[TINKERPOP-2674] `as('a')` step followed by `select('a')` not behaving as expected

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Not A Problem
• Affects Version/s: 3.5.1
• Component/s: tinkergraph
• Assignee: Unassigned
• Reporter: Fredrick Eisele
• Created: 23/Dec/21 21:23
• Updated: 30/Dec/21 18:51
• Resolved: 30/Dec/21 18:51

Description

The inclusion of the `select()` step changes the result when it should not.

Steps to replicate.
Given a graph:

g.addV('[avm]Design').as('root').
        property('VertexLabel','[avm]Design').
        property('uuid','SRC_UUID').
        property('[]Name', 'Axe').
        addV('[]RootContainer').as('rc').
        property('VertexLabel','[]RootContainer').
        property('[]Name','Axe').
        addV('[]Property').as('p1').
        property('VertexLabel','[]Property').
        property('[]XPosition','56').
        addV('[]Value').as('v1').
        property('VertexLabel','[]Value').
        property('[]stuff','12').
        addV('[]Property').as('p2').
        property('VertexLabel','[]Property').
        property('[]XPosition','80').
        addV('[]Value').as('v2').
        property('VertexLabel','[]Value').
        property('[]stuff','90').
        addE('inside').from('rc').to('root').
        addE('inside').from('p1').to('rc').
        addE('inside').from('v1').to('p1').
        addE('inside').from('p2').to('rc').
        addE('inside').from('v2').to('p2').
        iterate()

The following two queries incorrectly produce different results.
This first query produces a list of all the vertices with the exception of 'r0'.

g.V().
  has('[avm]Design', 'uuid', 'SRC_UUID').as('r0').
  repeat(__.in('inside').simplePath()).
    emit().
    until(__.in('inside').count().is(0)).
  toList()

The addition of the `select('r0')` step in this query causes no vertices to be returned.

g.V().
  has('[avm]Design', 'uuid', 'SRC_UUID').as('r0').
  select('r0').
  repeat(__.in('inside').simplePath()).
    emit().
    until(__.in('inside').count().is(0)).
  toList()