Fix #9849: Add regression test

OlivierBlanvillain · OlivierBlanvillain · commit 224e8dc581ab · 2021-04-30T19:23:50.000+02:00
diff --git a/tests/pos/9849.scala b/tests/pos/9849.scala
@@ -0,0 +1,4 @@
+type *:[A, B] = A match
+  case (B *: x) => A
+  case (x *: y) => x *: (B *: y)
+  case _ => A *: B
