'use strict';

/**
 * agg_sort_external.js
 *
 * Runs an aggregation with a $match that returns half the documents followed
 * by a $sort on a field containing a random float.
 *
 * The data returned by the $match is greater than 100MB, which should force an external sort.
 */
load('jstests/concurrency/fsm_libs/extend_workload.js');  // for extendWorkload
load('jstests/concurrency/fsm_workloads/agg_base.js');    // for $config

var $config = extendWorkload($config, function($config, $super) {
    // use enough docs to exceed 100MB, the in-memory limit for $sort and $group
    $config.data.numDocs = 24 * 1000;
    var MB = 1024 * 1024;  // bytes
    // assert that *half* the docs exceed the in-memory limit, because the $match stage will
    // only
    // pass half the docs in the collection on to the $sort stage.
    assertAlways.lte(100 * MB, $config.data.numDocs * $config.data.docSize / 2);

    $config.data.getOutputCollPrefix = function getOutputCollPrefix(collName) {
        return collName + '_out_agg_sort_external_';
    };

    $config.states.query = function query(db, collName) {
        var otherCollName = this.getOutputCollPrefix(collName) + this.tid;
        var cursor = db[collName].aggregate(
            [{$match: {flag: true}}, {$sort: {rand: 1}}, {$out: otherCollName}],
            {allowDiskUse: true});
        assertAlways.eq(0, cursor.itcount());
        assertWhenOwnColl.eq(db[collName].find().itcount() / 2, db[otherCollName].find().itcount());
    };

    return $config;
});