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SI-6663: don't ignore type parameter on selectDynamic invocation

Fix mkInvoke to handle selectDynamic calls of the form

  new C.foo[T].xyz

or

  new C.foo[T].xyz :U

(where C extends Dynamic)

Without this patch, the type parameter was silently ignored, and
possibly inferred to a different.

This patch fixes mkInvoke to handle these cases, where ctxTree has
the form Select(TypeApply(fun, targs), nme) or Typed(...)
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1 parent 8501088 commit c6569209dab006e74ccecc0ede6ce7815ac8629c @jannic jannic committed Nov 13, 2012
@@ -3935,9 +3935,14 @@ trait Typers extends Modes with Adaptations with Tags {
case t: ValOrDefDef => t.rhs
case t => t
}
- val (outer, explicitTargs) = cxTree1 match {
+ val cxTree2 = cxTree1 match {
+ case Typed(t, tpe) => t // ignore outer type annotation
+ case t => t
+ }
+ val (outer, explicitTargs) = cxTree2 match {
case TypeApply(fun, targs) => (fun, targs)
case Apply(TypeApply(fun, targs), args) => (Apply(fun, args), targs)
+ case Select(TypeApply(fun, targs), nme) => (Select(fun, nme), targs)
case t => (t, Nil)
}
def hasNamedArg(as: List[Tree]) = as.collectFirst{case AssignOrNamedArg(lhs, rhs) =>}.nonEmpty
@@ -0,0 +1,6 @@
+t6663.scala:16: error: type mismatch;
+ found : String
+ required: Int
+ var v = new C(42).foo[String].get :Int
+ ^
+one error found
View
@@ -0,0 +1,19 @@
+import language.dynamics
+
+class C(v: Any) extends Dynamic {
+ def selectDynamic[T](n: String): Option[T] = Option(v.asInstanceOf[T])
+ def applyDynamic[T](n: String)(): Option[T] = Option(v.asInstanceOf[T])
+}
+
+object Test extends App {
+ // this should be converted to
+ // C(42).selectDynamic[String]("foo").get
+ // causing a compile error.
+
+ // but, before fixing SI-6663, became
+ // C(42).selectDynamic("foo").get, ignoring
+ // the [String] type parameter
+ var v = new C(42).foo[String].get :Int
+ println(v)
+}
+
@@ -0,0 +1 @@
+42
View
@@ -0,0 +1,17 @@
+import language.dynamics
+
+class C(v: Any) extends Dynamic {
+ def selectDynamic[T](n: String): Option[T] = Option(v.asInstanceOf[T])
+ def applyDynamic[T](n: String)(): Option[T] = Option(v.asInstanceOf[T])
+}
+
+object Test extends App {
+ // this should be converted to
+ // C(42).selectDynamic[Int]("foo").get
+ // but, before fixing SI-6663, became
+ // C(42).selectDynamic[Nothing]("foo").get
+ // leading to a ClassCastException
+ var v = new C(42).foo[Int].get
+ println(v)
+}
+

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