Unfortunately this contrasts with the current behaviour that null-->NaN for a floating-point number, rather than being the default number input. In standard JSON, the float values NaN, Infinity and -Infinity have to become null, and to convert them back to a default value doesn't make sense. We could add an option to "ignore null items" which would treat nulls as equivalent to that item not existing.
Ok this is so random how I found this, but I was able to reproduce it. I'm hoping others on here can reproduce it as well. If this is a known issue then please link to the source for reference. I've attached code that reproduces it.
But basically in order to reproduce it:
Place a Map datatype in the private class data of the class.
Make the Map datatype a typedef.
lava.zip