[ruby-core:117628] [Ruby master Bug#20440] `super` from child class passing keyword arg as Hash if in a method with passthrough args called from base class

Issue #20440 has been updated by ozydingo (Andrew Schwartz).


Thanks both. I understand that Ruby 3 requires explicit handling of keyword arguments. What still seems off to me is that `super` is _modifying_ the arguments. The child method is being passed a keyword argument, and `super` is forwarding keywords arguments *and* a Hash positional argument. Should it not be the case that either the method defined with only `*` does not accept keyword arguments or that `super` preserves the form of the arguments that were passed?

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Bug #20440: `super` from child class passing keyword arg as Hash if in a method with passthrough args called from base class
https://bugs.ruby-lang.org/issues/20440#change-108036

* Author: ozydingo (Andrew Schwartz)
* Status: Closed
* ruby -v: 3.3.0
* Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN
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Apologies for the verbose title, but that's the specific set of conditions that AFAICT are required to reproduce the bug!

Here's the simplest setup I can reproduce:

```rb
class Base
  def foo(*args, x: 1)
    puts "Base: calling foo with args: #{args}, x: #{x}"
  end

  def foo!(x: 1)
    puts "Base: calling foo! with x: #{x}"
    foo(x: x)
  end
end

class Child < Base
  def foo(*)
    puts "Child: calling foo"
    super
  end
end
```

When I call `Child.new.foo!`, I expect it to call the base class method `foo!`, which will use the default keyword arg `x: 1`; then the child method `foo` with `x: 1`, and finally the base method `foo` with `x: 1`. However, this is not what I observe:

```rb
Child.new.foo!

Base: calling foo! with x: 1
Child: calling foo
Base: calling foo with args: [{:x=>1}], x: 1
```

So when the child `foo` method called `super`, it passed not only `x: 1` as a keyword arg, but *also* `{x: 1}` as a Hash positional arg to the super method.

This is breaking my upgrade to Ruby 3.0 as I have a similar setup but without the `*args` param, this I am getting the error "wrong number of arguments (given 1, expected 0)".



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