Closed
Description
The following code passes type checking, but fails the pickling.
trait T { self: {type M = Int} =>
type T = self.M
def lift(x: Int): T = x
}
class Test {
val t = new T {
type M = Int
}
t.lift(1): t.T
}error log
cannot take signature of (x: Int): Test.this.t.T exception occurred while compiling examples/opaque.scala Exception in thread "main" dotty.tools.dotc.core.MissingType: at dotty.tools.dotc.core.TypeErasure.dotty$tools$dotc$core$TypeErasure$$sigName(TypeErasure.scala:534) at dotty.tools.dotc.core.TypeErasure.dotty$tools$dotc$core$TypeErasure$$sigName(TypeErasure.scala:567) at dotty.tools.dotc.core.TypeErasure.dotty$tools$dotc$core$TypeErasure$$sigName(TypeErasure.scala:540) at dotty.tools.dotc.core.TypeErasure$.sigName(TypeErasure.scala:143) at dotty.tools.dotc.core.Signature$.apply(Signature.scala:128) at dotty.tools.dotc.core.Types$MethodicType.resultSignature(Types.scala:2699) at dotty.tools.dotc.core.Types$MethodType.computeSignature(Types.scala:2990) at dotty.tools.dotc.core.Types$SignatureCachingType.signature(Types.scala:2687) at dotty.tools.dotc.core.Types$MethodOrPoly.signature(Types.scala:2838) at dotty.tools.dotc.core.Denotations$SingleDenotation.signature(Denotations.scala:696) at dotty.tools.dotc.core.Types$NamedType.computeSignature(Types.scala:1696) at dotty.tools.dotc.core.Types$SignatureCachingType.signature(Types.scala:2687) at dotty.tools.dotc.core.Types$NamedType.signature(Types.scala:1653) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree(TreePickler.scala:366) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree$$anonfun$2(TreePickler.scala:377) at scala.compat.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12) at dotty.tools.dotc.core.tasty.TreePickler.withLength(TreePickler.scala:43) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree(TreePickler.scala:379) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree$$anonfun$5(TreePickler.scala:408) at scala.compat.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12) at dotty.tools.dotc.core.tasty.TreePickler.withLength(TreePickler.scala:43) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree(TreePickler.scala:408) at dotty.tools.dotc.core.tasty.TreePickler.pickleStats$$anonfun$2(TreePickler.scala:326) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:18) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:10) at scala.collection.immutable.List.foreach(List.scala:388) at dotty.tools.dotc.core.tasty.TreePickler.pickleStats(TreePickler.scala:326) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree$$anonfun$25(TreePickler.scala:520) at scala.compat.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12) at dotty.tools.dotc.core.tasty.TreePickler.withLength(TreePickler.scala:43) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree(TreePickler.scala:521) at dotty.tools.dotc.core.tasty.TreePickler.pickleDef$$anonfun$2(TreePickler.scala:302) at scala.compat.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12) at dotty.tools.dotc.core.tasty.TreePickler.withLength(TreePickler.scala:43) at dotty.tools.dotc.core.tasty.TreePickler.pickleDef(TreePickler.scala:307) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree(TreePickler.scala:491) at dotty.tools.dotc.core.tasty.TreePickler.pickleStats$$anonfun$2(TreePickler.scala:326) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:18) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:10) at scala.collection.immutable.List.foreach(List.scala:388) at dotty.tools.dotc.core.tasty.TreePickler.pickleStats(TreePickler.scala:326) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree$$anonfun$27(TreePickler.scala:527) at scala.compat.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12) at dotty.tools.dotc.core.tasty.TreePickler.withLength(TreePickler.scala:43) at dotty.tools.dotc.core.tasty.TreePickler.pickleTree(TreePickler.scala:527) at dotty.tools.dotc.core.tasty.TreePickler.pickle$$anonfun$1(TreePickler.scala:675) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:18) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:10) at scala.collection.immutable.List.foreach(List.scala:388) at dotty.tools.dotc.core.tasty.TreePickler.pickle(TreePickler.scala:675) at dotty.tools.dotc.transform.Pickler.run$$anonfun$7$$anonfun$5(Pickler.scala:56) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:18) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:10) at scala.collection.immutable.List.foreach(List.scala:388) at dotty.tools.dotc.transform.Pickler.run$$anonfun$2(Pickler.scala:79) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:18) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:10) at scala.collection.immutable.List.foreach(List.scala:388) at dotty.tools.dotc.transform.Pickler.run(Pickler.scala:79) at dotty.tools.dotc.core.Phases$Phase.runOn$$anonfun$1(Phases.scala:299) at scala.collection.immutable.List.map(List.scala:282) at dotty.tools.dotc.core.Phases$Phase.runOn(Phases.scala:301) at dotty.tools.dotc.transform.Pickler.runOn(Pickler.scala:83) at dotty.tools.dotc.Run.runPhases$4$$anonfun$4(Run.scala:175) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:18) at scala.compat.java8.JProcedure1.apply(JProcedure1.java:10) at scala.collection.IndexedSeqOptimized.foreach(IndexedSeqOptimized.scala:32) at scala.collection.IndexedSeqOptimized.foreach$(IndexedSeqOptimized.scala:29) at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:194) at dotty.tools.dotc.Run.runPhases$5(Run.scala:187) at dotty.tools.dotc.Run.compileUnits$$anonfun$1(Run.scala:195) at scala.compat.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12) at dotty.tools.dotc.util.Stats$.maybeMonitored(Stats.scala:90) at dotty.tools.dotc.Run.compileUnits(Run.scala:202) at dotty.tools.dotc.Run.compileSources(Run.scala:137) at dotty.tools.dotc.Run.compile(Run.scala:121) at dotty.tools.dotc.Driver.doCompile(Driver.scala:31) at dotty.tools.dotc.Driver.process(Driver.scala:134) at dotty.tools.dotc.Driver.process(Driver.scala:103) at dotty.tools.dotc.Driver.process(Driver.scala:115) at dotty.tools.dotc.Driver.main(Driver.scala:142) at dotty.tools.dotc.Main.main(Main.scala)