Cypher: nodes(), relationships(), length() on variable-length path patterns (e.g. [*1..3]) not implemented #4353

Context

Reported by a user migrating from Neo4j in the blog post Moving a Graph RAG system from Neo4j to ArcadeDB (May 2026, against ArcadeDB 26.4.1-SNAPSHOT). The author concluded that variable-length path queries were unreliable and recommended using fixed-hop patterns instead.

Problem

nodes(path), relationships(path), and length(path) are not supported when path is bound from a variable-length pattern such as [*1..3] or [*2].

This is acknowledged in the test suite: three tests in OpenCypherAdvancedFunctionTest.java are marked @Disabled with the reason "Requires path matching with variable length relationships to be fully implemented":

• nodesFunction()
• relationshipsFunction()
• lengthFunctionOnPath()

(all using [*2] patterns).

Reproduction

MATCH p = (a:Worker)-[*1..3]->(b:Worker)
RETURN nodes(p), relationships(p), length(p)

Expected: list of nodes/relationships/length per matching path.
Actual: errors or missing rows (per the disabled tests).

Why it matters

Variable-length traversal is a primary reason users adopt a graph database. Without these accessors, downstream queries that depend on path inspection (e.g. RAG over multi-hop relationships) need to be rewritten as fixed-hop joins, which is exactly what the blog author resorted to.

Suggested fix

Plumb the variable-length traversal result through to a Path object that supports nodes/relationships/length, and re-enable the disabled tests. Several recent fixes already touched this area (#4006, #3999, #4190, #4111, #3997) — this issue tracks the remaining accessor coverage.