$multiply operator may return with or w/o an error depending on whether pipeline optimisation is enabled

db.col.insert({num: Infinity})

db.col.aggregate({$project: {a: {$multiply: [NumberDecimal(1), "$num"]}}})

2019-08-09T11:32:49.176+0100 E  QUERY    [js] Error: command failed: {

        "ok" : 0,

        "errmsg" : "Can't coerce out of range value inf to long",

        "code" : 31109,

        "codeName" : "Location31109"

}

db.adminCommand({configureFailPoint: 'disablePipelineOptimization', mode: 'alwaysOn'})

db.col.aggregate({$project: {a: {$multiply: [NumberDecimal(1), "$num"]}}})

{ "_id" : ObjectId("5d4d4ba7bf418d2f35ef7d3c"), "a" : NumberDecimal("Infinity") }