Added failing test for JsonIgnoreType with MixIn

[marceloverdijk]

As discussed on the user group http://jackson-users.ning.com/forum/topics/serializing-with-ignorejsontype-in-mixin-not-working

@JsonIgnoreType is not woorking with MixIns.

[cowtowncoder]

Thank you! I will try to figure out what is going on here.

[cowtowncoder]

Ah ok. I can see the misunderstanding here -- meaning of @JsonIgnoreType is not quite what you expect. It does not change the default visibility of properties; rather, it makes any properties declared with that type to be ignored.
I modified the test, moved it in TestIgnoredTypes, and it works as intended.

What you may want to use instead, if you want to avoid including public properties by default is to use @JsonAutoDetect and set visibility to Visibility.NONE for all accessors (or at least getters and setters); this way only explicitly annotated properties are automatically detected.
An alternative is ObjectMapper.setVisibility() which can be used to define the baseline for all types; this is the most commonly used way.