(function() {
    "use strict";

    const replTest = new ReplSetTest({
        nodes: 3,
    });

    replTest.startSet();
    replTest.initiate();

    let primary = replTest.getPrimary();
    const insertColl = primary.getDB("test").foo;
    for (let i = 0; i < 500; ++i) {
        insertColl.insert({a: i, string: "test test test"});
    }

    let secondary = replTest.getSecondary();
    secondary.adminCommand({setParameter: 1, internalQuerySlotBasedExecutionHashAggApproxMemoryUseInBytesBeforeSpill: 1});

    let readColl = secondary.getDB("test").foo;

    const pipeline = [{$group: {_id: '$a', s: {$addToSet: '$string'}, p: {$push: '$a'}}}];
    
    let res = readColl.aggregate(pipeline, {allowDiskUse: true,
                                            readConcern: {level: "majority"},
                                            writeConcern:{"w": "majority"}
                                           }).toArray();

    // Never reached.
    replTest.stopSet();
})();