Refine pretypeArgs

It worked more or less by accident before. Now it's more complicated,
but we also have tests.

1 files changed, 17 insertions, 0 deletions

diff --git a/tests/neg/overloaded.scala b/tests/neg/overloaded.scala
new file mode 100644
index 000000000..ce971ebcf
--- /dev/null
+++ b/tests/neg/overloaded.scala
@@ -0,0 +1,17 @@
+// testing the limits of parameter type inference
+
+object Test {
+  def mapX(f: Char => Char): String = ???
+  def mapX[U](f: U => U): U = ???
+  mapX(x => x) // error: missing parameter type
+
+  def foo(f: Char => Char): Unit = ???
+  def foo(f: Int => Int): String = ???
+  foo(x => x) // error: missing parameter type
+
+  def bar(f: (Char, Char) => Unit): Unit = ???
+  def bar(f: Char => Unit) = ???
+  bar((x, y) => ())
+  bar (x => ())
+
+}