Extending @experimental tests+impl

I wanted to make sure `@annotation.experimental` worked, turns out it
already did, but adding to an existing test made me realise I need to
handle SHAREDtype.

Author: dwijnand

core/src/main/scala/com/typesafe/tools/mima/core/TastyReader.scala

@@ -9,8 +9,8 @@ final class TastyReader(val bytes: Array[Byte], start: Int, end: Int, val base:
 
   private[this] var bp: Int = start
 
-  def fork                           = new TastyReader(bytes, bp, end, base)
-  def forkAt(start: Addr, end: Addr) = new TastyReader(bytes, index(start), index(end), base)
+  def fork                = new TastyReader(bytes, bp, end, base)
+  def forkAt(start: Addr) = new TastyReader(bytes, index(start), end, base)
 
   def addr(idx: Int): Addr   = Addr(idx - base)
   def index(addr: Addr): Int = addr.index + base

core/src/main/scala/com/typesafe/tools/mima/core/TastyUnpickler.scala

@@ -64,14 +64,15 @@ object TastyUnpickler {
     }
   }
 
-  def unpickleTree(in: TastyReader, names: Names) = {
+  def unpickleTree(in: TastyReader, names: Names): Tree = {
     import in._
 
     def readName()         = names(readNat())
     def skipTree(tag: Int) = { skipTreeTagged(in, tag); UnknownTree(tag) }
     def readTypeRefPkg()   = TypeRefPkg(readName())                                 // fullyQualified_NameRef         -- A reference to a package member with given fully qualified name
     def readTypeRef()      = TypeRef(name = readName(), qual = readType())          // NameRef qual_Type              -- A reference `qual.name` to a non-local member
     def readAnnot()        = { readEnd(); Annot(readType(), skipTree(readByte())) } // tycon_Type fullAnnotation_Tree -- An annotation, given (class) type of constructor, and full application tree
+    def readSharedType()   = unpickleTree(forkAt(readAddr()), names).asInstanceOf[Type]
 
     def readPath() = readByte() match {
       case TERMREFpkg => readTypeRefPkg()
@@ -81,6 +82,7 @@ object TastyUnpickler {
     def readType(): Type = readByte() match {
       case TYPEREF    => readTypeRef()
       case TERMREFpkg => readTypeRefPkg()
+      case SHAREDtype => readSharedType()
       case tag        => skipTree(tag); UnknownType(tag)
     }
 
@@ -509,7 +511,7 @@ object TastyUnpickler {
       case PACKAGE    => readEnd(); readNames(packageName)
       case TERMREFpkg => readNames(readName())
       case TYPEREFpkg => readNames(readName())
-      case SHAREDtype => val r = forkAt(readAddr(), endAddr); r.readByte(); readNames(readName(r))
+      case SHAREDtype => val r = forkAt(readAddr()); r.readByte(); readNames(readName(r))
       case t          => skipTreeTagged(in, t); readNames(packageName)
     }
     readNames(nme.Empty)

functional-tests/src/test/changes-in-experimental-are-ok/app/App.scala

@@ -1,3 +1,3 @@
 object App {
-  def main(args: Array[String]): Unit = println(new pkg1.pkg2.Foo().foo)
+  def main(args: Array[String]): Unit = println(new pkg1.pkg2.Foo())
 }

functional-tests/src/test/changes-in-experimental-are-ok/testAppRun.pending

@@ -7,3 +7,8 @@ import scala.annotation.experimental2
 class Foo {
   def foo = 1
 }
+
+@annotation.experimental2
+class Bar {
+  def foo = 1
+}

functional-tests/src/test/changes-in-experimental-are-ok/v1/A.scala

@@ -5,5 +5,10 @@ import scala.annotation.experimental2
 
 @experimental2
 class Foo {
-  def bar = 2
+  def foo = "1"
+}
+
+@annotation.experimental2
+class Bar {
+  def foo = "1"
 }

functional-tests/src/test/changes-in-experimental-are-ok/v2/A.scala

@@ -1,2 +1,3 @@
 # Haven't implemented the ScalaSig unpickling part, only TASTy
-method foo()Int in class pkg1.pkg2.Foo does not have a correspondent in new version
+method foo()Int in class pkg1.pkg2.Foo has a different result type in new version, where it is java.lang.String rather than Int
+method bar()Int in class pkg1.pkg2.Foo has a different result type in new version, where it is java.lang.String rather than Int

functional-tests/src/test/changes-in-experimental-methods-are-ok/problems-2.12.txt

@@ -6,4 +6,7 @@ import scala.annotation.experimental2
 class Foo {
   @experimental2
   def foo = 1
+
+  @annotation.experimental2
+  def bar = 1
 }

functional-tests/src/test/changes-in-experimental-methods-are-ok/v1/A.scala

@@ -5,5 +5,8 @@ import scala.annotation.experimental2
 
 class Foo {
   @experimental2
+  def foo = "1"
+
+  @annotation.experimental2
   def bar = "1"
 }