False positive in warning about param names in implementations

[beta-ziliani]

Take the following code:

abstract class Foo
  abstract def foo(x : Int32)
end

module FooM
  def foo(x : Int32); end
end

class Bar < Foo
  include FooM
  def foo(y : Int32 | String); end
end

In this code, FooM correctly matches Foo's abstract def, however with #11915 + #12167 it warns:

warning in line 11
Warning: positional parameter 'y' corresponds to parameter 'x' of the overridden method Foo#foo(x : Int32), ...

[beta-ziliani]

Similar:

module Foo
  abstract def foo(x : Int32)
end

class FooM
  def foo(x : Int32); end
end

class Bar < FooM
  include Foo

  def foo(y : Int32 | String); end
end

[HertzDevil]

#foo will be looked up in Bar before FooM even though FooM#foo is stricter than Bar#foo:

abstract class Foo
  abstract def foo(x : Int32)
end

module FooM
  def foo(x : Int32); 1; end
end

class Bar < Foo
  include FooM
  def foo(y : Int32 | String); 2; end
end

Bar.new.foo(0)  # => 2
Bar.new.foo("") # => 2

So I think this error is appropriate, because Foo#foo is ultimately implemented in Bar, not FooM.

[beta-ziliani]

Ah I see, thanks!