#delete compatibility with from SortedSet from Stdlib

[themilkman]

Hi,

I run in the following issue using SortedSet as drop in replacement:

3.0.2 :001 > str = "foo";ss = SortedSet.new; ss << str; hsh = { enabled: ss}; hsh[:enabled].delete(nil)
/home/me/.rvm/gems/ruby-3.0.2/gems/set-1.0.2/lib/set.rb:540:in `delete': comparison of NilClass with String failed (ArgumentError)
  from /home/me/.rvm/gems/ruby-3.0.2/gems/set-1.0.2/lib/set.rb:540:in `delete'
  from (irb):1:in `<main>'
  from /home/me/.rvm/rubies/ruby-3.0.2/lib/ruby/gems/3.0.0/gems/irb-1.3.5/exe/irb:11:in `<top (required)>'
  from /home/me/.rvm/rubies/ruby-3.0.2/bin/irb:23:in `load'
  from /home/me/.rvm/rubies/ruby-3.0.2/bin/irb:23:in `<main>'

While with ruby 2.7.4:

2.7.4 :001 > str = "foo";ss = SortedSet.new; ss << str; hsh = { enabled: ss}; hsh[:enabled].delete(nil)
 => #<SortedSet: {"foo"}> 

If I debugged it correctly this is due to RBTree:

3.0.2 :002 >  rb = RBTree["", ""]; rb.delete(0)
(irb):4:in `delete': comparison of Integer with String failed (ArgumentError)
  from (irb):4:in `<main>'
  from /home/me/.rvm/rubies/ruby-3.0.2/lib/ruby/gems/3.0.0/gems/irb-1.3.5/exe/irb:11:in `<top (required)>'
  from /home/me/.rvm/rubies/ruby-3.0.2/bin/irb:23:in `load'
  from /home/me/.rvm/rubies/ruby-3.0.2/bin/irb:23:in `<main>'

Is this mismatch in functionality generally accepted or is it smth that should get solved in sorted_set?

Thanks and cheers!

[jaynetics]

IMHO this error should not leak from a dependency and SortedSet should be usable as a drop-in for Set (Liskov substitution)