How do I handle an empty List in Grails/GORM?

Answer 1

In your test parent.children will always be null (children wont be initialized until you add the first one). So you could change your test to:

assertNull parent.children

The children will be initialized when you save the Parent (regardless if children are added) or when children are added. If you want it to always be initialized you can do it manually in the Parent when you define the children:

List<Children> children = new ArrayList<Children>()

Answer 2

i am getting similar results (maybe children stays null). note that you must be using an integration test for the gorm stuff to be around.

you can handle an empty list as follows:

parent.children?.each { println it}
parent.addToChildren(new Children(/* whatever you need */))
parent.children?.each { println it}