OctoberCMS不会创建索引

I am creating some database tables in my OctoberCMS plugin, and in these tables I want to use some indexes. The problem is that these indexes don't get created, de tables get created without the indexes.

Schema::create('table', function ($table) {
        $table->engine = 'InnoDB';
        $table->increments('id');
        $table->text('textField')->index();
        $table->timestamps();
    });

Why this is/could be?

EDIT: In light of a comment I want to mention that this is not just occurring on text fields but also on integer fields.

Try in this way:

Schema::create('table', function ($table) {
    $table->engine = 'InnoDB';
    $table->increments('id');
    $table->text('textField');
    $table->index(['text_field'])
    $table->timestamps();
});