Exporting `this.xxx` in `this` compiles without warning

[EugeneFlesselle]

Compiler version

Scala compiler version 3.6.4-RC1-bin-SNAPSHOT-nonbootstrapped-git-bd07317 -- Copyright 2002-2024, LAMP/EPFL

Minimized example

trait P:
  def foo: Int

class A extends P:
  export this.foo

Output

No error or warning.
We generate the following cyclic definition:

class A() extends Object(), Test.P {
  export this.foo
  final def foo: Int = this.foo
}

Expectation

I would expect at least a warning here.

[mbovel]

This issue was picked for the Scala Issue Spree of tomorrow, Monday, February 3rd. @bracevac and @jan-pieter will be working on it.

[jan-pieter]

Some observations:

• When the trait P has an implementation for foo you correctly get an error that it is already a member.
• Support for exporting deferred members was added in this commit
• The Scala 3 reference only allows exporting when its owner is not a base class of the class containing the export clause