Strengthen requirement for auto-tupling

Was: corresponding parameter types "are compatible".
Now: corresponding parameter types "conform".

This avoids the inconsistency mentioned by @retronym in #897.

1 files changed, 4 insertions, 0 deletions

diff --git a/tests/neg/function-arity.scala b/tests/neg/function-arity.scala
index 86fbab49f..5e0cb1058 100644
--- a/tests/neg/function-arity.scala
+++ b/tests/neg/function-arity.scala
@@ -22,3 +22,7 @@ object Test {
   def foo(a: Any => String) = ()
   foo((a: Int, b: String) => a + b) // error: none of the overloaded alternatives of method foo match arguments (Int, Int)
 }
+object jasonComment {
+  implicit def i2s(i: Int): String = i.toString
+  ((x: String, y: String) => 42) : (((Int, Int)) => String) // error
+}