Rspec multiple runs because of exit when testing forked process

[SephVelut]

I'm having difficulties testing code that happens to fork processes.

# code under test
exit if fork
Process.setsid
exit if fork

Will cause rspec to run more than once because of the Kernel#exit. Using exit! changes this behavior. Any proposed rspec solutions I'm missing?

Related #1164 & #977

I have rspec installed with bundler. Running it via rspec command. Fresh install, no changed to spec_helper.

[myronmarston]

In RSpec 3, we avoid the at_exit hook unless it's absolutely necessary (e.g. due to the user trying to run things through ruby path/to/spec.rb instead the rspec command), so I would not expect a problem. What version of RSpec are you using? How are you running RSpec? Can you provide an executable example demonstrating the problem?

[SephVelut]

https://github.com/SephVelut/rspec_runs_again_on_exit

I setup a repo with an executable demonstration. The code is bare minimum and I have commented the areas of interest.

When attempting to create a daemon process on unix, a second fork is spawned to prevent the daemon from acquiring a controlling terminal. Rspec runs once for the parent of the daemon when the parent eventually returns. Rspec then runs again for the forked process when it exists. This might not even be a technical problem, but it is a gothcha when forking and exiting processes that originated from a spec.

I'm avoiding the issue right now by catching SystemExit and exiting from rspec quietly.

it 'spec' do
   begin
       r = Test.new.spawn
   rescue SystemExit
       exit!
    end
    expect(r).to eq(true)
end

This will output for the parent but ignore the child.

[myronmarston]

Addressed in #2058.

[SephVelut]

Don't you mean #2063?

[myronmarston]

Yes. Whoops!