Array dereference from SimpleDelegator doesn't work in each (iterating)

[frvade]

Description

Array dereference in truffleruby works with arrays, but doesn't work with wrapped delegated arrays

How to reproduce

irb(main):001:0> Desc = Class.new(SimpleDelegator)
=> Desc
irb(main):002:0> obj = Desc.new([:first, :second])
=> [:first, :second]
irb(main):003:0> [obj].each { |first, second| p first, second }
[:first, :second]
nil
=> [[:first, :second]]
irb(main):004:0> [obj].each { |(first, second)| p first, second }
:first
:second
=> [[:first, :second]]
irb(main):005:0> first, second = obj
=> [:first, :second]
irb(main):006:0> p first, second
:first
:second
irb(main):007:0> RUBY_VERSION
=> "3.0.3"
irb(main):008:0> exit
user@lima-default:/Users/user/projects/github/gruf-demo$ ruby -v
truffleruby 22.2.0, like ruby 3.0.3, GraalVM CE Native [x86_64-linux]

In MRI it would be

irb(main):001:0> Desc = Class.new(SimpleDelegator)
=> Desc
irb(main):002:0> obj = Desc.new([:first, :second])
=> [:first, :second]
irb(main):003:0> [obj].each { |first, second| p first, second }
:first
:second
=> [[:first, :second]]
irb(main):004:0> [obj].each { |(first, second)| p first, second }
:first
:second
=> [[:first, :second]]
irb(main):005:0> first, second = obj
=> [:first, :second]
irb(main):006:0> p first, second
:first
:second
irb(main):007:0> RUBY_VERSION
=> "3.0.3"
irb(main):008:0> exit
user@lima-default:/Users/user/projects/github/gruf-demo$ ruby -v
ruby 3.0.3p157 (2021-11-24 revision 3fb7d2cadc) [x86_64-linux]

The normal array dereference works as expected as well as not wrapped array in each

[eregon]

Thanks for the report.

A minimal repro based on that is:

require 'delegate'

Desc = Class.new(SimpleDelegator)
obj = Desc.new([:first, :second])
[obj].each { |first, second| p first, second }

puts "regular array:"
[[:first, :second]].each { |first, second| p first, second }

ruby 3.0.3p157 (2021-11-24 revision 3fb7d2cadc) [x86_64-linux]
:first
:second
regular array:
:first
:second

truffleruby 22.3.0-dev-16c74eb6, like ruby 3.0.3, Interpreted JVM [x86_64-linux]
[:first, :second]
nil
regular array:
:first
:second

[eregon]

Fixed in c00d9f4