Several updated gems do not have releases yet:

* RubyGems 4.0.0.dev
* bundler 4.0.0.dev
* stringio 3.1.8.dev
* strscan 3.1.6.dev

And the usual CRuby-specific extension gems remain excluded.

This problem does not seem to be going away, so ignore all missing
extensions on JRuby for now.

See ruby/rubygems#3520

We removed the ability to automatically load extensions from jars
many years ago, but this test remained. It only continued to pass
because some other library loaded the 'json' library which meant
that the tested classes were available. When this same example is
run outside of the test suite, it fails:

```
$ cx jruby-10.0.2.0 ruby -e "require 'uri:file:./lib/ruby/stdlib/json/ext/parser'; p JSON::Ext::Parser"
NameError: uninitialized constant JSON::Ext::Parser
  const_missing at org/jruby/RubyModule.java:4866
         <main> at -e:1
```

Because this functionality no longer exists, I am removing the
test.

A few additional stdlib were added in 4.0 so this archive is now
a bit larger.

Testing all of these features together does not show useful
information when one of them is not pre-required, and basing the
spec name off the list of expected features means it cannot be
reliably tagged for exclusion.

The change here makes this a separate subprocess run for each
provided library, which improves the spec in a few different ways:

* Descriptions are meaningful and can be individually tagged.
  Previously, any change to the list of features would cause
  the spec description to change and error output did not clearly
  indicate which feature failed.
* Failed requires are represented with the string "error" so that
  failure output is useful. Previous logic would just report that
  the subprocess failed.
* Implementation-specific features do not have to be filtered out.
  Both CRuby and JRuby have features at boot that do not exist in
  other implementations, and may add others in the future. The spec
  should not need updating when that happens.

The require check and the loaded feature check are combined into a
single run for efficiency.

This spec was split into a separate spec for each feature to avoid
the description changing and to make the failures more useful.

* Removed SortedSet and related files (gem TBD).
* Removed stdlib .rb stub.
* Fixed inspect output, intersect? with Array, and infinite
  enumerables for new tests.
* Moved @hash variable to a bound Java field.

* Fix inspect output expectations.
* Guard SortedSet tests behind a require, since that collection is
  now in a separate library (knu/sorted_set). These tests probably
  should move to the external library once we work out the details
  (see knu/sorted_set#7)

Based on code from CRuby by Tomoya Ishida:

ruby/ruby#13680

When the incoming block's signature is important to the iteration
method being called, the previous logic would hide that signature.
The change here propagates it through the CallBlock.

This does not exactly match the new native Set impl, but it passes
specs and tests related to initialize.

See jruby#9265

See jruby#9266

See jruby#9267

See jruby#9268

JRuby does not detect deadlock beyond what JVM already does (only
when dumping thread statuses).

Does not parse currently.

See jruby#9269

See jruby#9270

See ruby/ruby#12914

We'll address these in jruby-openssl via fixes in
jruby/jruby-openssl#341 etc.

See jruby#9271

Test on MacOS

Not sure yet if there's a way to have separate open and connect
timeouts with JVM sockets.

Still not sure I get what "outer" is intended to mean but this
matches CRuby and now there's an equivalent function for
rb_exec_recursive.

This ensures appropriate encoding and path conversion errors are
raised.

See jruby#9275

See jruby#9276

Functionality is not yet hooked up.

This only implements it for a couple forms of read and for
Socket#connect. Other places still need to be wired up.