FilesystemCleaner

group :test do
  gem 'filesystem_cleaner'
end

# spec/spec_helper.rb

RSpec.configure do |config|
 fs_cleaner = FileSystemCleaner.new(
   Rails.root.join("public", "system", "test", "files"),
   Rails.root.join("tmp, "files.bak")
 )

 config.before(:each) { fs_cleaner.save_files!(example) }
 config.after(:each)  { fs_cleaner.restore_files!(example) }
end

# spec/some_spec.rb

describe "a filesystem modification", file: true do  # `file: true` activates the cleaner
  before do
    test_file    = Rails.root.join("public", "system", "test", "files", "#{filename}.txt")
    `cp #{fixture_file} #{test_file}`
  end

  it "reads the file" do
    expect(MyFileReader.new(filename).to_s).to eq(File.read(fixture_file))
  end

  let(:filename)     { SecureRandom.uuid }
  let(:fixture_file) { Rails.root.join("spec", "fixtures", "some_data.txt") }
end

describe "applying a signature", file: true do

  before do
    `cp #{Settings.fixture_drawing} #{working_file}`
    post "/documents/#{document.id}/sign"
  end

  it "applies the engineer's signature" do
     # `quality_assurance_dir` is _not_ cleaned by filesystem_cleaner
    `cp #{working_file} #{Settings.quality_assurance_dir}`

    fname = filename
    RSpec.configure do |config|
      config.after(:suite) do
        qa_file_path = "#{Settings.quality_assurance_dir}/#{fname}"
        message      = "ssh me@my-host cat #{qa_file_path} | display - "
        puts
        puts
        print message
      end
    end
  end

end