public function testUpdatesIndexLength()
{
    $this->connection->exec('CREATE TABLE index_length (path text NULL)');
    $this->connection->exec('CREATE INDEX path ON index_length (path(333))');

    $table = new Table('index_length');
    $table->addColumn('path', 'text', ['notnull' => false]);
    $table->addIndex(['path'], 'path', [], ['lengths' => [768]]);

    $fromSchema = $this->connection->getSchemaManager()->createSchema();
    $toSchema = new Schema([$table]);

    $diff = $fromSchema->getMigrateToSql($toSchema, $this->connection->getDatabasePlatform());

    self::assertContains('ALTER TABLE index_length DROP INDEX path, ADD INDEX path (path(768))', $diff);
}