make coll. wrapper classes usable by other libs; seq alias variance

Author: Sciss

src/main/scala-2.12/scala/swing/BufferWrapper.scala

@@ -13,7 +13,7 @@ import scala.collection.{Iterator, mutable}
 /**
  * Default partial implementation for buffer adapters.
  */
-protected[swing] abstract class BufferWrapper[A] extends mutable.Buffer[A] {
+abstract class BufferWrapper[A] extends mutable.Buffer[A] {
   // abstract
 
   def addOne(elem: A): this.type
@@ -22,6 +22,8 @@ protected[swing] abstract class BufferWrapper[A] extends mutable.Buffer[A] {
 
   // impl
 
+  type MoreElem[+B] = Traversable[B]
+
   final override def +=(elem: A): this.type = addOne(elem)
 
   override def clear(): Unit = for (_ <- 0 until length) remove(0)
@@ -31,7 +33,7 @@ protected[swing] abstract class BufferWrapper[A] extends mutable.Buffer[A] {
     insert(n, a)
   }
 
-  override def insertAll(n: Int, elems: Traversable[A]): Unit = {
+  override def insertAll(n: Int, elems: MoreElem[A]): Unit = {
     var i = n
     for (el <- elems) {
       insert(i, el)

src/main/scala-2.12/scala/swing/MapWrapper.scala

@@ -5,7 +5,7 @@ import scala.collection.mutable
 /**
   * Default partial implementation for set adapters.
   */
-protected[swing] abstract class MapWrapper[K, V] extends mutable.Map[K, V] {
+abstract class MapWrapper[K, V] extends mutable.Map[K, V] {
   // abstract
 
   def addOne      (elem: (K, V)): this.type

src/main/scala-2.12/scala/swing/SetWrapper.scala

@@ -5,7 +5,7 @@ import scala.collection.mutable
 /**
   * Default partial implementation for set adapters.
   */
-protected[swing] abstract class SetWrapper[A] extends mutable.Set[A] {
+abstract class SetWrapper[A] extends mutable.Set[A] {
   // abstract
 
   def addOne      (elem: A): this.type

src/main/scala-2.13.0-M5/scala/swing/BufferWrapper.scala

@@ -13,7 +13,9 @@ import scala.collection.{Iterator, mutable}
 /**
  * Default partial implementation for buffer adapters.
  */
-protected[swing] abstract class BufferWrapper[A] extends mutable.Buffer[A] {
+abstract class BufferWrapper[A] extends mutable.Buffer[A] {
+  type MoreElem[+B] = IterableOnce[B]
+
   override def clear(): Unit = for (_ <- 0 until length) remove(0)
 
   override def update(n: Int, a: A): Unit = {
@@ -25,7 +27,7 @@ protected[swing] abstract class BufferWrapper[A] extends mutable.Buffer[A] {
 
   override def prepend(elem: A): this.type = { insert(0, elem); this }
 
-  override def insertAll(idx: Int, elems: IterableOnce[A]): Unit = {
+  override def insertAll(idx: Int, elems: MoreElem[A]): Unit = {
     var i = idx
     for (el <- elems.iterator) {
       insert(i, el)

src/main/scala-2.13.0-M5/scala/swing/MapWrapper.scala

@@ -2,4 +2,4 @@ package scala.swing
 
 import scala.collection.mutable
 
-protected[swing] abstract class MapWrapper[K, V] extends mutable.Map[K, V]
+abstract class MapWrapper[K, V] extends mutable.Map[K, V]

src/main/scala-2.13.0-M5/scala/swing/SetWrapper.scala

@@ -2,4 +2,4 @@ package scala.swing
 
 import scala.collection.mutable
 
-protected[swing] abstract class SetWrapper[A] extends mutable.Set[A]
+abstract class SetWrapper[A] extends mutable.Set[A]

src/main/scala/scala/swing/package.scala

@@ -22,7 +22,7 @@ package object swing {
   type Image      = java.awt.Image
   type Font       = java.awt.Font
 
-  type Seq[A]     = scala.collection.Seq[A] // because scala.Seq differs between Scala 2.12 and 2.13
+  type Seq[+A]    = scala.collection.Seq[A] // because scala.Seq differs between Scala 2.12 and 2.13
 
   implicit lazy val reflectiveCalls     = scala.language.reflectiveCalls
   implicit lazy val implicitConversions = scala.language.implicitConversions