Merge pull request #3647 from densh/si/8411

SI-8411 match desugared partial functions

5 files changed, 39 insertions, 4 deletions

diff --git a/src/reflect/scala/reflect/api/Internals.scala b/src/reflect/scala/reflect/api/Internals.scala
index 9faba7efd7..7788dba63e 100644
--- a/src/reflect/scala/reflect/api/Internals.scala
+++ b/src/reflect/scala/reflect/api/Internals.scala
@@ -765,7 +765,7 @@ trait Internals { self: Universe =>
     val SyntacticPartialFunction: SyntacticPartialFunctionExtractor
     trait SyntacticPartialFunctionExtractor {
       def apply(cases: List[Tree]): Match
-      def unapply(tree: Match): Option[List[CaseDef]]
+      def unapply(tree: Tree): Option[List[CaseDef]]
     }
 
     val SyntacticMatch: SyntacticMatchExtractor
diff --git a/src/reflect/scala/reflect/internal/ReificationSupport.scala b/src/reflect/scala/reflect/internal/ReificationSupport.scala
index 9a130337b4..f9f93fbff0 100644
--- a/src/reflect/scala/reflect/internal/ReificationSupport.scala
+++ b/src/reflect/scala/reflect/internal/ReificationSupport.scala
@@ -6,7 +6,7 @@ import Flags._
 import util._
 
 trait ReificationSupport { self: SymbolTable =>
-  import definitions.{TupleClass, FunctionClass, ScalaPackage, UnitClass}
+  import definitions._
   import internal._
 
   class ReificationSupportImpl extends ReificationSupportApi {
@@ -852,9 +852,25 @@ trait ReificationSupport { self: SymbolTable =>
 
     object SyntacticPartialFunction extends SyntacticPartialFunctionExtractor {
       def apply(cases: List[Tree]): Match = Match(EmptyTree, mkCases(cases))
-      def unapply(tree: Match): Option[List[CaseDef]] = tree match {
+      def unapply(tree: Tree): Option[List[CaseDef]] = tree match {
         case Match(EmptyTree, cases) => Some(cases)
-        case _                       => None
+        case Typed(
+               Block(
+                 List(ClassDef(clsMods, tpnme.ANON_FUN_NAME, Nil, Template(
+                   List(abspf: TypeTree, ser: TypeTree), noSelfType, List(
+                     DefDef(_, nme.CONSTRUCTOR, _, _, _, _),
+                     DefDef(_, nme.applyOrElse, _, _, _,
+                       Match(_, cases :+
+                         CaseDef(Bind(nme.DEFAULT_CASE, Ident(nme.WILDCARD)), _, _))),
+                     DefDef(_, nme.isDefinedAt, _, _, _, _))))),
+                 Apply(Select(New(Ident(tpnme.ANON_FUN_NAME)), termNames.CONSTRUCTOR), List())),
+               pf: TypeTree)
+          if pf.tpe != null && pf.tpe.typeSymbol.eq(PartialFunctionClass) &&
+             abspf.tpe != null && abspf.tpe.typeSymbol.eq(AbstractPartialFunctionClass) &&
+             ser.tpe != null && ser.tpe.typeSymbol.eq(SerializableClass) &&
+             clsMods.hasFlag(FINAL) && clsMods.hasFlag(SYNTHETIC) =>
+          Some(cases)
+        case _ => None
       }
     }
 
diff --git a/test/files/pos/t8411/Macros_1.scala b/test/files/pos/t8411/Macros_1.scala
new file mode 100644
index 0000000000..c5319c559c
--- /dev/null
+++ b/test/files/pos/t8411/Macros_1.scala
@@ -0,0 +1,10 @@
+import scala.language.experimental.macros
+import scala.reflect.macros.blackbox.Context
+
+object Macros {
+  def defaultZeroCase(pf: PartialFunction[Int, Int]): PartialFunction[Int, Int] = macro impl
+  def impl(c: Context)(pf: c.Tree) = { import c.universe._
+    val q"{ case ..$cases }" = pf
+    q"{ case ..$cases case _ => 0 }"
+  }
+}
diff --git a/test/files/pos/t8411/Test_2.scala b/test/files/pos/t8411/Test_2.scala
new file mode 100644
index 0000000000..a0ad30f0f5
--- /dev/null
+++ b/test/files/pos/t8411/Test_2.scala
@@ -0,0 +1,4 @@
+object Test extends App {
+  val pf = Macros.defaultZeroCase { case 1 => 2 }
+  assert(pf(2) == 0)
+}
diff --git a/test/files/scalacheck/quasiquotes/TypecheckedProps.scala b/test/files/scalacheck/quasiquotes/TypecheckedProps.scala
index 7c4cb0306e..fb2eb69321 100644
--- a/test/files/scalacheck/quasiquotes/TypecheckedProps.scala
+++ b/test/files/scalacheck/quasiquotes/TypecheckedProps.scala
@@ -152,4 +152,9 @@ object TypecheckedProps extends QuasiquoteProperties("typechecked") {
     assert(name == defName)
     assert(rhs ≈ defRhs)
   }
+
+  property("partial function") = test {
+    val q"{ case ..$cases }: $ascr" = typecheck(q"{ case 1 => () }: PartialFunction[Int, Unit]")
+    assert(cases ≈ q"{ case 1 => () }".cases)
+  }
 }