Query with sort ($natural:1) is reported as indexOnly when it should not be

var coll = db.getCollection("covered_negative_1") coll.drop() for (i=0;i<100;i++) { coll.insert( {a:i, b:"strvar_"+(i%13), c:NumberInt(i%10), d: i*10, e: [i, i%10]} ) } coll.insert coll.ensureIndex( {a:1,b:-1,c:1} ) coll.ensureIndex( {e:1} ) coll.ensureIndex( {d:1} ) // Test projection and $natural sort var plan = coll.find({a:{$gt:70}}, {a:1, b:1, c:1, _id:0} ).sort({$natural:1}).hint( {a:1, b:-1, c:1} ).explain() assert.eq(false, plan.indexOnly, "negative.1.5 - indexOnly should be false on a non covered query")