```ruby
require 'rails_helper'

RSpec.describe Comment, type: :controller do

  let(:duck_user1) { double("User", name: "Daffy", password_digest: "123")}
  let(:duck_user2) { double("User", name: "Plucky", password_digest: "123")}
  let(:duck_question) { double("Question", title: "Does it quack?",
                                           content: "I have a duck I need to assess.",
                                           user: :duck_user1)}
  let(:duck_answer) { double("Answer", content: "It quacks.",
                                       user: :duck_user2)}

  it 'creates a new comment that knows precisely which Question or Answer it is a response to'
    duck_params = {
      commentable_id: duck_question.id
      commentable_type: "Question",
      content: "I like ducks.",
      user_id: duck_user.id
    }
    # This isn't really what we need to test:
    expect {
      post :create, duck_params
    }.to change{Comment.count}.by(1)
  end

end
```

Comment out comments_controller spec file
user
```ruby
# require 'rails_helper'

# RSpec.describe Comment, type: :controller do

#   let(:duck_user1) { double("User", name: "Daffy", password_digest: "123")}
#   let(:duck_user2) { double("User", name: "Plucky", password_digest: "123")}
#   let(:duck_question) { double("Question", title: "Does it quack?",
#                                            content: "I have a duck I need to assess.",
#                                            user: :duck_user1)}
#   let(:duck_answer) { double("Answer", content: "It quacks.",
#                                        user: :duck_user2)}

#   it 'creates a new comment that knows precisely which Question or Answer it is a response to'
#     duck_params = {
#       commentable_id: duck_question.id
#       commentable_type: "Question",
#       content: "I like ducks.",
#       user_id: duck_user.id
#     }
#     # This isn't really what we need to test:
#     expect {
#       post :create, duck_params
#     }.to change{Comment.count}.by(1)
#   end

# end
```
assistant