WithEnv is an extremely small helper module for executing code with ENV variables. It exists because I got tired of re-writing or copying over a #with_env helper method for the 131st time.


Add this line to your application's Gemfile:

gem 'with_env'

And then execute:

$ bundle

Or install it yourself as:

$ gem install with_env


include WithEnv

with_env("FOO" => "BAR") do
  `echo $FOO` # => "BAR\n"
  ENV["FOO"] # => "BAR"

# The ENV has been restored to what it was before the
# above with_env block, so FOO no longer exists
`echo $FOO` # => "\n"
ENV.has_key?("FOO") # => false


After checking out the repo, run bin/setup to install dependencies. Then, run rake rspec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.


Bug reports and pull requests are welcome on GitHub at https://github.com/mhs/with_env-rb.


The gem is available as open source under the terms of the MIT License.