Proparage function result constrains when inferring parameter types

If an application has functions with implicit parameter types we need to be
more aggressive about propagating knowledge of the expected result type into
the constraint.

Fixes #1378.

1 files changed, 3 insertions, 0 deletions

diff --git a/tests/pos/i1378.scala b/tests/pos/i1378.scala
new file mode 100644
index 000000000..31475daf2
--- /dev/null
+++ b/tests/pos/i1378.scala
@@ -0,0 +1,3 @@
+object Test {
+  (1, x => 2): (Int, Int => Int)
+}