Allow sequence literals in inline parameters

Author: nicolasstucki

compiler/src/dotty/tools/dotc/typer/Checking.scala

@@ -678,29 +678,39 @@ trait Checking {
     val purityLevel = if (isFinal) Idempotent else Pure
     tree.tpe.widenTermRefExpr match {
       case tp: ConstantType if exprPurity(tree) >= purityLevel => // ok
-      case tp =>
-        def isCaseClassApply(sym: Symbol): Boolean =
-          sym.name == nme.apply && sym.is(Synthetic) && sym.owner.is(Module) && sym.owner.companionClass.is(Case)
-        def isCaseClassNew(sym: Symbol): Boolean =
-          sym.isPrimaryConstructor && sym.owner.is(Case) && sym.owner.isStatic
-        def isCaseObject(sym: Symbol): Boolean = {
-          // TODO add alias to Nil in scala package
-          sym.is(Case) && sym.is(Module)
-        }
-        val allow =
-          ctx.erasedTypes ||
-          ctx.inInlineMethod ||
-          (tree.symbol.isStatic && isCaseObject(tree.symbol) || isCaseClassApply(tree.symbol)) ||
-          isCaseClassNew(tree.symbol)
-        if (!allow) ctx.error(em"$what must be a known value", tree.pos)
-        else {
-          def checkArgs(tree: Tree): Unit = tree match {
-            case Apply(fn, args) =>
-              args.foreach(arg => checkInlineConformant(arg, isFinal, what))
-              checkArgs(fn)
-            case _ =>
-          }
-          checkArgs(tree)
+      case _ =>
+        tree match {
+          case Typed(expr, _) =>
+            checkInlineConformant(expr, isFinal, what)
+          case SeqLiteral(elems, _) =>
+            elems.foreach(elem => checkInlineConformant(elem, isFinal, what))
+          case Apply(fn, List(arg)) if defn.WrapArrayMethods().contains(fn.symbol) =>
+            checkInlineConformant(arg, isFinal, what)
+          case _ =>
+            def isCaseClassApply(sym: Symbol): Boolean =
+              sym.name == nme.apply && sym.is(Synthetic) && sym.owner.is(Module) && sym.owner.companionClass.is(Case)
+            def isCaseClassNew(sym: Symbol): Boolean =
+              sym.isPrimaryConstructor && sym.owner.is(Case) && sym.owner.isStatic
+            def isCaseObject(sym: Symbol): Boolean = {
+              // TODO add alias to Nil in scala package
+              sym.is(Case) && sym.is(Module)
+            }
+            val allow =
+              ctx.erasedTypes ||
+              ctx.inInlineMethod ||
+              (tree.symbol.isStatic && isCaseObject(tree.symbol) || isCaseClassApply(tree.symbol)) ||
+              isCaseClassNew(tree.symbol)
+
+            if (!allow) ctx.error(em"$what must be a known value", tree.pos)
+            else {
+              def checkArgs(tree: Tree): Unit = tree match {
+                case Apply(fn, args) =>
+                  args.foreach(arg => checkInlineConformant(arg, isFinal, what))
+                  checkArgs(fn)
+                case _ =>
+              }
+              checkArgs(tree)
+            }
         }
     }
   }