function collectReferenceIds(node, referenceIds) {
      const variable = findVariable(utils.getScope(context, node), node)
      if (!variable) {
        return
      }
      for (const reference of variable.references) {
        referenceIds.add(reference.identifier)
      }
    }
Collect identifier id
@param {Identifier} node
@param {Set<Identifier>} referenceIds