* @see org.springframework.data.mongodb.core.aggregation.SpelExpressionTransformer.SpelNodeWrapper#convertSpelNodeToMongoObjectExpression(org.springframework.data.mongodb.core.aggregation.SpelExpressionTransformer.ExpressionConversionContext)
*/
@Override
protected Object convert(AggregationExpressionTransformationContext<OperatorNode> context) {
OperatorNode currentNode = context.getCurrentNode();
DBObject operationObject = createOperationObjectAndAddToPreviousArgumentsIfNecessary(context, currentNode);
Object leftResult = transform(currentNode.getLeft(), currentNode, operationObject, context);
if (currentNode.isUnaryMinus()) {
return convertUnaryMinusOp(context, leftResult);
}
// we deliberately ignore the RHS result
transform(currentNode.getRight(), currentNode, operationObject, context);
return operationObject;
}