I'm very confused as to what's going on here and where exactly the problem lies :S

Apparently, the root problem is this bug in HtmlUnit. As you know, Celerity is a wrapper for HtmlUnit and it comes with a bundled snapshot of the HtmlUnit jars, which means that in a recent update to Celerity, when the latest HtmlUnit was pulled in from upstream, the bug started to manifest itself.

I see it in my RSpec/Steak/Capybara/Culerity/Celerity workflow as spec runs which complete successfully (0 failures) but never actually fully exit because the JVM just sits hanging, waiting for something...

The workaround is to call @_browser.close explicitly in the at_exit handler. The Celerity author thinks that the right place to put the workaround is not actually in Celerity, but possibly in either Capybara or Culerity. I myself am not sure.

All I know is that if I change this in Capybara's Culerity driver from:

@_browser = ::Culerity::RemoteBrowserProxy.new self.class.server, {:browser => :firefox, :log_level => :off}
at_exit do
  @_browser.exit
end

To:

@_browser = ::Culerity::RemoteBrowserProxy.new self.class.server, {:browser => :firefox, :log_level => :off}
at_exit do
  @_browser.close
  @_browser.exit
end

Then the hanging goes away.

It seems a workaround of some kind needs to go in somewhere, because the HtmlUnit team seems pretty slow to respond on this issue (look at the date on that issue tracker ticket linked above, and the lack of response).

I don't know. Do you think this extra @_browser.close call should go in Capybara's Culerity driver? Or should it be happening somewhere inside Culerity itself?

Does this break when used with the current stable version of celerity? If it doesn't, then there's no harm in adding that extra call, imho.

Let me just check now...

Ok, just rolled back from Celerity 0.8.0.beta.1 to Celerity 0.7.9 and it seems that the extra @_browser.close doesn't do any harm. Let me know if you want me to push a patch for it; already got one here in my local fork. It's just that one line addition.

Pushed it here in case you want it:

http://github.com/wincent/capybara/commits/hanging-culerity-fix

This was pushed a long time ago, but I seem to have forgot to close this issue.