Ruby

It looks like when moving to 2.4 and higher, the access to protected method has changed. In the following case:

class Foo def bar(objects) objects.map(&:baz) end protected def baz self.inspect end end a = Foo.new; b = Foo.new a.bar([b]) 

The protected method '...' called will be raised. I haven't seen any explicit mention of this in the release notes.
It can be rewritten to successfully run as:

objects.map { |x| x.baz } 

But it was an unexpected change. (so potentially a bug?)