Fix varargs in macros

compiler/src/dotty/tools/dotc/transform/Splicer.scala

@@ -102,6 +102,9 @@ object Splicer {
     protected def interpretLiteral(value: Any)(implicit env: Env): Object =
       value.asInstanceOf[Object]
 
+    protected def interpretVarargs(args: List[Object])(implicit env: Env): Object =
+      args.toSeq
+
     protected def interpretTastyContext()(implicit env: Env): Object =
       new TastyImpl(ctx) {
         override def rootPosition: SourcePosition = pos
@@ -240,6 +243,7 @@ object Splicer {
     def interpretQuote(tree: tpd.Tree)(implicit env: Env): Boolean = true
     def interpretTypeQuote(tree: tpd.Tree)(implicit env: Env): Boolean = true
     def interpretLiteral(value: Any)(implicit env: Env): Boolean = true
+    def interpretVarargs(args: List[Boolean])(implicit env: Env): Boolean = args.forall(identity)
     def interpretTastyContext()(implicit env: Env): Boolean = true
     def interpretStaticMethodCall(fn: tpd.Tree, args: => List[Boolean])(implicit env: Env): Boolean = args.forall(identity)
 
@@ -259,6 +263,7 @@ object Splicer {
     protected def interpretQuote(tree: Tree)(implicit env: Env): Result
     protected def interpretTypeQuote(tree: Tree)(implicit env: Env): Result
     protected def interpretLiteral(value: Any)(implicit env: Env): Result
+    protected def interpretVarargs(args: List[Result])(implicit env: Env): Result
     protected def interpretTastyContext()(implicit env: Env): Result
     protected def interpretStaticMethodCall(fn: Tree, args: => List[Result])(implicit env: Env): Result
     protected def unexpectedTree(tree: Tree)(implicit env: Env): Result
@@ -293,7 +298,10 @@ object Splicer {
 
       case Inlined(EmptyTree, Nil, expansion) => interpretTree(expansion)
 
-      case _ => unexpectedTree(tree)
+      case Typed(SeqLiteral(elems, _), _) => interpretVarargs(elems.map(e => interpretTree(e)))
+
+      case _ =>
+        unexpectedTree(tree)
     }
 
     object StaticMethodCall {

compiler/test/dotc/run-test-pickling.blacklist

@@ -20,6 +20,7 @@ i4803d
 i4803e
 i4803f
 i4947b
+inline-varargs-1
 implicitShortcut
 lazy-implicit-lists.scala
 lazy-implicit-nums.scala

tests/run/inline-varargs-1.check

@@ -0,0 +1 @@
+6

tests/run/inline-varargs-1/Macro_1.scala

@@ -0,0 +1,6 @@
+
+import scala.quoted._
+
+object Macros {
+  def sum(nums: Int*): Expr[Int] = nums.sum.toExpr
+}

tests/run/inline-varargs-1/Main_2.scala

@@ -0,0 +1,9 @@
+
+object Test {
+
+  def main(args: Array[String]): Unit = {
+    println(sum(1, 2, 3))
+  }
+
+  inline def sum(inline i: Int, inline j: Int, inline k: Int): Int = ~Macros.sum(i, j, k)
+}