While executing the following query
db.runCommand({ aggregate: "currentOp_cursor", pipeline: [{ $addFields: { newVal: {$function: {args: [], body: "sleep(1000000)", lang: "js"}}, bigDoc: createLargeDoc() } }], comment: TestData.comment, cursor: {} })
the "collection migration" can happen, which kills the query, resulting in no matching $currentOp objecting being returned.
In order to avoid this from happening, we need to mark this test as assumes_balancer_off