module Dotenv

def restore(env = @diff&.a, safe: Thread.current == Thread.main)

Parameters:
  • safe (Boolean) -- Is it safe to modify `ENV`? Defaults to `true` in the main thread, otherwise raises an error.
  • env (Hash) -- Hash of keys and values to restore, defaults to the last saved state 
def restore(env = @diff&.a, safe: Thread.current == Thread.main)
  # No previously saved or provided state to restore
  return unless env
  diff = Dotenv::Diff.new(b: env)
  return unless diff.any?
  unless safe
    raise ThreadError, <<~EOE.tr("\n", " ")
      Dotenv.restore is not thread safe. Use `Dotenv.modify { }` to update ENV for the duration
      of the block in a thread safe manner, or call `Dotenv.restore(safe: true)` to ignore
      this error.
    EOE
  end
  instrument(:restore, diff: diff) { ENV.replace(env) }
end