Testing Rails helpers

application_helper_spec.rb

require 'ostruct'
require File.expand_path('../../../app/helpers/application_helper', __FILE__)

describe ApplicationHelper do
  let(:current_user) { OpenStruct.new(email: 'me@example.com', name: 'Foo Bar') }
  let(:view) { double('view') }
  subject { view }

  before do
    view.extend ApplicationHelper
    view.stub current_user: current_user
  end

  it 'does whatever an ApplicationHelper does' do
    # Stub as necessary
    # Insert expectations here
  end
end