When the

photo

property is null, hasPhoto() seems to return true and control goes to the next statement (Kotlin 1.2.60)

if you assign

null

to

photo

it becomes initialized, so this is correct. Although I wonder, how did you assign null to non-nullable property? Reflection?

Well, the property is not nullable, but my API sends a null value. So Gson apparently assigns null to the property and things go bad.

Is it necessary to use lateinit in this example?

I did it to avoid using ?. or !!, but I think I will remove it.

Optional value contain native analog “has…” )

Does it work if you remove

open

modifier?

If you've got an external API setting it to null anyway, using lateinit to avoid ?. just opens you up to problems because you've bypassed the null safety kotlin gives you

@Tony Hoyle Yes, I’ve changed it to nullable.

lateinit

was a really bad idea in this case. I hadn’t thought that gson could set it to null anyway.