Testing Draper decorators with real helpers, including URL helpers.

example_spec.rb

require "spec_helper"

# :draper_with_helpers is necessary for the Draper objects
# to access real helpers, including URL helpers, in the spec.
describe MyDecorator, "#foo", :draper_with_helpers do

  # This is necessary for the spec itself to use URL helpers
  # like some_path().
  include Rails.application.routes.url_helpers

  let(:item) { Item.new }
  subject { MyDecorator.new(item).foo }

  it { should include some_path(item) }

end

spec_helper.rb

RSpec.configure do |config|
  config.treat_symbols_as_metadata_keys_with_true_values = true

  # Make helpers, including link helpers, work with Draper in specs.
  # https://github.com/jcasimir/draper/pull/49#issuecomment-4003191
  # NOTE: You may need to change ":all" to ":each" for this to work. See Gist comments.
  config.before(:all, :draper_with_helpers) do
    c = ApplicationController.new
    c.request = ActionDispatch::TestRequest.new
    c.set_current_view_context
  end
end

This is not working since this commit. This fork seems to do the trick.