SI-2712 Add support for higher order unification

1 files changed, 25 insertions, 0 deletions

diff --git a/test/files/pos/t2712-2.scala b/test/files/pos/t2712-2.scala
new file mode 100644
index 0000000000..39f22dd92a
--- /dev/null
+++ b/test/files/pos/t2712-2.scala
@@ -0,0 +1,25 @@
+package test
+
+// See: https://github.com/milessabin/si2712fix-demo/issues/3
+object Test {
+  trait A[T1, T2] { }
+  trait B[T1, T2] { }
+  class C[T] extends A[T, Long] with B[T, Double]
+  class CB extends A[Boolean, Long] with B[Boolean, Double]
+
+  trait A2[T]
+  trait B2[T]
+  class C2[T] extends A2[T] with B2[T]
+  class CB2 extends A2[Boolean] with B2[Boolean]
+
+  def meh[M[_], A](x: M[A]): M[A] = x
+
+  val m0 = meh(new C[Boolean])
+  m0: C[Boolean]
+  val m1 = meh(new CB)
+  m1: A[Boolean, Long]
+  val m2 = meh(new C2[Boolean])
+  m2: C2[Boolean]
+  val m3 = meh(new CB2)
+  m3: A2[Boolean]
+}