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Fuzzy type mismatch with macro: found: singleton type with base type A, required: A

I have

class Foo[A] {
  def foo[B](x: A, y: B) = y
}

class Bar[A] extends Foo[A] {
  override def foo[B](x: A, y: B) = superCall
}

where the superCallwhite box macro should expand to super.foo[B](x, y), and it shows -Ymacro-debug-lite. The problem is that it cannot compile with the following error:

[error] /home/aromanov/IdeaProjects/scala-dry/src/test/scala/com/github/alexeyr/scaladry/SuperTests.scala:80: type mismatch;
[error]  found   : y.type (with underlying type B)
[error]  required: B
[error]             override def foo[B](x: A, y: B) = superCall
[error]                                               ^

This makes no sense to me: y.typenarrower than B, therefore, if it is found when required B, this should not be a mistake. Even a stranger, if I replaced with the superCallextension super.foo[B](x, y), the error will disappear!

superCall(slightly simplified by removing irrelevant conditional expressions, you can see the full version on Github ):

def superCall: Tree = {
  val method = c.internal.enclosingOwner.asMethod
  val args = method.paramLists.map(_.map(sym => c.Expr(q"$sym")))
  val typeParams = method.typeParams.map(_.asType.name)
  q"super.${method.name.toTermName}[..$typeParams](...$args)"
}

EDIT: add -uniqidshows

[error]  found   : y#26847.type (with underlying type B#26833)
[error]  required: B#26834
[error]             override def foo[B](x: A, y: B) = superCall
[error]                                               ^
[error] one error found

, , , 2 B . B C, Foo.foo B, C , C.

2: . Scala typer , . typer (super.foo[B](x, y) superCall)

class Foo#26818[A#26819] extends scala#22.AnyRef#2757 {
  def <init>#26822(): Foo#26818[A#26819] = {
    Foo#26818.super.<init>#3104();
    ()
  };
  def foo#26823[B#26824](x#26827: A#26819, y#26828: B#26825): B#26824 = y#26828
};
class Bar#26820[A#26821] extends Foo#26818[A#26821] {
  def <init>#26831(): Bar#26820[A#26821] = {
    Bar#26820.super.<init>#26822();
    ()
  };
  override def foo#26832[B#26833](x#26836: A#26821, y#26837: B#26834): B#26833 = Bar#26820.super.foo#26823[B#26834](x#26836, y#26837)
};

, superCall Bar#26820.super.foo#26823[B#26833](x#26836, y#26837).

+4
1

, - - , - ? q"super.$methodName(...$args)", .

0

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