Cannot set indexes

[OKNoah]

This code does not seem to work as intended:

static async _getCollection () {
    if (this._collection) {  // always seems to be true
      return this._collection
    }

    const db = await this._getDatabase()
    const collection = db.collection(this.name)
    try {
      await collection.create()
      await this._setIndexes(collection)
    } catch (e) {
    }
    return this._collection = collection
  }

  static async _setIndexes (collection) {
    const schema = this._getSchema()
    for (const field of schema) {
      if (!field.options.index) continue

      const path = field.path.join('.')
      const unique = field.options.unique
      await collection.createHashIndex(path, {unique})
    }
  }