lenskit.batch.TestRequestAdapter
================================

.. py:class:: lenskit.batch.TestRequestAdapter(lists, *, items_as = 'test')
   :canonical: lenskit.batch._queries.TestRequestAdapter

   Bases: :py:obj:`collections.abc.Iterable`\ [\ :py:obj:`BatchRecRequest`\ ], :py:obj:`collections.abc.Sized`


   Wrapper for an item list collection that interprets it as a collection of
   test requests.  Iterating over this collection will yield the requests in
   the same order they are in the underlying item list collection.

   The ``user_id`` and ``query_id`` key fields, if present are used to
   construct the recommendation queries.  If there is no ``query_id`` field,
   then the entire key is used as a query ID.  The item lists themselves are
   interpreted as  directed by the ``items_as`` option:

   ``test``
       Items are used as test items (e.g., the items for which to predict
       ratings), but **not** candidates.

   ``candidates``
       Items are used as candidate lists.

   ``both``
       Items are used as both test items and candidates.

   ``None``
       Items are excluded.

   .. seealso::

       :ref:`batch-queries`, :class:`~lenskit.batch.BatchRecRequest`

   :param lists: The item list collection.
   :param items_as: Where to put the item lists in the request.

   :Warns: **DataWarning** -- If the item list collection cannot be used to construct usable
           requests.

   :Stability: Caller


   .. py:attribute:: lists
      :type:  lenskit.data.ItemListCollection


   .. py:attribute:: item_use
      :type:  Literal['test', 'candidates', 'both'] | None


   .. py:method:: __len__()


   .. py:method:: __iter__()