Harden implicit scope computation against CyclicReference errors.

1 files changed, 51 insertions, 0 deletions

diff --git a/tests/pos/SI-7638.scala b/tests/pos/SI-7638.scala
new file mode 100644
index 000000000..ed581efe9
--- /dev/null
+++ b/tests/pos/SI-7638.scala
@@ -0,0 +1,51 @@
+package miniboxing.tests.compile
+
+trait Ordering[@specialized(Int) A] {
+  def eqv(x: Array[A], y: Array[A]): Boolean = false
+}
+
+trait ArrayVectorOrder[@specialized(Int) A] extends Ordering[A] {
+  override def eqv(x: Array[A], y: Array[A]): Boolean = super.eqv(x, y)
+}
+
+object vectorOrder {
+  implicit def arrayOrder[@specialized(Int) A](): miniboxing.tests.compile.ArrayVectorOrder[A] =
+  /*
+   * Before applying patch:
+   *
+   *      while compiling: SI-7638.scala
+   *         during phase: mixin
+   *      library version: version 2.10.3-20130625-164027-d22e8d282c
+   *     compiler version: version 2.10.3-20130627-153946-54cb6af7db
+   *   reconstructed args:
+   *
+   *   last tree to typer: TypeTree(class Array)
+   *               symbol: class Array in package scala (flags: final)
+   *    symbol definition: final class Array[T >: ? <: ?] extends Object
+   *                  tpe: Array[Int]
+   *        symbol owners: class Array -> package scala
+   *       context owners: anonymous class anon$1 -> package compile
+   *
+   * == Expanded type of tree ==
+   *
+   * TypeRef(
+   *   TypeSymbol(final class Array[T >: ? <: ?] extends Object)
+   *   args = List(TypeRef(TypeSymbol(final abstract class Int extends )))
+   * )
+   *
+   * unhandled exception while transforming SI-7638.scala
+   * error: uncaught exception during compilation: java.lang.UnsupportedOperationException
+   * error: java.lang.UnsupportedOperationException: tail of empty list
+   * 	at scala.collection.immutable.Nil$.tail(List.scala:339)
+   * 	at scala.collection.immutable.Nil$.tail(List.scala:334)
+   * 	at scala.tools.nsc.transform.Mixin$$anonfun$scala$tools$nsc$transform$Mixin$$rebindSuper$1.apply(Mixin.scala:123)
+   * 	at scala.tools.nsc.transform.Mixin$$anonfun$scala$tools$nsc$transform$Mixin$$rebindSuper$1.apply(Mixin.scala:122)
+   * 	at scala.reflect.internal.SymbolTable.atPhase(SymbolTable.scala:207)
+   * 	at scala.reflect.internal.SymbolTable.afterPhase(SymbolTable.scala:216)
+   * 	at scala.tools.nsc.Global.afterPickler(Global.scala:1104)
+   * 	at scala.tools.nsc.transform.Mixin.scala$tools$nsc$transform$Mixin$$rebindSuper(Mixin.scala:122)
+   * 	at scala.tools.nsc.transform.Mixin$$anonfun$scala$tools$nsc$transform$Mixin$$mixinTraitMembers$1$1.apply(Mixin.scala:339)
+   * 	at scala.tools.nsc.transform.Mixin$$anonfun$scala$tools$nsc$transform$Mixin$$mixinTraitMembers$1$1.apply(Mixin.scala:292)
+   */
+    new ArrayVectorOrder[A] { }
+}