CI against JRuby 9.1.9.0

[koic]

JRuby 9.1.9.0 has been released.

http://jruby.org/2017/05/16/jruby-9-1-9-0

[yahonda]

(Pointed to the wrong number. 1279 is the correct one)

CI for jruby-9.1.9.0 and ruby-head is failing due to #1279.

There is a similar error generated at simplecov .
https://travis-ci.org/colszowka/simplecov/jobs/232794265

[yahonda]

Opened simplecov-ruby/simplecov#582 to run CI against Ruby 9.1.0.0 to see if it reproduces with simplecov itself.

[koic]

Thanks for your advice.
It seems like a bug in JRuby 9.1.9.0. I will open an issue of JRuby later.

[koic]

I think that this build error will fix with the following PR.

simplecov-ruby/simplecov-html#53

I'd like to see how it goes for a while. How about this?

[yahonda]

Thanks for the investigation.
I'd like to see how jruby/jruby#4610 goes. Since this behavior change looks a regression for me which would affect many other users.

[koic]

Sure. I got it.

[koic]

It was a regression of JRuby 9.1.9.0. This regression issue was included in the milestone of JRuby 9.2.0.0.

https://github.com/jruby/jruby/milestone/53

If they have another regressions it is even better to test with them (That's fail fast) . So I think that it is good to merge this PR. Tell me what you think.

[yahonda]

Really great job. Thank you.

[koic]

Thanks too.