/**
 * Long index namespaces exceeding 127 characters are supported starting in 4.2.
 * However, we should still disallow long index namespaces under FCV 4.0.
 * TODO: remove this test in 4.4.
 */
(function() {
    'use strict';

    TestData.replSetFeatureCompatibilityVersion = '4.0';
    const rst = new ReplSetTest({
        nodes: [
            {binVersion: 'latest'},
            {rsConfig: {priority: 0, votes: 0}},
        ]
    });
    rst.startSet();
    rst.initiate();
    rst.restart(1, {binVersion: '4.0'});

    const primary = rst.getPrimary();
    const mydb = primary.getDB('test');
    const coll = mydb.getCollection('long_index_name');

    // Compute maximum index name length for this collection under FCV 4.0.
    const maxNsLength = 127;
    const maxIndexNameLength = maxNsLength - (coll.getFullName() + ".$").length;
    jsTestLog('Max index name length under FCV 4.0 = ' + maxIndexNameLength);

    // Create an index with the longest name allowed for this collection.
    assert.commandWorked(coll.createIndex({a: 1}, {name: 'a'.repeat(maxIndexNameLength)}));

    // If this command succeeds unexpectedly, it will cause an fassert on the 4.0 secondary which
    // cannot handle long index namespaces, with a "CannotCreateIndex: ... index name ... too long"
    // error message.
    assert.commandFailedWithCode(
        coll.createIndex({b: 1}, {name: 'b'.repeat(maxIndexNameLength + 1)}),
        ErrorCodes.CannotCreateIndex);

    // The existing index on {x: 1} has an index name that is the longest supported under FCV 4.0
    // for the current collection name.
    // Any attempt to rename this collection with a longer name must fail. Otherwise, the invalid
    // index namespace will cause the 4.0 secondary to fassert.
    assert.commandFailedWithCode(coll.renameCollection(coll.getName() + 'z'),
                                 ErrorCodes.InvalidLength);

    rst.stopSet();
})();