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// This test ensuexplain an explain of an aggregate through mongos has the intended format.
(function() {
"use strict";
load('jstests/libs/analyze_plan.js'); // For planHasStage.
const st = new ShardingTest({shards: 2});
const mongosDB = st.s.getDB("test");
const coll = mongosDB.agg_explain_fmt;
// Insert documents with {_id: -5} to {_id: 4}.
assert.commandWorked(coll.insert(Array.from({length: 10}, (_, i) => ({_id: i - 5}))));
// Test that with an unsharded collection we don't get any kind of 'splitPipeline', just the
// normal explain with 'stages'.
let explain = coll.explain().aggregate([{$project: {a: 1}}]);
assert(!explain.hasOwnProperty("splitPipeline"), explain);
assert(explain.hasOwnProperty("stages"), explain);
// Now shard the collection by _id and move a chunk to each shard.
st.shardColl(coll, {_id: 1}, {_id: 0}, {_id: 0});
// Test that we now have a split pipeline with information about what pipeline ran on each
// shard.
explain = coll.explain().aggregate([{$project: {a: 1}}]);
assert(explain.hasOwnProperty("splitPipeline"), explain);
assert(explain.splitPipeline.hasOwnProperty("shardsPart"), explain.splitPipeline);
assert(explain.splitPipeline.hasOwnProperty("mergerPart"), explain.splitPipeline);
assert(explain.hasOwnProperty("shards"), explain);
for (let shardId in explain.shards) {
const shardExplain = explain.shards[shardId];
assert(shardExplain.hasOwnProperty("host"), shardExplain);
assert(shardExplain.hasOwnProperty("stages"), shardExplain);
}
// Do a sharded explain from a mongod, not mongos, to ensure that it does not have a
// SHARDING_FILTER stage.");
const shardDB = st.shard0.getDB(mongosDB.getName());
explain = shardDB[coll.getName()].explain().aggregate([{$match: {}}]);
assert(!planHasStage(
shardDB, explain.stages[0].$cursor.queryPlanner.winningPlan, "SHARDING_FILTER"),
explain);
st.stop();
}());
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