diff options
| -rw-r--r-- | src/dotty/tools/dotc/typer/RefChecks.scala | 13 | ||||
| -rw-r--r-- | tests/neg/final-sealed.scala | 4 |
2 files changed, 14 insertions, 3 deletions
diff --git a/src/dotty/tools/dotc/typer/RefChecks.scala b/src/dotty/tools/dotc/typer/RefChecks.scala index 3633a7279..d9b62badc 100644 --- a/src/dotty/tools/dotc/typer/RefChecks.scala +++ b/src/dotty/tools/dotc/typer/RefChecks.scala @@ -71,10 +71,17 @@ object RefChecks { } } - /** Check that self type of this class conforms to self types of parents */ - private def checkSelfType(clazz: Symbol)(implicit ctx: Context): Unit = clazz.info match { + /** Check that final and sealed restrictions on class parents + * and that self type of this class conforms to self types of parents. + */ + private def checkParents(clazz: Symbol)(implicit ctx: Context): Unit = clazz.info match { case cinfo: ClassInfo => for (parent <- cinfo.classParents) { + val pclazz = parent.classSymbol + if (pclazz.is(Final)) + ctx.error(d"cannot extend final $pclazz", clazz.pos) + if (pclazz.is(Sealed) && pclazz.associatedFile != clazz.associatedFile) + ctx.error(d"cannot extend sealed $pclazz in different compilation unit", clazz.pos) val pself = parent.givenSelfType.asSeenFrom(clazz.thisType, parent.classSymbol) if (pself.exists && !(cinfo.selfType <:< pself)) ctx.error(d"illegal inheritance: self type ${cinfo.selfType} of $clazz does not conform to self type $pself of parent ${parent.classSymbol}", clazz.pos) @@ -768,7 +775,7 @@ class RefChecks extends MiniPhase { thisTransformer => override def transformTemplate(tree: Template)(implicit ctx: Context, info: TransformerInfo) = { val cls = ctx.owner checkOverloadedRestrictions(cls) - checkSelfType(cls) + checkParents(cls) checkCompanionNameClashes(cls) checkAllOverrides(cls) checkAnyValSubclass(cls) diff --git a/tests/neg/final-sealed.scala b/tests/neg/final-sealed.scala new file mode 100644 index 000000000..017afd63b --- /dev/null +++ b/tests/neg/final-sealed.scala @@ -0,0 +1,4 @@ +final class A +class B extends A +class C extends Option[Int] + |