Using render_views
You can tell a controller example group to render views with the
  render_views declaration in any individual group, or globally.
Use render_views directly in a single group
Given a file named “spec/controllers/widgetscontrollerspec.rb” with:
require "rails_helper"
RSpec.describe WidgetsController, type: :controller do
  render_views
  describe "GET index" do
    it "has a widgets related heading" do
      get :index
      expect(response.body).to match /<h1>.*widgets/im
    end
  end
end
When I run rspec spec
Then the examples should all pass.
Use render_views on and off in nested groups
Given a file named “spec/controllers/widgetscontrollerspec.rb” with:
require "rails_helper"
RSpec.describe WidgetsController, type: :controller do
  context "with render_views" do
    render_views
    describe "GET index" do
      it "renders the actual template" do
        get :index
        expect(response.body).to match /<h1>.*widgets/im
      end
    end
    context "with render_views(false) nested in a group with render_views" do
      render_views false
      describe "GET index" do
        it "renders the RSpec generated template" do
          get :index
          expect(response.body).to eq("")
        end
      end
    end
  end
  context "without render_views" do
    describe "GET index" do
      it "renders the RSpec generated template" do
        get :index
        expect(response.body).to eq("")
      end
    end
  end
  context "with render_views again" do
    render_views
    describe "GET index" do
      it "renders the actual template" do
        get :index
        expect(response.body).to match /<h1>.*widgets/im
      end
    end
  end
end
When I run rspec spec --order defined --format documentation
Then the output should contain:
WidgetsController
  with render_views
    GET index
      renders the actual template
    with render_views(false) nested in a group with render_views
      GET index
        renders the RSpec generated template
  without render_views
    GET index
      renders the RSpec generated template
  with render_views again
    GET index
      renders the actual template
Use render_views globally
Given a file named “spec/support/render_views.rb” with:
RSpec.configure do |config|
  config.render_views
end
And a file named “spec/controllers/widgetscontrollerspec.rb” with:
require "rails_helper"
require "support/render_views"
RSpec.describe WidgetsController, type: :controller do
  describe "GET index" do
    it "renders the index template" do
      get :index
      expect(response.body).to match /<h1>.*widgets/im
    end
  end
end
When I run rspec spec
Then the examples should all pass.