Merge pull request #1615 from retronym/ticket/6648

SI-6648 copyAttrs must preserve TypeTree#wasEmpty

1 files changed, 24 insertions, 0 deletions

diff --git a/test/files/pos/t6648.scala b/test/files/pos/t6648.scala
new file mode 100644
index 0000000000..9593ebfee9
--- /dev/null
+++ b/test/files/pos/t6648.scala
@@ -0,0 +1,24 @@
+abstract class Node extends NodeSeq
+trait NodeSeq extends Seq[Node]
+object NodeSeq {
+  implicit def seqToNodeSeq(ns: Seq[Node]): NodeSeq = ???
+   def foo[B, That](f: Seq[B])(implicit bf: scala.collection.generic.CanBuildFrom[Seq[Int], B, That]): That = ???
+}
+
+class Transformer {
+  def apply(nodes: Any): Any = ???
+}
+
+object transformer1 extends Transformer {
+  // Adding explicit type arguments, or making the impilcit view
+  // seqToNodeSeq explicit avoids the crash
+  NodeSeq.foo {
+    // These both avoid the crash:
+    // val t = new Transformer {}; t.apply(null)
+    // new Transformer().apply(null)
+    new Transformer {}.apply(null)
+
+    null: NodeSeq
+  }: NodeSeq
+}
+