pokemon.trade/spec/controllers/pokemon_controller_spec.rb

require 'rails_helper'

RSpec.describe PokemonController, type: :controller do
  describe "DELETE #destroy" do
    let!(:pokemon) { FactoryBot.create(:pokemon) }
    subject { delete :destroy, params: {id: pokemon.id} }

    context "the pokemon is successfully deleted" do
      it 'deletes the pokemon' do
        expect{subject}.to change{Pokemon.count}.by(-1)
        expect(response).to redirect_to pokemon_index_path
      end
    end

    context "the pokemon is not deleted" do
      before { allow_any_instance_of(Pokemon).to receive(:destroy).and_return(false) }

      it 'does not delete the pokemon' do
        expect{subject}.to change{Pokemon.count}.by(0)
        expect(response).to render_template :show
      end
    end
  end

  describe "POST #upload" do
    subject { post :upload, params: {pokemon: double()} }
    let(:pokemon) { double(pokedex_number: 10, nickname: "pyukuchu", to_h: {pokedex_number: 10, nickname: "pyukuchu"}) }
    let(:client_response) { double(pokemon: [pokemon]) }

    before do
      allow_any_instance_of(PKParse::Client).to receive(:parse).and_return(client_response)
    end

    context 'parsing succeeds' do
      context 'committing result to database fails' do
        before { allow(Pokemon).to receive(:create!).and_raise(ActiveRecord::ActiveRecordError.new) }

        it 'does not create any new pokemon' do
          #expect{subject}.to raise_error 'canned failure'
          expect{(subject rescue nil)}.to change{Pokemon.count}.by(0)
          expect(response).to render_template :new
        end
      end

      context 'committing result to database succeeds' do
        before do
          allow_any_instance_of(PKParse::Client).to receive(:parse).and_return(client_response)
        end

        it 'creates some new pokemon' do
          expect{subject}.to change{Pokemon.count}.by(1)
          expect(response).to redirect_to pokemon_index_path
        end
      end

    end

    context 'parsing fails' do
      before do
        allow_any_instance_of(PKParse::Client).to receive(:parse).and_raise(PKParse::Error.new(StandardError.new))
      end

      it 'does not create any new pokemon' do
        expect{subject}.to change{Pokemon.count}.by(0)
        expect(controller.flash.now["alert"]).not_to be_empty
        expect(response).to render_template :new
      end
    end
  end
end