Strange behavior with fragments

[mvid]

We are seeing some strange behavior with null fields and fragments.

Here is an example:

fragment ChildPackage on Package {
  qid # non-null field
  name
  address {
    qid
  }
}

And this is the query:

query Recipient {
	qid
	name
	packages {
		...ChildPackage 
		packages {
			...ChildPackage    
			packages {
				...ChildPackage    
				}
			}
		}
	}
}

In this particular example, we expect to get two items in the top level packages response, and then the follow up packages to be empty. However, what we get are in the top level packages is an array with two null values in it. However, when we expand fragment into the query like this:

query Recipient {
	qid
	name
	packages {
		qid # non-null field
		name
		address {
			qid
		}
		packages {
			...ChildPackage    
			packages {
				...ChildPackage    
				}
			}
		}
	}
}

Then we get the expected response, two Package entities with empty packages arrays returned in them.

Why is the response between a fragment and it's exact same fields different? Also, the double null response seems incorrect, maybe it is related to the null expansion issue in #80

Any thoughts?

[johnymontana]

@mvid Could you try these queries against the experimental endpoint http://localhost:7474/graphql/experimental/ and see if you have the same behavior?