// Cannot implicitly shard accessed collections because of following errmsg: Cannot output to a
// non-sharded collection because sharded collection exists already.
// @tags: [
//   assumes_unsharded_collection,
//   # mapReduce does not support afterClusterTime.
//   does_not_support_causal_consistency,
//   does_not_support_stepdowns,
// ]

/**
 * Test that the server returns an error response for map-reduce operations that attempt to insert a
 * document larger than 16MB as a result of the reduce() or finalize() functions and using the
 * "replace" action for the out collection.
 */
(function() {
function mapper() {
    // Emit multiple values to ensure that the reducer gets called.
    emit(this._id, 1);
    emit(this._id, 1);
}

function createBigDocument() {
    // Returns a document of the form { _id: ObjectId(...), value: '...' } with the specified
    // 'targetSize' in bytes.
    function makeDocWithSize(targetSize) {
        var doc = {_id: new ObjectId(), value: ''};

        var size = Object.bsonsize(doc);
        assert.gte(targetSize, size);

        // Set 'value' as a string with enough characters to make the whole document 'size'
        // bytes long.
        doc.value = new Array(targetSize - size + 1).join('x');
        assert.eq(targetSize, Object.bsonsize(doc));

        return doc;
    }

    var maxDocSize = 16 * 1024 * 1024;
    return makeDocWithSize(maxDocSize + 1).value;
}

function runTest(testOptions) {
    db.input.drop();
    db.mr_bigobject_replace.drop();

    // Insert a document so the mapper gets run.
    assert.writeOK(db.input.insert({}));

    var res = db.runCommand(Object.extend({
        mapReduce: "input",
        map: mapper,
        out: {replace: "mr_bigobject_replace"},
    },
                                          testOptions));

    assert.commandFailed(res, "creating a document larger than 16MB didn't fail");
    assert.lte(0,
               res.errmsg.indexOf("object to insert too large"),
               "map-reduce command failed for a reason other than inserting a large document");
}

runTest({reduce: createBigDocument});
runTest({
    reduce: function() {
        return 1;
    },
    finalize: createBigDocument
});
})();