SI-6840 fixes weird typing of quasiquote arguments

Previously quasiquote arguments were type checked against Any
which caused weird inference that made splicing of complex expressions
unusable:

   val l1 = List(q"foo")
   val l2 = List(q"bar")
   q"f(..${l1 ++ l2})" // argument type checked as Any instead of List[Tree]

This is fixed by forcing compiler to type check against type
variable which itself isn't used in any other way.

1 files changed, 9 insertions, 0 deletions

diff --git a/test/files/scalacheck/quasiquotes/TermConstructionProps.scala b/test/files/scalacheck/quasiquotes/TermConstructionProps.scala
index 9284903623..f68656d0f7 100644
--- a/test/files/scalacheck/quasiquotes/TermConstructionProps.scala
+++ b/test/files/scalacheck/quasiquotes/TermConstructionProps.scala
@@ -199,4 +199,13 @@ object TermConstructionProps extends QuasiquoteProperties("term construction") {
     def withEvidence = q"def foo[T: X]"
     assert(!(withEvidence ≈ withEvidence))
   }
+
+  property("make sure inference doesn't infer any") = test {
+    val l1 = List(q"foo")
+    val l2 = List(q"bar")
+    val baz = q"baz"
+    assert(q"f(..${l1 ++ l2})" ≈ q"f(foo, bar)")
+    assert(q"f(..${l1 ++ l2}, $baz)" ≈ q"f(foo, bar, baz)")
+    assert(q"f(${if (true) q"a" else q"b"})" ≈ q"f(a)")
+  }
 }