Merge pull request #3480 from paulp/pr/publicize-abstract-star

 Make the Abstract* classes public.

src/library/scala/collection/Iterable.scala

@@ -51,4 +51,4 @@ object Iterable extends TraversableFactory[Iterable] {
 }
 
 /** Explicit instantiation of the `Iterable` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractIterable[+A] extends AbstractTraversable[A] with Iterable[A]
+abstract class AbstractIterable[+A] extends AbstractTraversable[A] with Iterable[A]

src/library/scala/collection/Iterator.scala

@@ -1171,4 +1171,4 @@ trait Iterator[+A] extends TraversableOnce[A] {
 }
 
 /** Explicit instantiation of the `Iterator` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractIterator[+A] extends Iterator[A]
+abstract class AbstractIterator[+A] extends Iterator[A]

src/library/scala/collection/Map.scala

@@ -56,4 +56,4 @@ object Map extends MapFactory[Map] {
 }
 
 /** Explicit instantiation of the `Map` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractMap[A, +B] extends AbstractIterable[(A, B)] with Map[A, B]
+abstract class AbstractMap[A, +B] extends AbstractIterable[(A, B)] with Map[A, B]

src/library/scala/collection/Seq.scala

@@ -38,4 +38,4 @@ object Seq extends SeqFactory[Seq] {
 }
 
 /** Explicit instantiation of the `Seq` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractSeq[+A] extends AbstractIterable[A] with Seq[A]
+abstract class AbstractSeq[+A] extends AbstractIterable[A] with Seq[A]

src/library/scala/collection/Set.scala

@@ -44,4 +44,4 @@ object Set extends SetFactory[Set] {
 }
 
 /** Explicit instantiation of the `Set` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractSet[A] extends AbstractIterable[A] with Set[A]
+abstract class AbstractSet[A] extends AbstractIterable[A] with Set[A]

src/library/scala/collection/Traversable.scala

@@ -101,4 +101,4 @@ object Traversable extends TraversableFactory[Traversable] { self =>
 }
 
 /** Explicit instantiation of the `Traversable` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractTraversable[+A] extends Traversable[A]
+abstract class AbstractTraversable[+A] extends Traversable[A]

src/library/scala/collection/immutable/Map.scala

@@ -32,9 +32,9 @@ trait Map[A, +B] extends Iterable[(A, B)]
                     with MapLike[A, B, Map[A, B]] { self =>
 
   override def empty: Map[A, B] = Map.empty
-  
+
   /** Returns this $coll as an immutable map.
-   *  
+   *
    *  A new map will not be built; lazy collections will stay lazy.
    */
   @deprecatedOverriding("Immutable maps should do nothing on toMap except return themselves cast as a map.",  "2.11.0")
@@ -191,4 +191,4 @@ object Map extends ImmutableMapFactory[Map] {
 }
 
 /** Explicit instantiation of the `Map` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractMap[A, +B] extends scala.collection.AbstractMap[A, B] with Map[A, B]
+abstract class AbstractMap[A, +B] extends scala.collection.AbstractMap[A, B] with Map[A, B]

src/library/scala/collection/mutable/Buffer.scala

@@ -46,4 +46,4 @@ object Buffer extends SeqFactory[Buffer] {
 }
 
 /** Explicit instantiation of the `Buffer` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractBuffer[A] extends AbstractSeq[A] with Buffer[A]
+abstract class AbstractBuffer[A] extends AbstractSeq[A] with Buffer[A]

src/library/scala/collection/mutable/Iterable.scala

@@ -38,4 +38,4 @@ object Iterable extends TraversableFactory[Iterable] {
 }
 
 /** Explicit instantiation of the `Iterable` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractIterable[A] extends scala.collection.AbstractIterable[A] with Iterable[A]
+abstract class AbstractIterable[A] extends scala.collection.AbstractIterable[A] with Iterable[A]

src/library/scala/collection/mutable/Map.scala

@@ -89,4 +89,4 @@ object Map extends MutableMapFactory[Map] {
 }
 
 /** Explicit instantiation of the `Map` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractMap[A, B] extends scala.collection.AbstractMap[A, B] with Map[A, B]
+abstract class AbstractMap[A, B] extends scala.collection.AbstractMap[A, B] with Map[A, B]

src/library/scala/collection/mutable/Seq.scala

@@ -45,4 +45,4 @@ object Seq extends SeqFactory[Seq] {
 }
 
 /** Explicit instantiation of the `Seq` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractSeq[A] extends scala.collection.AbstractSeq[A] with Seq[A]
+abstract class AbstractSeq[A] extends scala.collection.AbstractSeq[A] with Seq[A]

src/library/scala/collection/mutable/Set.scala

@@ -43,4 +43,4 @@ object Set extends MutableSetFactory[Set] {
 }
 
 /** Explicit instantiation of the `Set` trait to reduce class file size in subclasses. */
-private[scala] abstract class AbstractSet[A] extends AbstractIterable[A] with Set[A]
+abstract class AbstractSet[A] extends AbstractIterable[A] with Set[A]

test/files/pos/t6948.scala

@@ -0,0 +1,10 @@
+object t6948 {
+  val rand = new scala.util.Random()
+  def a1 = rand.shuffle(0 to 5)
+  // Tis not to be
+  // def a2 = rand.shuffle(0 until 5)
+  def a3 = rand.shuffle(Vector(1, 2, 3))
+  def a4 = rand.shuffle(scala.collection.Seq(1, 2, 3))
+  def a5 = rand.shuffle(scala.collection.immutable.Seq(1, 2, 3))
+  def a6 = rand.shuffle(scala.collection.mutable.Seq(1, 2, 3))
+}

test/files/run/inferred-type-constructors.check

@@ -0,0 +1,56 @@
+warning: there were 2 feature warning(s); re-run with -feature for details
+                p.Iterable[Int]
+                p.Set[Int]
+                p.Seq[Int]
+                p.m.Set[Int]
+                p.m.Seq[Int]
+     private[m] p.m.ASet[Int]
+                p.i.Seq[Int]
+     private[i] p.i.ASet[Int]
+     private[i] p.i.ASeq[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Set[Int]
+                p.Iterable[Int]
+                p.Set[Int]
+                p.Iterable[Int]
+                p.Set[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Seq[Int]
+                p.Iterable[Int]
+                p.Seq[Int]
+                p.Iterable[Int]
+                p.Seq[Int]
+                p.Iterable[Int]
+                p.m.Set[Int]
+                p.Iterable[Int]
+                p.Set[Int]
+                p.Iterable[Int]
+                p.Iterable[Int]
+                p.Seq[Int]
+                p.Iterable[Int]
+                p.Seq[Int]
+                p.Iterable[Int]
+     private[p] p.ASet[Int]
+     private[p] p.AIterable[Int]
+                p.Iterable[Int]
+                p.i.Seq[Int]
+     private[p] p.AIterable[Int]
+                List[Nothing]
+                scala.collection.immutable.Vector[Nothing]
+                scala.collection.immutable.Iterable[(Int, Int)]
+                scala.collection.immutable.Set[Int]
+                Seq[Int]
+                Array[Int]
+                scala.collection.AbstractSet[Int]
+                Comparable[java.lang.String]
+                scala.collection.immutable.LinearSeq[Int]
+                Iterable[Int]

test/files/run/inferred-type-constructors.scala

@@ -0,0 +1,125 @@
+package p {
+  trait TCon[+CC[X]] {
+    def fPublic: CC[Int]                        = ???
+    private[p] def fPackagePrivate: CC[Int]     = ???
+    protected[p] def fPackageProtected: CC[Int] = ???
+  }
+  trait Iterable[+A] extends TCon[Iterable]
+  trait Set[A] extends Iterable[A] with TCon[Set]
+  trait Seq[+A] extends Iterable[A] with TCon[Seq]
+
+  private[p] abstract class AIterable[+A] extends Iterable[A]
+  private[p] abstract class ASeq[+A] extends AIterable[A] with Seq[A]
+  private[p] abstract class ASet[A] extends AIterable[A] with Set[A]
+
+  package m {
+    private[m] abstract class ASeq[A] extends p.ASeq[A] with Seq[A]
+    private[m] abstract class ASet[A] extends p.ASet[A] with Set[A]
+    trait Set[A] extends p.Set[A] with TCon[Set]
+    trait Seq[A] extends p.Seq[A] with TCon[Seq]
+    trait BitSet extends ASet[Int]
+    trait IntSeq extends ASeq[Int]
+  }
+
+  package i {
+    private[i] abstract class ASeq[+A] extends p.ASeq[A] with Seq[A]
+    private[i] abstract class ASet[A] extends p.ASet[A] with Set[A]
+    trait Set[A] extends p.Set[A] with TCon[Set]
+    trait Seq[+A] extends p.Seq[A] with TCon[Seq]
+    trait BitSet extends ASet[Int]
+    trait IntSeq extends ASeq[Int]
+  }
+}
+
+object Test {
+  import scala.reflect.runtime.universe._
+  // Complicated by the absence of usable type constructor type tags.
+  def extract[A, CC[X]](xs: CC[A]): CC[A] = xs
+  def whatis[T: TypeTag](x: T): Unit = {
+    val tpe = typeOf[T]
+    val access = tpe.typeSymbol.asInstanceOf[scala.reflect.internal.HasFlags].accessString.replaceAllLiterally("package ", "")
+    println(f"$access%15s $tpe")
+  }
+
+  trait IntIterable extends p.Iterable[Int]
+  trait IntSet extends p.Set[Int]
+  trait IntSeq extends p.Seq[Int]
+
+  trait MutableIntSet extends p.m.Set[Int]
+  trait MutableIntSeq extends p.m.Seq[Int]
+
+  trait ImmutableIntSet extends p.i.Set[Int]
+  trait ImmutableIntSeq extends p.i.Seq[Int]
+
+  def f1: IntIterable = null
+  def f2: IntSet = null
+  def f3: IntSeq = null
+
+  def g1: MutableIntSet = null
+  def g2: MutableIntSeq = null
+  def g3: p.m.BitSet = null
+
+  def h1: ImmutableIntSeq = null
+  def h2: p.i.BitSet = null
+  def h3: p.i.IntSeq = null
+
+  def main(args: Array[String]): Unit = {
+    whatis(extract(f1))
+    whatis(extract(f2))
+    whatis(extract(f3))
+    whatis(extract(g1))
+    whatis(extract(g2))
+    whatis(extract(g3))
+    whatis(extract(h1))
+    whatis(extract(h2))
+    whatis(extract(h3))
+
+    whatis(extract(if (true) f1 else f2))
+    whatis(extract(if (true) f1 else f3))
+    whatis(extract(if (true) f1 else g1))
+    whatis(extract(if (true) f1 else g2))
+    whatis(extract(if (true) f1 else g3))
+    whatis(extract(if (true) f1 else h1))
+    whatis(extract(if (true) f1 else h2))
+    whatis(extract(if (true) f1 else h3))
+    whatis(extract(if (true) f2 else f3))
+    whatis(extract(if (true) f2 else g1))
+    whatis(extract(if (true) f2 else g2))
+    whatis(extract(if (true) f2 else g3))
+    whatis(extract(if (true) f2 else h1))
+    whatis(extract(if (true) f2 else h2))
+    whatis(extract(if (true) f2 else h3))
+    whatis(extract(if (true) f3 else g1))
+    whatis(extract(if (true) f3 else g2))
+    whatis(extract(if (true) f3 else g3))
+    whatis(extract(if (true) f3 else h1))
+    whatis(extract(if (true) f3 else h2))
+    whatis(extract(if (true) f3 else h3))
+    whatis(extract(if (true) g1 else g2))
+    whatis(extract(if (true) g1 else g3))
+    whatis(extract(if (true) g1 else h1))
+    whatis(extract(if (true) g1 else h2))
+    whatis(extract(if (true) g1 else h3))
+    whatis(extract(if (true) g2 else g3))
+    whatis(extract(if (true) g2 else h1))
+    whatis(extract(if (true) g2 else h2))
+    whatis(extract(if (true) g2 else h3))
+    whatis(extract(if (true) g3 else h1))
+    whatis(extract(if (true) g3 else h2))
+    whatis(extract(if (true) g3 else h3))
+    whatis(extract(if (true) h1 else h2))
+    whatis(extract(if (true) h1 else h3))
+    whatis(extract(if (true) h2 else h3))
+
+    whatis(extract(Nil))
+    whatis(extract(Vector()))
+    whatis(extract(Map[Int,Int]()))
+    whatis(extract(Set[Int]()))
+    whatis(extract(Seq[Int]()))
+    whatis(extract(Array[Int]()))
+    whatis(extract(scala.collection.immutable.BitSet(1)))
+    whatis(extract("abc"))
+    whatis(extract(if (true) Stream(1) else List(1)))
+    whatis(extract(if (true) Seq(1) else Set(1)))
+  }
+}