virtpatmat, hidden behind -Yvirtpatmat

at least one imminent TODO: undo hardwired generation of if/then/else,
and decide based on type whether to call flatMap/orElse or inline those
methods from Option

review by extempore

14 files changed, 105 insertions, 0 deletions

diff --git a/test/files/pos/virtpatmat_castbinder.flags b/test/files/pos/virtpatmat_castbinder.flags
new file mode 100644
index 0000000000..9769db9257
--- /dev/null
+++ b/test/files/pos/virtpatmat_castbinder.flags
@@ -0,0 +1 @@
+ -Yvirtpatmat -Xexperimental
diff --git a/test/files/pos/virtpatmat_castbinder.scala b/test/files/pos/virtpatmat_castbinder.scala
new file mode 100644
index 0000000000..be269638ce
--- /dev/null
+++ b/test/files/pos/virtpatmat_castbinder.scala
@@ -0,0 +1,15 @@
+class IntMap[+V]
+case class Bin[+T](m: IntMap[T]) extends IntMap[T]
+case class Tip[+T](x: T) extends IntMap[T]
+
+trait IntMapIterator[V, T] {
+  def valueOf(tip: Tip[V]): T
+  def pop: IntMap[V]
+
+  def next: T =
+    pop match {
+      case Bin(t@Tip(_)) => {
+        valueOf(t)
+      }
+    }
+}
\ No newline at end of file
diff --git a/test/files/pos/virtpatmat_exist1.flags b/test/files/pos/virtpatmat_exist1.flags
new file mode 100644
index 0000000000..9769db9257
--- /dev/null
+++ b/test/files/pos/virtpatmat_exist1.flags
@@ -0,0 +1 @@
+ -Yvirtpatmat -Xexperimental
diff --git a/test/files/pos/virtpatmat_exist1.scala b/test/files/pos/virtpatmat_exist1.scala
new file mode 100644
index 0000000000..6cad017b0b
--- /dev/null
+++ b/test/files/pos/virtpatmat_exist1.scala
@@ -0,0 +1,24 @@
+import annotation.unchecked.{ uncheckedVariance=> uV }
+import scala.collection.immutable.{ListMap, HashMap, ListSet, HashSet}
+
+object Test {
+  class HashMapCollision1[A, +B](var hash: Int, var kvs: ListMap[A, B @uV]) extends HashMap[A, B @uV]
+  class HashSetCollision1[A](var hash: Int, var ks: ListSet[A]) extends HashSet[A]
+
+  def splitArray[T](ad: Array[Iterable[T]]): Any =
+    ad(0) match {
+      case _: HashMapCollision1[_, _] | _: HashSetCollision1[_] => null
+    }
+
+    // without type ascription for the one in the body of the last flatmap of each alternative, type inference borks on the existentials
+    // def splitArray[T >: Nothing <: Any](ad: Array[Iterable[T]]): Any = { import OptionMatching._
+    //   runOrElse(ad.apply(0))(((x1: Iterable[T]) => (
+    //     or(((x4: Iterable[T]) => one(null)),
+    //       guard(x1.isInstanceOf[Iterable[T] with Test.HashMapCollision1[_,_]], x1.asInstanceOf[Iterable[T] with Test.HashMapCollision1[_,_]]).flatMap(((x2: Iterable[T] with Test.HashMapCollision1[_,_]) => one(x2))),
+    //       guard(x1.isInstanceOf[Test.HashSetCollision1[_]], x1.asInstanceOf[Iterable[T] with Test.HashSetCollision1[_]]).flatMap(((x3: Iterable[T] with Test.HashSetCollision1[_]) => one(x3)))): Option[Any]).orElse(
+    //     (zero: Option[Any])))
+    //   )
+    // }
+
+}
+
diff --git a/test/files/pos/virtpatmat_exist2.flags b/test/files/pos/virtpatmat_exist2.flags
new file mode 100644
index 0000000000..9769db9257
--- /dev/null
+++ b/test/files/pos/virtpatmat_exist2.flags
@@ -0,0 +1 @@
+ -Yvirtpatmat -Xexperimental
diff --git a/test/files/pos/virtpatmat_exist2.scala b/test/files/pos/virtpatmat_exist2.scala
new file mode 100644
index 0000000000..ee186074ab
--- /dev/null
+++ b/test/files/pos/virtpatmat_exist2.scala
@@ -0,0 +1,20 @@
+class ParseResult[+T]
+case class MemoEntry[+T](var r: Either[Nothing,ParseResult[_]])
+
+object Test {
+  def grow[T]: ParseResult[T] = (null: MemoEntry[T]) match {
+    case MemoEntry(Right(x: ParseResult[_])) => x.asInstanceOf[ParseResult[T]]
+  }
+
+  // what's the _$1 doing there?
+  // def grow[T >: Nothing <: Any]: ParseResult[T] = {
+  //   import OptionMatching._
+  //   runOrElse[MemoEntry[T], ParseResult[T]]((null: MemoEntry[T]))(((x1: MemoEntry[T]) =>
+  //     (MemoEntry.unapply[T](x1).flatMap[ParseResult[T]](((x4: Either[Nothing,ParseResult[_]]) =>
+  //       guard[Right[Nothing,ParseResult[_]]](x4.isInstanceOf[Right[Nothing,ParseResult[_]]], x4.asInstanceOf[Right[Nothing,ParseResult[_]]]).flatMap[ParseResult[T]](((cp3: Right[Nothing,ParseResult[_]]) =>
+  //         scala.Right.unapply[Nothing, ParseResult[_]](cp3).flatMap[ParseResult[T]](((x5: ParseResult[_]) =>
+  //           guard[ParseResult[_$1]](x5.ne(null), x5.asInstanceOf[ParseResult[_]]).flatMap[ParseResult[T]](((x6: ParseResult[_]) =>
+  //             one[ParseResult[T]](x6.asInstanceOf[ParseResult[T]]))))))))): Option[ParseResult[T]]
+  //     ).orElse[ParseResult[T]]((zero: Option[ParseResult[T]]))))
+  // }
+}
\ No newline at end of file
diff --git a/test/files/pos/virtpatmat_exist3.flags b/test/files/pos/virtpatmat_exist3.flags
new file mode 100644
index 0000000000..9769db9257
--- /dev/null
+++ b/test/files/pos/virtpatmat_exist3.flags
@@ -0,0 +1 @@
+ -Yvirtpatmat -Xexperimental
diff --git a/test/files/pos/virtpatmat_exist3.scala b/test/files/pos/virtpatmat_exist3.scala
new file mode 100644
index 0000000000..94385f32c9
--- /dev/null
+++ b/test/files/pos/virtpatmat_exist3.scala
@@ -0,0 +1,12 @@
+class ReferenceQueue[T] {
+  def wrapper(jref: ReferenceQueue[_]): ReferenceQueue[T] =
+    jref match {
+      case null => null
+    }
+
+  // def wrapper(jref: ReferenceQueue[_]): ReferenceQueue[T] = OptionMatching.runOrElse(jref)(((x1: ReferenceQueue[_]) =>
+  //   (OptionMatching.guard(null.==(x1), x1.asInstanceOf[ReferenceQueue[_]]).flatMap(((x2: ReferenceQueue[_]) =>
+  //     OptionMatching.one(null))): Option[ReferenceQueue[T]]).orElse(
+  //   (OptionMatching.zero: Option[ReferenceQueue[T]])))
+  // )
+}
\ No newline at end of file
diff --git a/test/files/pos/virtpatmat_gadt_array.flags b/test/files/pos/virtpatmat_gadt_array.flags
new file mode 100644
index 0000000000..9769db9257
--- /dev/null
+++ b/test/files/pos/virtpatmat_gadt_array.flags
@@ -0,0 +1 @@
+ -Yvirtpatmat -Xexperimental
diff --git a/test/files/pos/virtpatmat_gadt_array.scala b/test/files/pos/virtpatmat_gadt_array.scala
new file mode 100644
index 0000000000..f3332a897f
--- /dev/null
+++ b/test/files/pos/virtpatmat_gadt_array.scala
@@ -0,0 +1,15 @@
+import scala.collection.mutable._
+object Test {
+  def genericArrayOps[T](xs: Array[T]): ArrayOps[T] = xs match {
+    case x: Array[AnyRef]  => refArrayOps[AnyRef](x).asInstanceOf[ArrayOps[T]]
+    case null              => null
+  }
+  // def genericArrayOps[T >: Nothing <: Any](xs: Array[T]): scala.collection.mutable.ArrayOps[T]
+  //   = OptionMatching.runOrElse(xs)(((x1: Array[T]) =>
+  //     ((OptionMatching.guard(x1.isInstanceOf[Array[AnyRef]], x1.asInstanceOf[Array[T] with Array[AnyRef]]).flatMap(((x2: Array[T] with Array[AnyRef]) =>
+  //       OptionMatching.one(Test.this.refArrayOps[AnyRef](x2).asInstanceOf[scala.collection.mutable.ArrayOps[T]]))): Option[scala.collection.mutable.ArrayOps[T]]).orElse(
+  //     (OptionMatching.guard(null.==(x1), x1.asInstanceOf[Array[T]]).flatMap(((x3: Array[T]) =>
+  //         OptionMatching.one(null))): Option[scala.collection.mutable.ArrayOps[T]])): Option[scala.collection.mutable.ArrayOps[T]]).orElse((OptionMatching.zero: Option[scala.collection.mutable.ArrayOps[T]]))))
+
+  def refArrayOps[T <: AnyRef](xs: Array[T]): ArrayOps[T] = new ArrayOps.ofRef[T](xs)
+}
\ No newline at end of file
diff --git a/test/files/pos/virtpatmat_infer_single_1.flags b/test/files/pos/virtpatmat_infer_single_1.flags
new file mode 100644
index 0000000000..9769db9257
--- /dev/null
+++ b/test/files/pos/virtpatmat_infer_single_1.flags
@@ -0,0 +1 @@
+ -Yvirtpatmat -Xexperimental
diff --git a/test/files/pos/virtpatmat_infer_single_1.scala b/test/files/pos/virtpatmat_infer_single_1.scala
new file mode 100644
index 0000000000..b42af956cc
--- /dev/null
+++ b/test/files/pos/virtpatmat_infer_single_1.scala
@@ -0,0 +1,7 @@
+case class TypeBounds(a: Type, b: Type)
+class Type {
+  def bounds: TypeBounds = bounds match {
+    case TypeBounds(_: this.type, _: this.type) => TypeBounds(this, this)
+    case oftp                                   => oftp
+  }
+}
\ No newline at end of file
diff --git a/test/files/pos/virtpatmat_obj_in_case.flags b/test/files/pos/virtpatmat_obj_in_case.flags
new file mode 100644
index 0000000000..9769db9257
--- /dev/null
+++ b/test/files/pos/virtpatmat_obj_in_case.flags
@@ -0,0 +1 @@
+ -Yvirtpatmat -Xexperimental
diff --git a/test/files/pos/virtpatmat_obj_in_case.scala b/test/files/pos/virtpatmat_obj_in_case.scala
new file mode 100644
index 0000000000..496de4c12e
--- /dev/null
+++ b/test/files/pos/virtpatmat_obj_in_case.scala
@@ -0,0 +1,5 @@
+class ObjInCase {
+  0 match {
+    case _ => object o
+  }
+}
\ No newline at end of file