scinote-web/spec/support/shared_contexts/rake.rb

require 'rake'

shared_context 'rake' do
  let(:rake)      { Rake::Application.new }
  let(:task_name) { self.class.top_level_description }
  let(:task_path) { "lib/tasks/#{task_name.split(':').first}" }
  subject         { rake[task_name] }

  def loaded_files_excluding_current_rake_file
    $".reject { |file| file == Rails.root.join("#{task_path}.rake").to_s }
  end

  before do
    Rake.application = rake
    Rake.application.rake_require(task_path,
                                  [Rails.root.to_s],
                                  loaded_files_excluding_current_rake_file)

    Rake::Task.define_task(:environment)
  end
end