SI-2712 Add support for higher order unification

1 files changed, 24 insertions, 0 deletions

diff --git a/test/files/pos/t2712-3.scala b/test/files/pos/t2712-3.scala
new file mode 100644
index 0000000000..46445f9289
--- /dev/null
+++ b/test/files/pos/t2712-3.scala
@@ -0,0 +1,24 @@
+package test
+
+object Test1 {
+  class Foo[T, F[_]]
+  def meh[M[_[_]], F[_]](x: M[F]): M[F] = x
+  meh(new Foo[Int, List]) // solves ?M = [X[_]]Foo[Int, X[_]] ?A = List ...
+}
+
+object Test2 {
+  trait TC[T]
+  class Foo[F[_], G[_]]
+  def meh[G[_[_]]](g: G[TC]) = ???
+  meh(new Foo[TC, TC]) // solves ?G = [X[_]]Foo[TC, X]
+}
+
+object Test3 {
+  trait TC[F[_]]
+  trait TC2[F[_]]
+  class Foo[F[_[_]], G[_[_]]]
+  new Foo[TC, TC2]
+
+  def meh[G[_[_[_]]]](g: G[TC2]) = ???
+  meh(new Foo[TC, TC2]) // solves ?G = [X[_[_]]]Foo[TC, X]
+}