Problem Description

A valid aggregation pipeline generates the error $eq cannot be top-level" when an attempt is made to export to java

Steps to Reproduce

The following test pipeline demonstrates the problem:[{$addFields: {
"elemZero":

{ $arrayElemAt: ["$LOANMI", 0] }

,
"elemOne":

{ $arrayElemAt: ["$LOANMI", 1] }

}}, {$group: {
_id: null,
"MICancellation": {
$push: {
$cond: {
if: {
$and: [{
"$eq": [

{ $ifNull: ["$elemZero", "unspecified"] }

, "unspecified"]
},
{
"$eq": [

{ $type: "$elemOne" }

, "date"]
}
]
},
then: "$_id",
else: null
}
}
}
}}]

Expected Results

Java code generated

Actual Results

Error message $eq cannot be top-level" is generated.

 

Additional Notes

Reported by Customer Freddie Mac