[ruby-core:110278] [Ruby master Bug#19047] DelegateClass displays "method redefined" warning when overriding methods

["jonathanhefner (Jonathan Hefner)" <noreply@ruby-lang.org>]

Issue #19047 has been updated by jonathanhefner (Jonathan Hefner).


> Thank you, now the issue is that `delegate` doesn't have a maintainer: https://github.com/ruby/ruby/commit/1159dbf305603b60a1e5d2b9ff77a9cf30775296

What is involved in being a maintainer?  Is that something I can volunteer for?


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Bug #19047: DelegateClass displays "method redefined" warning when overriding methods
https://bugs.ruby-lang.org/issues/19047#change-99565

* Author: jonathanhefner (Jonathan Hefner)
* Status: Open
* Priority: Normal
* ruby -v: ruby 3.1.2p20
* Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN
----------------------------------------
Perhaps this is not a bug, but it does seem unexpected.

When creating a `DelegateClass` class without an intervening ancestor, overriding a method displays "method redefined" warning:

```ruby
Base = Class.new do
  def foo
    "foo"
  end
end

Delegate1 = DelegateClass(Base) do
  def foo
    super + "1"
  end
end
# warning: method redefined; discarding old foo

Delegate2 = Class.new(DelegateClass(Base)) do
  def foo
    super + "2"
  end
end
# no warning

Delegate1.new(Base.new).foo
# => "foo1"

Delegate2.new(Base.new).foo
# => "foo2"
```

One possible solution would be to evaluate the `DelegateClass` block in a separate module, and prepend that module to the returned class.

Another possible solution would be to silence warnings around [when the block is evaluated](https://github.com/ruby/delegate/blob/df2283b8d8874446086b80355c586397f1b48d53/lib/delegate.rb#L442).

I would be happy to submit a PR to https://github.com/ruby/delegate if this is something we want to address.




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