Fix for SI-5374.

Lists are now serialized so that the entire list structure is serialized, including list nodes.
This is different from the previous behaviour where only the elements were serialized.
List buffers are now optimized so that only the elements of the list are serialized, and
not the nodes of the internally maintained list.

4 files changed, 90 insertions, 22 deletions

diff --git a/src/library/scala/collection/immutable/List.scala b/src/library/scala/collection/immutable/List.scala
index c6f056bd81..e9ecc75e0f 100644
--- a/src/library/scala/collection/immutable/List.scala
+++ b/src/library/scala/collection/immutable/List.scala
@@ -316,28 +316,7 @@ final case class ::[B](private var hd: B, private[scala] var tl: List[B]) extend
   override def tail : List[B] = tl
   override def isEmpty: Boolean = false
 
-  import java.io._
 
-  private def writeObject(out: ObjectOutputStream) {
-    var xs: List[B] = this
-    while (!xs.isEmpty) { out.writeObject(xs.head); xs = xs.tail }
-    out.writeObject(ListSerializeEnd)
-  }
-
-  private def readObject(in: ObjectInputStream) {
-    hd = in.readObject.asInstanceOf[B]
-    assert(hd != ListSerializeEnd)
-    var current: ::[B] = this
-    while (true) in.readObject match {
-      case ListSerializeEnd =>
-        current.tl = Nil
-        return
-      case a : Any =>
-        val list : ::[B] = new ::(a.asInstanceOf[B], Nil)
-        current.tl = list
-        current = list
-    }
-  }
 }
 
 /** $factoryInfo
diff --git a/src/library/scala/collection/mutable/ListBuffer.scala b/src/library/scala/collection/mutable/ListBuffer.scala
index 131cdd0005..eb871135df 100644
--- a/src/library/scala/collection/mutable/ListBuffer.scala
+++ b/src/library/scala/collection/mutable/ListBuffer.scala
@@ -13,6 +13,7 @@ package mutable
 
 import generic._
 import immutable.{List, Nil, ::}
+import java.io._
 
 /** A `Buffer` implementation back up by a list. It provides constant time
  *  prepend and append. Most other operations are linear.
@@ -53,6 +54,7 @@ final class ListBuffer[A]
   override def companion: GenericCompanion[ListBuffer] = ListBuffer
 
   import scala.collection.Traversable
+  import scala.collection.immutable.ListSerializeEnd
 
   private var start: List[A] = Nil
   private var last0: ::[A] = _
@@ -60,7 +62,49 @@ final class ListBuffer[A]
   private var len = 0
 
   protected def underlying: immutable.Seq[A] = start
-
+  
+  private def writeObject(out: ObjectOutputStream) {
+    // write start
+    var xs: List[A] = start
+    while (!xs.isEmpty) { out.writeObject(xs.head); xs = xs.tail }
+    out.writeObject(ListSerializeEnd)
+    
+    // no need to write last0
+    
+    // write if exported
+    out.writeBoolean(exported)
+    
+    // write the length
+    out.writeInt(len)
+  }
+  
+  private def readObject(in: ObjectInputStream) {
+    // read start, set last0 appropriately
+    var elem: A = in.readObject.asInstanceOf[A]
+    if (elem == ListSerializeEnd) {
+      start = Nil
+      last0 = null
+    } else {
+      var current = new ::(elem, Nil)
+      start = current
+      elem = in.readObject.asInstanceOf[A]
+      while (elem != ListSerializeEnd) {
+        val list = new ::(elem, Nil)
+        current.tl = list
+        current = list
+        elem = in.readObject.asInstanceOf[A]
+      }
+      last0 = current
+      start
+    }
+    
+    // read if exported
+    exported = in.readBoolean()
+    
+    // read the length
+    len = in.readInt()
+  }
+  
   /** The current length of the buffer.
    *
    *  This operation takes constant time.
diff --git a/test/files/run/si5374.check b/test/files/run/si5374.check
new file mode 100644
index 0000000000..cdf0bc7e5b
--- /dev/null
+++ b/test/files/run/si5374.check
@@ -0,0 +1,3 @@
+ListBuffer(1, 2, 3, 1)
+ListBuffer(1, 2, 3, 1)
+ListBuffer()
\ No newline at end of file
diff --git a/test/files/run/si5374.scala b/test/files/run/si5374.scala
new file mode 100644
index 0000000000..a5678c3a81
--- /dev/null
+++ b/test/files/run/si5374.scala
@@ -0,0 +1,42 @@
+
+
+
+import collection.mutable.ListBuffer
+import java.io._
+
+
+
+object Test {
+  
+  def main(args: Array[String]) {
+    ticketExample()
+    emptyListBuffer()
+  }
+  
+  def ticketExample() {
+    val baos = new ByteArrayOutputStream
+    val oos = new ObjectOutputStream(baos)
+    oos.writeObject( ListBuffer(1,2,3) )
+    val bais = new ByteArrayInputStream( baos.toByteArray )
+    val ois = new ObjectInputStream(bais)
+    val lb = ois.readObject.asInstanceOf[ListBuffer[Int]]
+    val lb2 = ListBuffer[Int]() ++= lb
+    
+    lb2 ++= List(1)
+    lb ++= List(1)
+    println(lb)
+    println(lb2)
+  }
+  
+  def emptyListBuffer() {
+    val baos = new ByteArrayOutputStream
+    val oos = new ObjectOutputStream(baos)
+    oos.writeObject( ListBuffer() )
+    val bais = new ByteArrayInputStream( baos.toByteArray )
+    val ois = new ObjectInputStream(bais)
+    val lb = ois.readObject.asInstanceOf[ListBuffer[Int]]
+    
+    println(lb)
+  }
+  
+}