Deprecated the @serializable annotation, introd...

Deprecated the @serializable annotation, introduce a new trait
"scala.Serializable" which has to be extended instead (cross-platform).

Known issues:
 - Companion objects of serializable classes (including case classes) are automatically made serializable. However, they don't extend "Serializable" statically because of the known difficulty (should be done before typing, but hard).
 - Writing "case class C() extends Serializable" gives "error: trait Serializable is inherited twice"
 - Functions are serializable, but don't extend Serializable dynamically (could be fixed by making FunctionN Serializable - shouldn't we?)

Note that @SerialVersionUID continues to be an annotation; it generates
a static field, which is not possible otherwise in scala.

Review by dragos, extempore.

Question to dragos: in JavaPlatform.isMaybeBoxed, why is there a test
for "JavaSerializableClass"? Is that correct?

1 files changed, 6 insertions, 0 deletions

diff --git a/test/files/pos/t3924.scala b/test/files/pos/t3924.scala
new file mode 100644
index 0000000000..35165baaf0
--- /dev/null
+++ b/test/files/pos/t3924.scala
@@ -0,0 +1,6 @@
+object Test {
+  class Hoe extends Serializable {
+    def add(a: java.io.Serializable): Unit = println(a)
+    def someMethod() { add(this) }
+  }
+}