Calling first() on NodeSet causes future calls on .all() to be filtered

[gs00cut]

Hi,

I am running neomodel 4.0.1.

I have implemented a method that performs simple ordering on node set based on 2 integer properties MajorVersion/MinorVersion. I simply do a test on first node to see if nodes well have these properties and then do the ordering (see below).

I made some tests and noticed strange behaviours between theNodeSetobject and the expanded list for the same NodeSet when calling the .all() method.

Behaviour 1
Calling .first() method on NodeSet causes later calls to .all() to be filtered on the first node of the nodeset:

As you can see, calling .all() after the check on the first item in nodeset returns a list of 1 item while the nodeset contains 6 as expected.

Behaviour 2
As a workaround, I thought avoiding calling .first() method would do the trick but I noticed that once .all() is called, the order_by method no longer works on the nodeset:

As you can see in debug console, the languages are not sorted ascendingly by MajorVersion (version can be seen in field slug_languageid) as it should be.

I finally ended up with this workaround working well:

    @staticmethod
    def order_by_version(nodes: List[NodeEntity]) -> List[NodeEntity]:
        """Order nodeset set by descending version.

        Nodes in the node set must have MajorVersion and MinorVersion attributes.
        """
        if (
            not hasattr(nodes[0], "MajorVersion")
            or not hasattr(nodes[0], "MinorVersion")
        ):
            raise AttributeError("Attributes 'MajorVersion'/'MinorVersion' not defined.")

        nodes = sorted(nodes, key=lambda x: (-x.MajorVersion, -x.MinorVersion))
        return nodes

However I have the feeling that something is not working as expected regarding usage of nodeset / nodeset.all().

Thanks,

Gilles

[AntonLydike]

Hi Gilles, can you provide a small, self-contained test case so that we can better understand the issue and fix it?

[gs00cut]

Hi,

Sorry for the late answer. Thanks for looking at the issue.

Basically the scenario to reproduce the problem is quite basic:

For the first observation:

1. Populate a NodeSet nodeset object of length > 1 (no matter the type of nodes in it)
2. Call the method nodeset.first()
3. Call the method nodeset.all() => you don't get a list of all nodes, but only a list containing the first node

For the second observation:

1. Populate a NodeSet nodeset object of length > 1 (no matter the type of nodes in it)
2. Call the method nodeset.all()
3. Then call the method nodeset.order_by("YOUR_PROPERTY").all() (you can order by any property you have defined on your nodes) => the list of nodes is not ordered as expected