NullIO#closed? should return false

[MSP-Greg]

Description

Currently returns true.

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[MSP-Greg]

@eregon Sorry for the ping. The test mentioned above fails frequently on truffleruby. Every time I've seen the error, I check truffleruby-head, and it passes there. The test is here. If you have any ideas...

JFYI, Puma is testing on Windows mswin...

[eregon]

I have no specific idea, I think adding the skip is fine here if needed, although a check against RUBY_ENGINE_VERSION would be better since it seems already fixed on truffleruby-head (and so should be for the next release as well).

The sleep 0.1 in that test are probably very timing-sensitive though (and make the test slow), that should probably be avoided if possible.

[MSP-Greg]

a check against RUBY_ENGINE_VERSION

I'm a bit TruffleRuby challenged. Would RUBY_ENGINE_VERSION < '22.2' be okay? Or, something a bit more complicated?

The sleep 0.1 in that test are probably very timing-sensitive though (and make the test slow

Given how long a few other tests take, not concerned about time. Also, some of the timing is related to Actions (one VM on a four VM system). Or, many of the test delays aren't needed when I run locally...

[eregon]

omit/skip unless Gem::Version.new(RUBY_ENGINE_VERSION) > Gem::Version.new('22.1') seems more robust and is true for both 22.2.0-dev-8839057f and upcoming 22.2.

[MSP-Greg]

@eregon - Thanks, updated.