// Tests variance checking on default methods import reflect.ClassTag class Foo[+A: ClassTag](x: A) { private[this] val elems: Array[A] = Array(x) def f[B](x: Array[B] = elems): Array[B] = x // error (1) should give a variance error here or ... } object Test extends App { val foo: Foo[Object] = new Foo[String]("A") val arr = foo.f[Object]() arr(0) = new Integer(1) // (1) ... will give an ArrayStoreException here } class Outer[+A](x: A) { private[this] var elem: A = x def getElem: A = elem class Inner(constrParam: A) { // error (2) should give a variance error here or ... elem = constrParam } } object Test2 extends App { val o1: Outer[String] = new Outer[String]("A") val o2: Outer[Object] = o1 new o2.Inner(new Integer(1)) val x: String = o1.getElem // (2) ... will give a classcast exeption here } trait HasY { type Y } // These are neg-tests corresponding to the pos-test Variances.scala // where all the variance annotations have been inverted. trait Foo1[+X] { def bar[Y <: X](y: Y) = y } // error trait Foo2[+X] { def bar(x: HasY { type Y <: X })(y: x.Y) = y } // error trait Foo3[-X] { def bar[Y >: X](y: Y) = y } // error trait Foo4[-X] { def bar(x: HasY { type Y >: X })(y: x.Y) = y } // error // These are neg-tests corresponding to the pos-test Variances.scala // where all the bounds have been flipped. trait Foo5[-X] { def bar[Y >: X](y: Y) = y } // error trait Foo6[-X] { def bar(x: HasY { type Y >: X })(y: x.Y) = y } // error trait Foo7[+X] { def bar[Y <: X](y: Y) = y } // error trait Foo8[+X] { def bar(x: HasY { type Y <: X })(y: x.Y) = y } // error