[BUG] labelFilter for subgraph_all doesn't work as documented

[thomas-tran-de]

Describe the bug
In the documentation, examples for subgraph_all are given. Unfortunately, they don't work as described.

To Reproduce
Run the following query:

CREATE (w:Wolf)-[ca:CATCHES]->(d:Dog), (c:Cat), (m:Mouse), (h:Human);
MATCH (w:Wolf), (d:Dog), (c:Cat), (m:Mouse), (h:Human)
WITH w, d, c, m, h
CREATE (d)-[:CATCHES]->(c)
CREATE (c)-[:CATCHES]->(m)
CREATE (d)-[:FRIENDS_WITH]->(m)
CREATE (h)-[:OWNS]->(d)
CREATE (h)-[:HUNTS]->(w)
CREATE (h)-[:HATES]->(m);
MATCH (dog:Dog)
CALL path.subgraph_all(dog, {
    labelFilter: ["/Mouse"]
})
YIELD nodes AS nodes, rels AS rels
RETURN nodes, rels

This returns only a single node, Mouse:

{
  "nodes": [
    { "id": 13, "labels": ["Mouse"], "properties": {}, "type": "node" }
  ],
  "rels": []
}

Expected behavior
According to the documentation, this filtering will return 3 paths: Dog->Cat->Mouse, Dog<-Human->Mouse, Dog->Mouse.

Additional context
I tried this in the newest Memgraph version 3.2.1.

[katarinasupe]

Thank you @thomas-tran-de for reporting the issue. I managed to reproduce it and can confirm that the same behavior happens to me as well, and it is opposite to what's described.

Are you blocked by this currently?

[thomas-tran-de]

Thanks for the quick reply @katarinasupe. No, I'm not blocked by this. I came up with a workaround for my specific use case which isn't as elegant but leads to the same result. I'll switch back to my initial idea when path.subgraph_all is fixed.

[thomas-tran-de]

Hi @katarinasupe, this just got more important to me.

I went through the label filter examples in the documentation and none of them work.

Could the issue be AreLabelsValid (Link)? It looks too restrictive. Whenever a termination or end node is used, only those will be returned. This can be illustrated by specifying all intermediate nodes as end nodes:

Starting Node	Label Filter	Paths Returned	Paths Expected	Workaround Filter
Dog	["/Mouse"]	Mouse	Dog->Cat->Mouse, Dog<-Human->Mouse, Dog->Mouse	[">Dog", "/Mouse", ">Cat", ">Human"]
Dog	["/Mouse", "Cat"]	None	Dog->Mouse, Dog->Cat->Mouse	[">Dog", "/Mouse", ">Cat"]
Dog	["/Mouse", "-Cat", "-Human"]	Mouse	Dog->Mouse	[">Dog", "/Mouse"]
Cat	[">Dog", "+Human", "+Wolf"]	None	Cat<-Dog, Cat<-Dog<-Human->Wolf->Dog	[">Cat", ">Dog", ">Human", ">Wolf"]

Maybe !config_.label_bools_status.termination_activated && !config_.label_bools_status.end_node_activated && Whitelisted(label_bools.whitelisted) just needs to be replaced with Whitelisted(label_bools.whitelisted)? As a user, I expect the whitelist to work independent of termination and end nodes.