Merge 4eed8e2d60 into dd10cb8e9a

docs/topics/loaders.rst

@@ -34,7 +34,8 @@ Item Loader ``__init__`` method using the :ref:`item <topics-items>` class
 specified in the :attr:`ItemLoader.default_item_class` attribute.
 
 Then, you start collecting values into the Item Loader, typically using
-:ref:`Selectors <topics-selectors>`. You can add more than one value to
+:ref:`Selectors <topics-selectors>`. To note, the Item Loader will extract data
+by using the selector ``.getall()`` method. You can add more than one value to
 the same item field; the Item Loader will know how to "join" those values later
 using a proper processing function.
 
@@ -77,7 +78,11 @@ data that will be assigned to the ``name`` field later.
 Afterwards, similar calls are used for ``price`` and ``stock`` fields
 (the latter using a CSS selector with the :meth:`~ItemLoader.add_css` method),
 and finally the ``last_update`` field is populated directly with a literal value
-(``today``) using a different method: :meth:`~ItemLoader.add_value`.
+(``today``) using a different method: :meth:`~ItemLoader.add_value`. To note 
+:meth:`~ItemLoader.add_css` and :meth:`~ItemLoader.add_xpath` methods will always
+return a list as they are actually calling selector ``getall()`` method over 
+``get()`` which may return a string value. Thus, input processors should be 
+implemented by waiting for a list instead of a single string.
 
 Finally, when all data is collected, the :meth:`ItemLoader.load_item` method is
 called which actually returns the item populated with the data