test_temp_file_helper Gem

The TestTempFileHelper::TempFileHelper class manages the creation and cleanup of temporary files in automated tests.

Downloads and API docs are available on the test_temp_file_helper RubyGems page. API documentation is written using YARD markup.

Contributed by the 18F team, part of the United States General Services Administration: https://18f.gsa.gov/

Motivation

Rather than reimplement Pyfakefs in Ruby, in the short-term, I wrote this class to emulate Google's TEST_DATADIR and TEST_TMPDIR convention instead, so that I could test code that works with the file system.

Installation

Add this line to your application's Gemfile:

gem 'test_temp_file_helper'

And then execute:

$ bundle

Or install it yourself as:

$ gem install test_temp_file_helper

Usage

First, add the following to your Rakefile:

require 'test_temp_file_helper/rake'

TestTempFileHelper::SetupTestEnvironmentTask.new do |t|
  t.base_dir = File.dirname __FILE__
  t.data_dir = File.join('test', 'data')
  t.tmp_dir = File.join('test', 'tmp')
end

The SetupTestEnvironmentTask properties:

• base_dir: parent directory used to set the environment variables
• data_dir: directory relative to base_dir used to set TEST_DATADIR
• tmp_dir: directory relative to base_dir used to set TEST_TMPDIR

If an environment variable is already set, or if the corresponding property is not set on the SetupTestEnvironmentTask object, the environment variable will not be set or updated.

Then, create a TempFileHelper in your test's setup method, and call TempFileHelper.teardown in your test's teardown method.

require 'minitest/autorun'
require 'test_temp_file_helper'

class MyTest < ::Minitest::Test
  def setup
    @temp_file_helper = TestTempFileHelper::TempFileHelper.new
  end

  def teardown
    @temp_file_helper.teardown
  end

  def test_something_that_handles_files
    dir_path = @temp_file_helper.mkdir(File.join('path', 'to', 'dir'))
    file_path = @temp_file_helper.mkfile(File.join('path', 'to', 'file'))
    ...
  end
end

Contributing

1. Fork the repo ( https://github.com/18F/test_temp_file_helper/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Feel free to ping @mbland with any questions you may have, especially if the current documentation should've addressed your needs, but didn't.

Public domain

This project is in the worldwide public domain. As stated in CONTRIBUTING:

This project is in the public domain within the United States, and copyright and related rights in the work worldwide are waived through the CC0 1.0 Universal public domain dedication.

All contributions to this project will be released under the CC0 dedication. By submitting a pull request, you are agreeing to comply with this waiver of copyright interest.