[TINKERPOP-1359] Exception thrown when calling subgraph() on Neo4jGraph

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.1.2-incubating
• Fix Version/s: 3.1.3, 3.2.1
• Component/s: neo4j
• Assignee: Stephen Mallette
• Reporter: Francesco Vivoli
• Created: 07/Jul/16 12:35
• Updated: 09/Jul/16 16:16
• Resolved: 08/Jul/16 20:38

Description

It seems calling subgraph() on a Neo4j database triggers an UnsupportedOperationException

This has been tested on gremlin-console-3.2.0-incubating.

Steps to reproduce
-------------------------

graph = Neo4jGraph.open('/tmp/test')
g = graph.traversal()
graph.cypher('create (p:Player {pid:1, site:10})')
graph.cypher('create (p:Player {pid:2, site:10})')
graph.cypher('create (p:Player {pid:3, site:10})')
graph.cypher('match (p:Player {pid:3}), (p2:Player {pid:2}) merge (p)-[:AKA {t:100}]-(p2)')
sg = g.V(2).outE().subgraph('sg').cap('sg').next()

Expected behaviour: subgraph is created
Actual behaviour: the following exception is thrown

java.lang.UnsupportedOperationException: Properties on a vertex property is not supported
	at org.apache.tinkerpop.gremlin.structure.VertexProperty$Exceptions.metaPropertiesNotSupported(VertexProperty.java:103)
	at org.apache.tinkerpop.gremlin.neo4j.structure.trait.NoMultiNoMetaNeo4jTrait.getProperties(NoMultiNoMetaNeo4jTrait.java:146)
	at org.apache.tinkerpop.gremlin.neo4j.structure.Neo4jVertexProperty.properties(Neo4jVertexProperty.java:97)
	at org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.SubgraphStep.lambda$getOrCreate$2(SubgraphStep.java:102)
	at org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.SubgraphStep$$Lambda$64/777687292.accept(Unknown Source)
	at java.util.Iterator.forEachRemaining(Iterator.java:116)
	at org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.SubgraphStep.getOrCreate(SubgraphStep.java:100)
	at org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.SubgraphStep.addEdgeToSubgraph(SubgraphStep.java:111)
	at org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.SubgraphStep.sideEffect(SubgraphStep.java:64)
	at org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.SideEffectStep.processNextStart(SideEffectStep.java:39)
	at org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep.hasNext(AbstractStep.java:140)
	at org.apache.tinkerpop.gremlin.process.traversal.step.util.ExpandableStepIterator.hasNext(ExpandableStepIterator.java:42)
	at org.apache.tinkerpop.gremlin.process.traversal.step.util.SupplyingBarrierStep.processAllStarts(SupplyingBarrierStep.java:83)
	at org.apache.tinkerpop.gremlin.process.traversal.step.util.SupplyingBarrierStep.processNextStart(SupplyingBarrierStep.java:70)
	at org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep.next(AbstractStep.java:126)
	at org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep.next(AbstractStep.java:37)
	at org.apache.tinkerpop.gremlin.process.traversal.util.DefaultTraversal.next(DefaultTraversal.java:156)