answers_controller_spec.rb

require 'rails_helper'

RSpec.describe AnswersController, type: :controller do
  sign_in_user
  let(:question) { create(:question) }
  let(:answer) { create(:answer, question: question) }

  describe 'DELETE #destroy' do
    before { answer }

    context "1) user deletes his answer" do
      it 'deletes users answer' do
        
        expect { delete :destroy, params: { question_id: question, id: answer } }
        .to change(Answer, :count).by(-1)
      end

      it 'redirects to question' do
        delete :destroy, params: { question_id: question, id: answer }

        expect(response).to be_successful
      end
    end

  context '2) user tries to delete an answer which he is not the author of' do
    let(:answer) { create(:answer, question: question) }

    it 'does not delete the answer' do
      expect { delete :destroy, params: { question_id: question, id: answer } }
      .to_not change(Answer, :count)
    end
  end
end

  describe 'POST #create' do
    context '1) with valid attributes' do

      it 'saves new users answer to the db' do
        expect { post :create, params: { question_id: question, answer: attributes_for(:answer) } }.to change(question.answers, :count).by(1)
      end

      it 'creates and saves new answer to db for a logged in user' do
        expect { post :create, params: { question_id: question.id, answer: attributes_for(:answer) } }.to change(@user.answers, :count).by(1)
      end

      it 'redirects to show view of a question' do
        post :create, params: { question_id: question,
                                answer: attributes_for(:answer) }
        expect(response).to redirect_to question_path(question)
      end
    end

    context '2) with invalid attributes' do
      it 'does not save new anwser to db' do
        expect { post :create, params: { question_id: question,
                 answer: attributes_for(:invalid_answer) } }.to_not change(Answer, :count)
      end

      it 're-renders new view' do
        post :create, params: { question_id: question,
                                answer: attributes_for(:invalid_answer) }
        expect(response).to render_template 'questions/show'
      end
    end
  end

end