There is a regression in `JsonTypeInfo` processing in `3.0`

[k163377]

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Describe the bug

The following test succeeds on the 2.19, but fails on master (= 3.0).
https://github.com/FasterXML/jackson-module-kotlin/blob/2.19/src/test/kotlin/com/fasterxml/jackson/module/kotlin/test/github/GitHub844.kt

The stack trace is as follows

tools.jackson.databind.exc.InvalidTypeIdException: Could not resolve type id 'ChildClass' as a subtype of `tools.jackson.module.kotlin.test.github.BaseClass`: known type ids = []
 at [Source: REDACTED (`StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION` disabled); byte offset: #UNKNOWN]

	at tools.jackson.databind.exc.InvalidTypeIdException.from(InvalidTypeIdException.java:41)
	at tools.jackson.databind.DeserializationContext.invalidTypeIdException(DeserializationContext.java:2037)
	at tools.jackson.databind.DeserializationContext.handleUnknownTypeId(DeserializationContext.java:1614)
	at tools.jackson.databind.jsontype.impl.TypeDeserializerBase._handleUnknownTypeId(TypeDeserializerBase.java:279)
	at tools.jackson.databind.jsontype.impl.TypeDeserializerBase._findDeserializer(TypeDeserializerBase.java:160)
	at tools.jackson.databind.jsontype.impl.AsPropertyTypeDeserializer._deserializeTypedForId(AsPropertyTypeDeserializer.java:119)
	at tools.jackson.databind.jsontype.impl.AsPropertyTypeDeserializer.deserializeTypedFromObject(AsPropertyTypeDeserializer.java:103)
	at tools.jackson.databind.deser.AbstractDeserializer.deserializeWithType(AbstractDeserializer.java:243)
	at tools.jackson.databind.deser.impl.TypeWrappedDeserializer.deserialize(TypeWrappedDeserializer.java:72)
	at tools.jackson.databind.deser.DeserializationContextExt.readRootValue(DeserializationContextExt.java:265)
	at tools.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:2576)
	at tools.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:1591)
	at tools.jackson.module.kotlin.test.github.GitHub844.test(GitHub844.kt:31)
	at java.base/java.lang.reflect.Method.invoke(Method.java:569)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)

Version Information

3.0

Reproduction

https://github.com/FasterXML/jackson-module-kotlin/blob/master/src/test/kotlin/tools/jackson/module/kotlin/test/github/GitHub844.kt

Expected behavior

It succeeds as well as the 2.19.

Additional context

Sorry, I am concentrating on other work and have not been able to analyze the error.

Also, the reason why this was not detected by CI was because some tests of kotlin-module were not executed by the verify command.
This problem existed for a long time (before I became the maintainer), but I was unaware of it because I was testing locally using Intellij.
This problem has already been resolved.
FasterXML/jackson-module-kotlin#900

[cowtowncoder]

Unfortunately I think I'll need a Java translation here -- I don't know how sealed classes translate from Kotlin. I tried to convert the test, but as-is it can't work even on 2.19 because...
Specifically in this case I don't know how/where sub-class relationship would be available: on Java side it's either via @JsonSubTypes annotation, or ObjectMapper.registerSubtypes().

I am guessing that is something Kotlin module will provide.

Oh, actually, yes, KotlinAnnotationIntrospector.kt has:

    /**
     * Subclasses can be detected automatically for sealed classes, since all possible subclasses are known
     * at compile-time to Kotlin. This makes [com.fasterxml.jackson.annotation.JsonSubTypes] redundant.
     */
    override fun findSubtypes(cfg : MapperConfig<*>, a: Annotated): MutableList<NamedType>? = a.rawType
    ....

so that's the mechanism. But somehow that fails to provide subtypes in 3.0 it sounds like.

[k163377]

I'm really sorry, it was actually caused by a failure in kotlin-module to merge to master.
It will be fixed in FasterXML/jackson-module-kotlin#911 .

[cowtowncoder]

@k163377 Not to worry, it's all good! I'm just happy problem is resolved :)

Thank you following up.