The $group processing code setup expects that any ExpressionObject will not have any children. It could probably handle this case without asserting, or we could fix the parsing of {$expr: {}} to avoid producing an ExpressionObject.
- is caused by
-
SERVER-66248 Projection with ExpressionObject does not round trip (serialize + parse)
- Closed
- related to
-
SERVER-89729 Add more test cases for the combination of $group + $expr
- Closed