!(:commentable) { create(:post, user: #user) }
context "with valid attributes" do
subject(:create_action) { xhr :post, :create, post_id: commentable, comment: attributes_for(:comment, commentable: commentable, user: #user) }
it "saves the new task in the db" do
expect{ create_action }.to change{ Comment.count }.by(1)
end
...
EDIT
The controller_spec from above can be found in spec/controllers/comments_controller_spec.rb
controllers/comments_controller.rb
class CommentsController < ApplicationController
before_action :authenticate_user!
def create
#comment = #commentable.comments.new(comment_params)
authorize #comment
#comment.user = current_user
if #comment.save
#comment.send_comment_creation_notification(#commentable)
respond_to :js
end
end
controllers/posts/comments_controller.rb
class Posts::CommentsController < CommentsController
before_action :set_commentable
private
def set_commentable
#commentable = Post.find(params[:post_id])
end

Answer 1

Using the module: :posts will route to Posts::CommentsController#create.
If that is not what you intended than remove the module option.
Otherwise you need to ensure that you have the correct class name for both your controller and spec.
class Posts::CommentsController
def create
end
end
RSpec.describe Posts::CommentsController do
# ...
end
Also note that if often does not make sense to nest the "individual actions" for a resource.
Instead you may want to declare the routes like so:
resources :comments, only: [:update, :destroy] # show, edit ...
resources :posts do
resources :comments, only: [:create], module: :posts # new, index
end
Which gives you:
class CommentsController < ApplicationController
before_action :set_posts
# DELETE /comments/:id
def destroy
# ...
end
# PUT|PATCH /comments/:id
def update
end
end
class Posts::CommentsController < ApplicationController
# POST /posts/:post_id/comments
def create
# ...
end
end
See Avoid Deeply Nested Routes in Rails for a deeper explaination of why.
Setting the up the controller to use inheritance in this case is a good idea - however you cannot test the create method through the parent CommentsController class in a controller spec since RSpec will always look at described_class when trying to resolve the route.
Instead you may want to use shared examples:
# /spec/support/shared_examples/comments.rb
RSpec.shared_examples "nested comments controller" do |parameter|
describe "POST create" do
let!(:user) { create(:user) }
context "with valid attributes" do
subject(:create_action) { xhr :post, :create, post_id: commentable, comment: attributes_for(:comment, commentable: commentable, user: #user) }
it "saves the new task in the db" do
expect{ create_action }.to change{ Comment.count }.by(1)
end
end
end
end
require 'rails_helper'
require 'shared_examples/comments'
RSpec.describe Posts::CommentsController
# ...
include_examples "nested comments controller" do
let(:commentable) { create(:post, ...) }
end
end
require 'rails_helper'
require 'shared_examples/comments'
RSpec.describe Products::CommentsController
# ...
include_examples "nested comments controller" do
let(:commentable) { create(:product, ...) }
end
end
The other alternative which I prefer is to use request specs instead:
require 'rails_helper'
RSpec.describe "Comments", type: :request do
RSpec.shared_example "has nested comments" do
let(:path) { polymorphic_path(commentable) + "/comments" }
let(:params) { attributes_for(:comment) }
describe "POST create" do
expect do
xhr :post, path, params
end.to change(commentable.comments, :count).by(1)
end
end
context "Posts" do
include_examples "has nested comments" do
let(:commentable) { create(:post) }
end
end
context "Products" do
include_examples "has nested comments" do
let(:commentable) { create(:product) }
end
end
end
Since you are really sending a HTTP request instead of faking it they cover more of the application stack. This does however come with a small price in terms of test speed. Both shared_context and shared_examples are two of the things which make RSpec really awesome.