Jackson2: Super class did not get type information

[michaelzangl]

Jackson can (de)serialize instances of the hierarchy root class when using @JsonSubTypes. When generating interface for this java class:

    @JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "type")
    @JsonSubTypes(@JsonSubTypes.Type(NonAbstractRootSub.class))
    @JsonTypeName("rootType")
    public static class NonAbstractRoot {
    }

    @JsonTypeName("subType")
    public static class NonAbstractRootSub extends NonAbstractRoot {
    }

Previously wrong generated code ("rootType" missing):

interface NonAbstractRoot {
    type: "subType";
}

interface NonAbstractRootSub extends NonAbstractRoot {
    type: "subType";
}

type NonAbstractRootUnion = NonAbstractRootSub;

Correct:

interface NonAbstractRoot {
    type: "rootType" | "subType";
}

interface NonAbstractRootSub extends NonAbstractRoot {
    type: "subType";
}

type NonAbstractRootUnion = NonAbstractRootSub;

[vojtechhabarta]

Thanks for your pull request with good example.

While this fixes typescript-generator inconsistency with Jackson it can break some users code. I am not sure how frequent this problem could be but I think we need to change this sooner the better.

For users:

make root class abstract if you don't want discriminant value for this class to be included in union

[vojtechhabarta]

Released in v2.25.695.