Merge pull request #4703 from dotty-staging/decompile-fix-empty-varargs

Do not print trailing comma for empty var args

Author: nicolasstucki

library/src/scala/tasty/util/ShowSourceCode.scala

@@ -300,8 +300,13 @@ class ShowSourceCode[T <: Tasty with Singleton](tasty0: T) extends Show[T](tasty
           case Term.Select(Term.This(_), "<init>", _) => this += "this" // call to constructor inside a constructor
           case _ => printTree(fn)
         }
+        val args1 = args match {
+          case init :+ Term.Typed(Term.Repeated(Nil), _) => init // drop empty var args at the end
+          case _ => args
+        }
+
         this += "("
-        printTrees(args, ", ")
+        printTrees(args1, ", ")
         this += ")"
 
       case Term.TypeApply(fn, args) =>

tests/pos/simple-repeated-args.decompiled

@@ -1,4 +1,5 @@
 /** Decompiled from out/posTestFromTasty/pos/simple-repeated-args/Foo.class */
 class Foo() {
   scala.List.apply[scala.Any](1, "2", '3')
+  scala.Array.apply(1)
 }

tests/pos/simple-repeated-args.scala

@@ -1,3 +1,4 @@
 class Foo {
   List(1, "2", '3')
+  Array(1)
 }