fluke/devops-service/spec/executors/server_executor_spec.rb

require 'lib/executors/server_executor'

RSpec.describe Devops::Executor::ServerExecutor, type: :executor, stubbed_connector: true, stubbed_logger: true do
  let(:project) { build(:project) }
  let(:deploy_env) { project.deploy_env('foo') }
  let(:server) { build(:server, project: project.id, deploy_env: 'foo') }
  let(:output) { File.open(File::NULL, "w") }
  let(:provider) { double('Provider instance') }
  let(:executor) { described_class.new(server, output) }


  before do
    allow(stubbed_connector).to receive(:project) { project }
    allow(executor.deploy_env).to receive(:provider_instance) { provider }
    allow(server).to receive(:provider_instance) { provider }
  end

  describe '#initialize' do
    it 'sets server, project, deploy_env, out instance variables' do
      expect(executor.server).to eq server
      expect(executor.deploy_env).to eq deploy_env
      expect(executor).to have_instance_variable_value(:project, project)
      expect(executor).to have_instance_variable_value(:out, output)
    end

    it 'defines :flush method on @out if it is absent' do
      out = Class.new.new
      expect(out).not_to respond_to(:flush)
      described_class.new(server, out)
      expect(out).to respond_to(:flush)
    end

    it 'sets current_user from options' do
      user = double
      executor = described_class.new(server, '', {current_user: user})
      expect(executor).to have_instance_variable_value(:current_user, user)
    end
  end


  describe '#report=' do
    it 'sets report instance variable' do
      executor.report= 'foo'
      expect(executor).to have_instance_variable_value(:report, 'foo')
    end
  end

  describe '#project=' do
    it 'sets project instance variable' do
      executor.project= 'foo'
      expect(executor).to have_instance_variable_value(:project, 'foo')
    end
  end


  describe '.reason_from_error_code' do
    it 'returns symbol given an integer' do
      expect(described_class.reason_from_error_code(2)).to eq :server_bootstrap_fail
    end

    it "returns :unknown_error if can't recognize error code" do
      expect(described_class.reason_from_error_code(123)).to eq :unknown_error
    end
  end



  describe '#create_server_object' do
    it 'builds Server object' do
      server = executor.create_server_object('created_by' => 'me')
      expect(server).to be_a(Devops::Model::Server)
      expect(server.project).to eq 'my_project'
      expect(server.deploy_env).to eq 'foo'
      expect(server.created_by).to eq 'me'
    end
  end



  describe '#create_server' do
    let(:image) { double('Image instance', remote_user: 'remote_user') }
    let(:create_server) {
      executor.create_server(
        'created_by' => 'user',
        'run_list' => @run_list,
        'name' => 'node_name',
        'key' => @key,
        'without_bootstrap' => @without_bootstrap
      )
    }

    before do
      allow(provider).to receive(:create_server) { true }
      allow(stubbed_connector).to receive(:image) { image }
      allow(stubbed_connector).to receive(:server_insert)
      @without_bootstrap = true
      @run_list = %w(role[asd])
      @key = 'key'
    end

    it 'builds server model from given options' do
      create_server
      expect(executor.server.created_by).to eq 'user'
      expect(executor.server.chef_node_name).to eq 'node_name'
      expect(executor.server.key).to eq @key
      expect(executor.server.run_list).to eq @run_list
    end

    it 'sets run list to an empty array by default' do
      @run_list = nil
      create_server
      expect(executor.server.run_list).to eq []
    end

    it 'sets key to default provider ssh key by default' do
      @key = nil
      allow(provider).to receive(:ssh_key) { 'default_key' }
      create_server
      expect(executor.server.key).to eq 'default_key'
    end

    it 'runs hooks' do
      expect(executor).to receive(:run_hook).with(:before_create).ordered
      expect(executor).to receive(:run_hook).with(:after_create).ordered
      create_server
    end

    it 'creates server in cloud' do
      expect(provider).to receive(:create_server).with(
        an_instance_of(Devops::Model::Server), deploy_env.image, deploy_env.flavor, deploy_env.subnets, deploy_env.groups, output
      )
      create_server
    end

    it 'inserts built server into mongo' do
      expect(stubbed_connector).to receive(:server_insert)
      create_server
    end

    it 'schedules expiration for server' do
      deploy_env.expires = '2m'
      allow(DeleteExpiredServerWorker).to receive(:perform_in)
      expect(DeleteExpiredServerWorker).to receive(:perform_in).with(120, hash_including(:server_id))
      create_server
    end

    it "doesn't schedule expiration if deploy_env.expires is nil" do
      deploy_env.expires = nil
      expect(DeleteExpiredServerWorker).not_to receive(:perform_in)
      create_server
    end

    context 'without_bootstrap option is false' do
      it 'launches bootstrap' do
        @without_bootstrap = false
        allow(image).to receive(:bootstrap_template) { 'template' }
        allow(executor).to receive(:two_phase_bootstrap)
        expect(executor).to receive(:two_phase_bootstrap)
        create_server
      end
    end

    context 'without_bootstrap option is nil' do
      it 'launches bootstrap' do
        @without_bootstrap = nil
        allow(image).to receive(:bootstrap_template) { 'template' }
        allow(executor).to receive(:two_phase_bootstrap)
        expect(executor).to receive(:two_phase_bootstrap)
        create_server
      end
    end

    context 'without_bootstrap option is true' do
      it "doesn't launch bootstrap" do
        @without_bootstrap = true
        expect(executor).not_to receive(:two_phase_bootstrap)
        create_server
      end
    end

    context 'if error has been raised during execution' do
      before do
        allow(stubbed_connector).to receive(:server_delete)
        allow(provider).to receive(:create_server) { raise }
      end

      it 'rollbacks server creating' do
        expect(executor).to receive(:roll_back)
        create_server
      end

      it 'deletes server from mongo' do
        expect(stubbed_connector).to receive(:server_delete)
        create_server
      end
    end

    context "if creating server in cloud wasn't successful" do
      it 'returns creating_server_in_cloud_failed error code' do
        allow(provider).to receive(:create_server) { false }
        expect(create_server).to eq 10
      end
    end
  end



  describe '#bootstrap', stubbed_knife: true do
    let(:image) { double('Key instance', path: 'path') }
    let(:bootstrap) { executor.bootstrap({}) }

    before do
      allow(executor).to receive(:sleep)
      allow(executor).to receive(:last_command_successful?).and_return(true)
      allow(executor).to receive(:execute_system_command)
      allow(provider).to receive(:create_default_chef_node_name).and_return('chef_node')
      allow(stubbed_connector).to receive(:key).and_return(image)
      allow(stubbed_connector).to receive(:server_set_chef_node_name)
      allow(stubbed_knife).to receive(:knife_bootstrap).and_return(0)
    end

    it 'run before hook' do
      expect(executor).to receive(:run_hook).with(:before_bootstrap, output).ordered
      expect(executor).to receive(:run_hook).with(:after_bootstrap, output).ordered
      bootstrap
    end

    context "when server's private ip is unset" do
      it 'returns server_bootstrap_private_ip_unset error code' do
        server.private_ip = nil
        expect(bootstrap).to eq 4
      end
    end

    it 'tries to ssh to server' do
      expect(executor).to receive(:execute_system_command).with(/ssh/)
      bootstrap
    end

    context "couldn't ssh to server" do
      before { allow(executor).to receive(:last_command_successful?) { false } }

      it 'tries to ssh to server maximum MAX_SSH_RETRIES_AMOUNT times' do
        max_retries = Devops::Executor::ServerExecutor::MAX_SSH_RETRIES_AMOUNT
        expect(executor).to receive(:execute_system_command).exactly(max_retries).times
        bootstrap
      end

      it 'returns server_bootstrap_fail error code' do
        expect(bootstrap).to eq 2
      end
    end


    context 'after successful ssh check' do
      before { allow(executor).to receive(:last_command_successful?).and_return(false, true) }

      it "sets default chef node name if it's nil" do
        executor.server.chef_node_name = nil
        expect {bootstrap}.to change {executor.server.chef_node_name}.to 'chef_node'
      end

      it 'executes knife bootstrap' do
        expect(stubbed_knife).to receive(:knife_bootstrap).with(output, server.private_ip, instance_of(Array))
        bootstrap
      end

      it "bootstraps to public ip if it's set" do
        server.public_ip = '8.8.8.8'
        expect(stubbed_knife).to receive(:knife_bootstrap).with(output, '8.8.8.8', instance_of(Array))
        bootstrap
      end

      context 'after successful bootstrap' do
        it "updates server's chef node name in db" do
          expect(stubbed_connector).to receive(:server_set_chef_node_name).with(instance_of(Devops::Model::Server))
          bootstrap
        end
      end

      context "if bootstraping wasn't successful" do
        before { allow(stubbed_knife).to receive(:knife_bootstrap).and_return(123) }

        it 'returns :server_bootstrap_fail code' do
          expect(bootstrap).to eq 2
        end

        it "doesn't run after hook" do
          expect(executor).to receive(:run_hook).with(:before_bootstrap, output)
          bootstrap
        end
      end
    end
  end



  describe '#two_phase_bootstrap', stubbed_knife: true do
    let(:two_phase_bootstrap) { executor.two_phase_bootstrap({}) }

    before do
      allow(provider).to receive(:run_list) {[]}
      allow(stubbed_connector).to receive(:server_delete)
    end

    context 'when bootstrap was successful' do
      before do
        allow(executor).to receive(:bootstrap) { 0 }
        allow(executor).to receive(:check_server_on_chef_server) { false }
      end

      context 'if node presents on chef server' do
        before do
          allow(executor).to receive(:check_server_on_chef_server) { true }
          allow(executor).to receive(:deploy_server)
          allow(stubbed_knife).to receive(:set_run_list)
        end

        it 'builds run list' do
          expect(executor).to receive(:compute_run_list)
          two_phase_bootstrap
        end

        it 'sets run list to chef node' do
          expect(stubbed_knife).to receive(:set_run_list)
          two_phase_bootstrap
        end

        it 'deploys server' do
          expect(executor).to receive(:deploy_server)
          two_phase_bootstrap
        end

        context 'if deploy was successful' do
          it 'returns 0' do
            allow(executor).to receive(:deploy_server) { 0 }
            expect(two_phase_bootstrap).to eq 0
          end
        end

        context "if deploy wasn't successful" do
          it 'returns :deploy_failed code' do
            allow(executor).to receive(:deploy_server) { 1 }
            expect(two_phase_bootstrap).to eq 8
          end
        end

        context 'when an error occured during deploy' do
          it 'returns :deploy_unknown_error code' do
            allow(executor).to receive(:deploy_server) { raise }
            expect(two_phase_bootstrap).to eq 6
          end
        end
      end

      context "if node doesn't present on chef server" do
        it 'roll backs and then deletes server from mongo' do
          allow(executor).to receive(:check_server_on_chef_server) { false }
          allow(executor).to receive(:roll_back)
          allow(stubbed_connector).to receive(:server_delete)
          expect(executor).to receive(:roll_back).ordered
          expect(stubbed_connector).to receive(:server_delete).ordered
          two_phase_bootstrap
        end
      end
    end

    context "when bootstrap wasn't successful" do
      before do
        allow(executor).to receive(:bootstrap) { 1 }
        allow(executor).to receive(:roll_back)
      end

      it 'returns :server_bootstrap_fail error code' do
        expect(two_phase_bootstrap).to eq 2
      end

      it 'rollbacks server' do
        allow(executor).to receive(:roll_back)
        two_phase_bootstrap
      end
    end

    context 'when an error occured during bootstrap' do
      it 'returns :server_bootstrap_unknown_error error code' do
        allow(executor).to receive(:bootstrap) { raise }
        expect(two_phase_bootstrap).to eq 7
      end
    end
  end

  describe '#check_server_on_chef_server', stubbed_knife: true do
    before do
      server.chef_node_name = 'a'
      allow(stubbed_knife).to receive(:chef_node_list) { @node_list }
      allow(stubbed_knife).to receive(:chef_client_list) { @client_list }
    end

    it 'returns true when node_name in node list and in client list' do
      @node_list = %w(a); @client_list = %w(a)
      expect(executor.check_server_on_chef_server).to be true
    end

    it "returns false if node name isn't in node list" do
      @node_list = []; @client_list = %w(a)
      expect(executor.check_server_on_chef_server).to be false
    end

    it "returns false if node name isn't in node list" do
      @node_list = %w(a); @client_list = []
      expect(executor.check_server_on_chef_server).to be false
    end
  end


  describe '#unbootstrap', stubbed_knife: true do
    before do
      allow(stubbed_connector).to receive_message_chain('key.path') { 'path_to_key' }
      allow(stubbed_knife).to receive(:chef_node_delete)
      allow(stubbed_knife).to receive(:chef_client_delete)
      allow(executor).to receive(:execute_system_command) { '' }
      allow(executor).to receive(:last_command_successful?) { true }
      allow(executor).to receive(:sleep)
      allow(Net::SSH).to receive(:start)
    end

    it 'connects by ssh' do
      expect(Net::SSH).to receive(:start)
      executor.unbootstrap
    end

    it 'returns hash with error after 5 unsuccessful retries' do
      allow(Net::SSH).to receive(:start) { raise }
      expect(Net::SSH).to receive(:start).exactly(5).times
      expect(executor.unbootstrap).to be_a(Hash).and include(:error)
    end
  end


  describe '#deploy_server_with_tags', stubbed_knife: true do
    let(:current_tags) { @current_tags }
    let(:initial_tags) { %w(a b) }
    let(:joined_initial_tags) { initial_tags.join(' ') }
    let(:given_tags) { %w(c d) }
    let(:joined_given_tags) { given_tags.join(' ') }
    let(:deploy_server_with_tags) { executor.deploy_server_with_tags(given_tags, {}) }

    before do
      @current_tags = initial_tags.dup
      allow(stubbed_knife).to receive(:tags_list) { @current_tags }
      allow(stubbed_knife).to receive(:swap_tags) do |_, tags_to_delete, tags_to_add|
        @current_tags -= tags_to_delete.split
        @current_tags += tags_to_add.split
      end
      allow(executor).to receive(:deploy_server)
    end

    context 'when tags are empty' do
      it 'just deploys server' do
        expect(executor).to receive(:deploy_server)
        expect(stubbed_knife).not_to receive(:swap_tags)
        executor.deploy_server_with_tags([], {})
      end
    end

    context 'when tags are not empty' do
      it 'temporarily swaps current_tags with given ones, deploys server and then restores tags' do
        expect(stubbed_knife).to receive(:tags_list).ordered
        expect(stubbed_knife).to receive(:swap_tags).with(instance_of(String), joined_initial_tags, joined_given_tags).ordered
        expect(executor).to receive(:deploy_server).ordered
        expect(stubbed_knife).to receive(:swap_tags).with(instance_of(String), joined_given_tags, joined_initial_tags).ordered
        deploy_server_with_tags
      end
    end

    context 'if error occures during deploy' do
      it 'restores tags anyway' do
        allow(executor).to receive(:deploy_server) { raise }
        expect {
          deploy_server_with_tags
        }.to raise_error StandardError
        expect(current_tags).to eq initial_tags
      end
    end

    context 'if cannot add tags to server' do
      it 'returns :server_cannot_update_tags code' do
        allow(stubbed_knife).to receive(:swap_tags) { false }
        expect(deploy_server_with_tags).to eq 3
      end
    end
  end



  describe '#deploy_server', stubbed_knife: true do
    let(:deploy_info) { @deploy_info }
    let(:json_file_name) { 'json.json' }
    let(:json_file_path) { File.join(SpecSupport.tmp_dir, json_file_name) }

    let(:deploy_server) { executor.deploy_server(deploy_info) }

    before do
      allow(executor).to receive(:run_hook).with(:before_deploy, any_args)
      allow(executor).to receive(:run_hook).with(:after_deploy, any_args)
      allow(stubbed_knife).to receive(:ssh_stream) { 'Chef Client finished'}
      allow(stubbed_connector).to receive(:key) { double('Key', path: 'path_to_key') }
      allow(stubbed_connector).to receive(:server_update)
      @deploy_info = {}
    end


    it 'runs before_deploy and after_deploy hooks' do
      expect(executor).to receive(:run_hook).with(:before_deploy, any_args).ordered
      expect(executor).to receive(:run_hook).with(:after_deploy, any_args).ordered
      deploy_server
    end

    context 'when uses json file' do
      before(:all) do
        @tmp_files_at_start = Dir.entries(SpecSupport.tmp_dir)
      end
      before do
        allow(DevopsConfig).to receive(:config).and_return({
          project_info_dir: SpecSupport.tmp_dir,
          address: 'host.com',
          port: '8080',
          url_prefix: 'api'
        })
        deploy_info['use_json_file'] = true
      end

      after(:all) do
        diff = Dir.entries(SpecSupport.tmp_dir) - @tmp_files_at_start
        diff.each do |file|
          FileUtils.rm(File.join(SpecSupport.tmp_dir, file))
        end
      end


      it 'writes deploy_info to json file if it not exists' do
        expect { deploy_server }.to change { Dir.entries(SpecSupport.tmp_dir)}
      end

      it "writes deploy_info to given json file name if it doesn't exist" do
        FileUtils.rm(json_file_path) if File.exists?(json_file_path)
        deploy_info['json_file'] = json_file_name
        expect { deploy_server }.to change {
          Dir.entries(SpecSupport.tmp_dir)
        }
        FileUtils.rm(json_file_path)
      end

      it 'reads json from file if it exists' do
        deploy_info['json_file'] = json_file_name
        File.open(json_file_path, 'w') { |file| file.puts '{"foo": "bar"'}
        expect { deploy_server }.not_to change {
          Dir.entries(SpecSupport.tmp_dir)
        }
        FileUtils.rm(json_file_path)
      end

      it 'adds link to json to deploy command' do
        deploy_info['json_file'] = json_file_name
        regexp = %r(-j http://host.com:8080/api/v2.0/deploy/data/#{json_file_name})
        expect(stubbed_knife).to receive(:ssh_stream).with(anything, regexp, any_args)
        deploy_server
      end
    end

    context "doesn't use json file" do
      before do
        deploy_info['use_json_file'] = false
        deploy_info['run_list'] = %w(foo bar)
      end

      it "adds run list to command if server's stack is set" do
        server.stack = 'stack'
        expect(stubbed_knife).to receive(:ssh_stream).with(anything, %r(-r foo,bar), any_args)
        deploy_server
      end

      it "doesn't add run list to command if server's stack is unset" do
        expect(stubbed_knife).to receive(:ssh_stream).with(anything, 'chef-client --no-color', any_args)
        deploy_server
      end

      it "uses run list from named_task if it's set" do
        project.named_tasks = [{'name' => 'foo', 'run_list' => ['role[backend]', 'role[frontend]']}]
        deploy_info['named_task'] = 'foo'
        expect(stubbed_knife).to receive(:ssh_stream).with(anything, 'chef-client --no-color -o role[backend],role[frontend]', any_args)
        deploy_server
      end
    end

    it "uses server's key" do
      expect(stubbed_connector).to receive(:key).with('key_id')
      expect(stubbed_knife).to receive(:ssh_stream).with(any_args, 'path_to_key')
      deploy_server
    end

    it "uses public ip if it's set" do
      server.public_ip = '127.0.0.1'
      expect(stubbed_knife).to receive(:ssh_stream).with(anything, anything, '127.0.0.1', any_args)
      deploy_server
    end

    it "uses private_ip if public_ip isn't set" do
      expect(stubbed_knife).to receive(:ssh_stream).with(anything, anything, server.private_ip, any_args)
      deploy_server
    end

    context 'if deploy was successful' do
      it "updates server's last operation" do
        expect(server).to receive(:set_last_operation).with('deploy', anything)
        expect(stubbed_connector).to receive(:server_update).with(server)
        deploy_server
      end

      it 'returns 0' do
        expect(deploy_server).to eq 0
      end
    end

    context "when deploy wasn't successful" do
      before { allow(stubbed_knife).to receive(:ssh_stream) { 'fail'} }
      it "doesn't run after_deploy hook" do
        expect(executor).to receive(:run_hook).with(:before_deploy, any_args)
        expect(executor).not_to receive(:run_hook).with(:after_deploy, any_args)
        deploy_server
      end

      it 'returns 1' do
        expect(deploy_server).to eq 1
      end
    end
  end


  describe '#delete_from_chef_server', stubbed_knife: true do
    let(:delete_from_chef_server) { executor.delete_from_chef_server('foo') }
    before do
      allow(stubbed_knife).to receive(:chef_client_delete)
      allow(stubbed_knife).to receive(:chef_node_delete)
      delete_from_chef_server
    end

    it 'returns hash with :chef_node and :chef_client keys' do
      expect(delete_from_chef_server).to be_a(Hash).and include(:chef_node, :chef_client)
    end

    it 'calls to :chef_node_delete and :chef_client_delete' do
      expect(stubbed_knife).to have_received(:chef_client_delete)
      expect(stubbed_knife).to have_received(:chef_node_delete)
    end
  end


  describe '#delete_server' do
    let(:delete_server) { executor.delete_server }

    context 'when server is static' do
      before do
        server.provider = 'static'
        allow(stubbed_connector).to receive(:server_delete).with(server.id)
        allow(executor).to receive(:unbootstrap)
      end

      it 'performs unbootstrap' do
        expect(executor).to receive(:unbootstrap)
        delete_server
      end

      it 'deletes server from mongo' do
        expect(stubbed_connector).to receive(:server_delete).with(server.id)
        delete_server
      end

      it 'returns 0' do
        expect(delete_server).to eq 0
      end

      it "doesn't try to remove it from cloud" do
        expect{delete_server}.not_to raise_error
      end
    end

    context "when server isn't static", stubbed_knife: true do
      before do
        allow(server).to receive_message_chain('provider_instance.delete_server')
        allow(stubbed_connector).to receive(:server_delete).with(server.id)
        allow(stubbed_knife).to receive(:chef_node_delete)
        allow(stubbed_knife).to receive(:chef_client_delete)
      end

      it 'deletes from info about note chef server' do
        allow(executor).to receive(:delete_from_chef_server).and_call_original
        expect(executor).to receive(:delete_from_chef_server)
        delete_server
      end

      it "doesn't unbootstrap server" do
        expect(executor).not_to receive(:unbootstrap)
        delete_server
      end

      it 'deletes server from cloud' do
        expect(server).to receive_message_chain('provider_instance.delete_server').with(server)
        delete_server
      end

      it "doesn't raise error if server wasn't found in cloud" do
        allow(server).to receive_message_chain('provider_instance.name')
        allow(server).to receive_message_chain('provider_instance.delete_server') {
          raise Fog::Compute::OpenStack::NotFound
        }
        expect { delete_server }.not_to raise_error
      end

      it 'deletes server from mongo' do
        expect(stubbed_connector).to receive(:server_delete).with(server.id)
        delete_server
      end

      it 'returns 0' do
        expect(delete_server).to eq 0
      end
    end
  end


  describe '#rollback' do
    before do
      allow(executor).to receive(:delete_from_chef_server) { {} }
      allow(server).to receive_message_chain('provider_instance.delete_server')
    end

    it "does nothing if server.id is nil" do
      server.id = nil
      expect(executor).not_to receive(:delete_from_chef_server)
      expect(server).not_to receive(:provider_instance)
      executor.roll_back
    end

    it 'deletes node from chef server and instance from cloud' do
      expect(executor).to receive(:delete_from_chef_server)
      expect(server).to receive_message_chain('provider_instance.delete_server')
      executor.roll_back
    end

    it "doesn't raise if deleting server in cloud raises an error" do
      allow(server).to receive_message_chain('provider_instance.delete_server') { raise }
      expect { executor.roll_back }.not_to raise_error
    end
  end


  describe '#add_run_list_to_deploy_info' do
    it "doesn't change deploy info if it already includes run list" do
      deploy_info = {'run_list' => %w(foo)}
      expect {
        executor.add_run_list_to_deploy_info(output, deploy_info)
      }.not_to change { deploy_info }
    end

    it 'computes and adds run_list to deploy_info' do
      deploy_info = {}
      allow(executor).to receive(:compute_run_list) { %w(foo) }
      expect(executor).to receive(:compute_run_list)
      executor.add_run_list_to_deploy_info(output, deploy_info)
      expect(deploy_info['run_list']).to eq %w(foo)
    end
  end

  describe '#compute_run_list' do
    before do
      allow(deploy_env).to receive_message_chain('provider_instance.run_list') { %w(a) }
      project.run_list = %w(b)
      deploy_env.run_list = %w(c)
      server.run_list = %w(d)
    end

    it "returns array with run list merged from provider's, project's, env's and server's run lists" do
      expect(executor.compute_run_list).to be_an(Array).and contain_exactly(*%w(a b c d))
    end

    it "includes stack's run list if stack is set", stubbed_connector: true do
      server.stack = 'stack'
      allow(stubbed_connector).to receive(:stack) { instance_double(Devops::Model::StackEc2, run_list: %w(e)) }
      expect(executor.compute_run_list).to be_an(Array).and contain_exactly(*%w(a b c d e))
    end

    it "doesn't contain nils" do
      server.run_list = nil
      server.stack = 'stack'
      allow(stubbed_connector).to receive(:stack) { instance_double(Devops::Model::StackEc2, run_list: nil) }
      expect(executor.compute_run_list).to be_an(Array).and contain_exactly(*%w(a b c))
    end

    it 'returns uniq elements' do
      project.run_list = %w(a)
      deploy_env.run_list = %w(a)
      expect(executor.compute_run_list).to be_an(Array).and contain_exactly(*%w(a d))
    end
  end
end