Minor refactor typedNewFun

som-snytt · som-snytt · commit 88d0d0227393 · 2024-08-20T14:58:39.000-07:00
diff --git a/src/compiler/scala/tools/nsc/transform/UnCurry.scala b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
@@ -220,7 +220,7 @@ abstract class UnCurry extends InfoTransform
       // Normally, we can unwrap `() => cbn` to `cbn` where `cbn` refers to a CBN argument (typically `cbn` is an Ident),
       // because we know `cbn` will already be a `Function0` thunk. When we're targeting a SAM,
       // the types don't align and we must preserve the function wrapper.
-      if (fun.vparams.isEmpty && isByNameRef(fun.body) && fun.attachments.get[SAMFunction].isEmpty) {
+      if (fun.vparams.isEmpty && isByNameRef(fun.body) && !fun.attachments.contains[SAMFunction]) {
         noApply += fun.body
         fun.body
       }
@@ -236,27 +236,26 @@ abstract class UnCurry extends InfoTransform
         val newFun = deriveFunction(fun)(_ => localTyper.typedPos(fun.pos)(
           gen.mkForwarder(gen.mkAttributedRef(liftedMethod.symbol), (fun.vparams map (_.symbol)) :: Nil)
         ))
+        def typeNewFun = localTyper.typedPos(fun.pos)(Block(liftedMethod :: Nil, super.transform(newFun)))
 
         if (!mustExpand) {
           liftedMethod.symbol.updateAttachment(DelambdafyTarget)
           liftedMethod.updateAttachment(DelambdafyTarget)
+          typeNewFun
         }
-
-        val typedNewFun = localTyper.typedPos(fun.pos)(Block(liftedMethod :: Nil, super.transform(newFun)))
-        if (mustExpand) {
-          val Block(stats, expr : Function) = typedNewFun: @unchecked
-          val expansion = gen.expandFunction(localTyper)(expr, inConstructorFlag)
-          expansion match {
-            case Block(ClassDef(_, _, _, Template(_, _, body)) :: Nil, _) =>
-              body.last match {
-                case DefDef(_, _, _, _, _, Apply(_, args)) => noApply.addAll(args) // samDef args are pass-thru
-                case _ =>
-              }
-            case _ =>
-          }
-          treeCopy.Block(typedNewFun, stats, expansion)
-        } else {
-          typedNewFun
+        else typeNewFun match {
+          case typedNewFun @ Block(stats, expr: Function) =>
+            val expansion = gen.expandFunction(localTyper)(expr, inConstructorFlag)
+            expansion match {
+              case Block(ClassDef(_, _, _, Template(_, _, body)) :: Nil, _) =>
+                body.last match {
+                  case DefDef(_, _, _, _, _, Apply(_, args)) => noApply.addAll(args) // samDef args are pass-thru
+                  case _ =>
+                }
+              case _ =>
+            }
+            treeCopy.Block(typedNewFun, stats, expansion)
+          case x => throw new MatchError(x)
         }
       }
 
diff --git a/src/reflect/scala/reflect/macros/Attachments.scala b/src/reflect/scala/reflect/macros/Attachments.scala
@@ -66,8 +66,15 @@ abstract class Attachments { self =>
   }
 
   /** Check underlying payload contains an instance of type `T`. */
-  def contains[T: ClassTag]: Boolean =
-    !isEmpty && (all exists matchesTag[T])
+  def contains[T: ClassTag]: Boolean = !isEmpty && {
+    val it = all.iterator
+    val matchesTagFn = matchesTag[T]
+    while (it.hasNext) { // OPT: hotspot, hand roll `Set.exists`.
+      val datum = it.next()
+      if (matchesTagFn(datum)) return true
+    }
+    false
+  }
 
   /** Creates a copy of this attachment with the payload slot of T added/updated with the provided value.
    *  Replaces an existing payload of the same type, if exists.
