ability_spec.rb

require 'rails_helper'

RSpec.describe Ability do
  subject(:ability) { Ability.new(user) }

  describe "for guest" do
    let(:user) { nil }

    it { should be_able_to :read, :all }
    it { should_not be_able_to :manage, :all }
  end

  describe "for user" do
    let(:user) { create :user }
    let(:other) { create :user }

    it { should be_able_to :read, :all }
    it { should_not be_able_to :manage, :all }

    context "user" do
      let(:question) { create :question, user: other }
      let(:answer) { create :answer, question: question, user: other }
      let(:comment) { create :comment, user: other, commentable: question }
      let(:attachment) { create :attachment, attachable: question }

      it { should be_able_to :create, Question }
      it { should be_able_to :create, Answer }
      it { should be_able_to :create, Attachment }
      it { should be_able_to :create, Comment }

      it { should_not be_able_to %i[update destroy], question, user_id: user.id }
      it { should_not be_able_to %i[update destroy], answer, user_id: user.id }
      it { should_not be_able_to :destroy, comment, user_id: user.id }
      it { should_not be_able_to :set_best, answer, user_id: user.id }
      it { should_not be_able_to :destroy, attachment, user_id: user.id }
    end

    context "author" do
      let(:question) { create :question, user: user }
      let(:answer) { create :answer, question: question, user: user }
      let(:other_answer) { create :answer, question: question, user: other }
      let(:comment) { create :comment, user: user, commentable: question }
      let(:attachment) { create :attachment, attachable: question }

      it { should be_able_to %i[update destroy], question, user_id: user.id }
      it { should be_able_to %i[update destroy], answer, user_id: user.id }
      it { should be_able_to :destroy, comment, user_id: user.id }
      it { should be_able_to :set_best, other_answer, user_id: user.id }
      it { should be_able_to :destroy, attachment, user_id: user.id }
    end

    context "vote" do
      let(:question) { create :question, user: user }
      let(:other_question) { create :question, user: other }
      let(:vote) { create :vote, user: user, votable: question }
      let(:other_vote) { create :vote, user: other, votable: other_question }

      it {
        should be_able_to(
          %i[vote_up vote_down],
          # можно ли здесь использовать new, а не create, чтобы не все атрибуты вводить?
          other_question.votes.new(votable: other_question)
        )
      }

      it {
        should_not be_able_to(
          %i[vote_up vote_down],
          question.votes.new(votable: question)
        )
      }

      it { should be_able_to :cancel_vote, vote, user_id: user.id }
      it { should_not be_able_to :cancel_vote, other_vote, user_id: user.id }
    end
  end
end