scalac backend crashes on Java nested interface

[scabug]

OuterInterface.java:

public interface OuterInterface {
    public interface NestedInterface {
    }
}

OuterClass.java:

public class OuterClass implements OuterInterface {
    public class InnerClass implements NestedInterface {
    }
}

Test.scala:

class Test {
  val x: OuterClass = null
}

Result:

$ javac OuterInterface.java
$ scalac -cp . OuterClass.java Test.scala
java.lang.AssertionError: assertion failed: Invalid interfaces in LOuterClass$InnerClass;: List(Ljava/lang/Object;)
        at scala.tools.nsc.backend.jvm.BTypes$ClassBType.checkInfoConsistency(BTypes.scala:893)
        at scala.tools.nsc.backend.jvm.BTypes$ClassBType.info_$eq(BTypes.scala:868)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.setClassInfo(BTypesFromSymbols.scala:446)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.$anonfun$classBTypeFromSymbol$5(BTypesFromSymbols.scala:126)
        at scala.collection.MapLike.getOrElse(MapLike.scala:128)
        at scala.collection.MapLike.getOrElse$(MapLike.scala:126)
        at scala.collection.concurrent.TrieMap.getOrElse(TrieMap.scala:631)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.classBTypeFromSymbol(BTypesFromSymbols.scala:118)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.$anonfun$setClassInfo$17(BTypesFromSymbols.scala:440)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.setClassInfo(BTypesFromSymbols.scala:440)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.$anonfun$classBTypeFromSymbol$5(BTypesFromSymbols.scala:126)
        at scala.collection.MapLike.getOrElse(MapLike.scala:128)
        at scala.collection.MapLike.getOrElse$(MapLike.scala:126)
        at scala.collection.concurrent.TrieMap.getOrElse(TrieMap.scala:631)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.classBTypeFromSymbol(BTypesFromSymbols.scala:118)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.$anonfun$typeToBType$1(BTypesFromSymbols.scala:177)
        at scala.collection.MapLike.getOrElse(MapLike.scala:128)
        at scala.collection.MapLike.getOrElse$(MapLike.scala:126)
        at scala.collection.AbstractMap.getOrElse(Map.scala:59)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.primitiveOrClassToBType$1(BTypesFromSymbols.scala:177)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.typeToBType(BTypesFromSymbols.scala:192)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.methodBTypeFromMethodType(BTypesFromSymbols.scala:146)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.methodBTypeFromSymbol(BTypesFromSymbols.scala:137)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.$anonfun$buildInlineInfoFromClassSymbol$5(BTypesFromSymbols.scala:583)
        at scala.collection.Iterator$$anon$11.nextCur(Iterator.scala:473)
        at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:479)
        at scala.collection.Iterator.foreach(Iterator.scala:929)
        at scala.collection.Iterator.foreach$(Iterator.scala:929)
        at scala.collection.AbstractIterator.foreach(Iterator.scala:1406)
        at scala.collection.TraversableOnce.toMap(TraversableOnce.scala:316)
        at scala.collection.TraversableOnce.toMap$(TraversableOnce.scala:314)
        at scala.collection.AbstractIterator.toMap(Iterator.scala:1406)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.buildInlineInfoFromClassSymbol(BTypesFromSymbols.scala:616)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.buildFromSymbol$1(BTypesFromSymbols.scala:522)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.buildInlineInfo(BTypesFromSymbols.scala:527)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.setClassInfo(BTypesFromSymbols.scala:444)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.$anonfun$classBTypeFromSymbol$5(BTypesFromSymbols.scala:126)
        at scala.collection.MapLike.getOrElse(MapLike.scala:128)
        at scala.collection.MapLike.getOrElse$(MapLike.scala:126)
        at scala.collection.concurrent.TrieMap.getOrElse(TrieMap.scala:631)
        at scala.tools.nsc.backend.jvm.BTypesFromSymbols.classBTypeFromSymbol(BTypesFromSymbols.scala:118)
        at scala.tools.nsc.backend.jvm.BCodeSkelBuilder$PlainSkelBuilder.genPlainClass(BCodeSkelBuilder.scala:94)
        at scala.tools.nsc.backend.jvm.GenBCode$BCodePhase$Worker1.visit(GenBCode.scala:190)
        at scala.tools.nsc.backend.jvm.GenBCode$BCodePhase$Worker1.$anonfun$run$1(GenBCode.scala:139)
        at scala.tools.nsc.backend.jvm.GenBCode$BCodePhase$Worker1.run(GenBCode.scala:139)
        at scala.tools.nsc.backend.jvm.GenBCode$BCodePhase.buildAndSendToDisk(GenBCode.scala:381)
        at scala.tools.nsc.backend.jvm.GenBCode$BCodePhase.run(GenBCode.scala:350)
        at scala.tools.nsc.Global$Run.compileUnitsInternal(Global.scala:1418)
        at scala.tools.nsc.Global$Run.compileUnits(Global.scala:1403)
        at scala.tools.nsc.Global$Run.compileSources(Global.scala:1398)
        at scala.tools.nsc.Global$Run.compile(Global.scala:1492)
        at scala.tools.nsc.MainClass.doCompile(Main.scala:24)
        at scala.tools.nsc.Driver.process(Driver.scala:55)
        at scala.tools.nsc.Driver.main(Driver.scala:68)
        at scala.tools.nsc.Main.main(Main.scala)
error: Error while emitting Test.scala
assertion failed: Invalid interfaces in LOuterClass$InnerClass;: List(Ljava/lang/Object;)
one error found

The problem goes away when:

• OuterClass.java refers to NestedInterface as OuterInterface.NestedInterface:

public class OuterClass implements OuterInterface {
    public class InnerClass implements OuterInterface.NestedInterface {
    }
}

• all the files are compiled in one run:

$ scalac OuterInterface.java OuterClass.java Test.scala

• Test.scala is compiled separately from OuterClass.java, e.g.

$ javac OuterInterface.java OuterClass.java
$ scalac -cp . Test.scala

So I suppose this must be a problem with the Java parser built into scalac that is used during mixed Java-Scala compilation.

[scabug]

Imported From: https://issues.scala-lang.org/browse/SI-10241?orig=1
Reporter: @ghik
Affected Versions: 2.12.1
See #10107

[scabug]

@SethTisue said:
duplicate of SI-10107?

[scabug]

@lrytz said:
yep..