In 5.26.3, apoc.paths.toJsonTree does not correctly map full path to tree

[rossoneri8]

Expected Behavior (Mandatory)

Expected response, currently coming back from apoc.convert.toTree. Note the inclusion of path C->D->E in tree

{
  "_type": "Node",
  "_id": 4357,
  "rels": [
    {
      "_type": "Node",
      "rels._id": 47200,
      "_id": 4358,
      "rels": [
        {
          "_type": "Node",
          "rels._id": 47202,
          "_id": 4360,
          "rels": [
            {
              "_type": "Node",
              "rels._id": 47204,
              "_id": 4361,
              "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47204",
              "name": "E",
              "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4361"
            }
          ],
          "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47202",
          "name": "D",
          "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4360"
        }
      ],
      "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47200",
      "name": "B",
      "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4358"
    },
    {
      "_type": "Node",
      "rels._id": 47201,
      "_id": 4359,
      "rels": [
        {
          "_type": "Node",
          "rels._id": 47203,
          "_id": 4360,
          "rels": [
            {
              "_type": "Node",
              "rels._id": 47204,
              "_id": 4361,
              "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47204",
              "name": "E",
              "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4361"
            }
          ],
          "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47203",
          "name": "D",
          "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4360"
        }
      ],
      "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47201",
      "name": "C",
      "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4359"
    }
  ],
  "name": "A",
  "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4357"
}

Actual Behavior (Mandatory)

Unexpected response, currently coming back from apoc.paths.toJsonTree. Note the exclusion of path C->D->E in tree

{
  "_type": "Node",
  "_id": 4357,
  "rels": [
    {
      "_type": "Node",
      "rels._id": 47200,
      "_id": 4358,
      "rels": [
        {
          "_type": "Node",
          "rels._id": 47202,
          "_id": 4360,
          "rels": [
            {
              "_type": "Node",
              "rels._id": 47204,
              "_id": 4361,
              "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47204",
              "name": "E",
              "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4361"
            }
          ],
          "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47202",
          "name": "D",
          "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4360"
        }
      ],
      "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47200",
      "name": "B",
      "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4358"
    },
    {
      "_type": "Node",
      "rels._id": 47201,
      "_id": 4359,
      "rels": [
        {
          "_type": "Node",
          "rels._id": 47203,
          "_id": 4360,
          "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47203",
          "name": "D",
          "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4360"
        }
      ],
      "rels._elementId": "5:e3ade55d-9ea1-48cf-b308-75e756f0f38d:47201",
      "name": "C",
      "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4359"
    }
  ],
  "name": "A",
  "_elementId": "4:e3ade55d-9ea1-48cf-b308-75e756f0f38d:4357"
}

How to Reproduce the Problem

Follow steps outlined in Steps, i.e. create the simple dataset and then query it using the following query utilizing apoc.paths.toJsonTree

MATCH path=((:Node)-[:RELS]->(:Node)-[:RELS]->(:Node)-[:RELS]->(:Node))
WITH collect(path) as paths
CALL apoc.paths.toJsonTree(paths, true) YIELD value
RETURN value as tree

Simple Dataset (where it's possibile)

MERGE (a:Node {name:'A'}) 
MERGE (b:Node {name:'B'}) 
MERGE (c:Node {name:'C'}) 
MERGE (d:Node {name:'D'}) 
MERGE (e:Node {name:'E'}) 

MERGE (a)-[:RELS]->(b)
MERGE (a)-[:RELS]->(c)
MERGE (b)-[:RELS]->(d)
MERGE (c)-[:RELS]->(d)
MERGE (d)-[:RELS]->(e)

Steps (Mandatory)

1. Create DB to match initial state
2. Run the following query and note the lack of relationship from nodes C->D->E in tree

MATCH path=((:Node)-[:RELS]->(:Node)-[:RELS]->(:Node)-[:RELS]->(:Node))
WITH collect(path) as paths
CALL apoc.paths.toJsonTree(paths, true) YIELD value
RETURN value as tree

3. Run the following deprecated query and note the inclusion of nodes C->D->E in tree

MATCH path=((:Node)-[:RELS]->(:Node)-[:RELS]->(:Node)-[:RELS]->(:Node))
WITH collect(path) as paths
CALL apoc.convert.toTree(paths, true) YIELD value
RETURN value as tree

Screenshots (where it's possibile)

Specifications (Mandatory)

Currently used versions

Versions

• OS: docker, neo4j:5.26.3
• Neo4j: 5.26.3
• Neo4j-Apoc: 5.26.3

[hvub]

Thank you for your message.

apoc.convert.toTree was deprecated because its implementation had various issues in how it handles directionality, loops and other things not immediately suitable for tree representation.

apoc.paths.toJsonTree is the replacement, but as the documentation points out with a different behavior. apoc.paths.toJsonTree traverses the relationships it finds in the paths only in forward direction and it stop to expand the tree when it encounters a node it has seen before.

So, I am afraid to say that the behavior you are observing is intentional.