fix: needs(field-data); XBlock-like; etc

xblock/core.py

@@ -34,7 +34,7 @@
 ])
 
 # __all__ controls what classes end up in the docs.
-__all__ = ['Blocklike', 'XBlock', 'XBlockAside']
+__all__ = ['XBlock', 'XBlockAside']
 
 UNSET = object()
 
@@ -98,24 +98,24 @@ class Blocklike(metaclass=_AutoNamedFieldsMetaclass):
     @classmethod
     def get_resources_dir(cls):
         """
-        Gets the resource directory for this Blocklike.
+        Gets the resource directory for this XBlock-like class.
         """
         return cls.resources_dir
 
     @classmethod
     def get_public_dir(cls):
         """
-        Gets the public directory for this Blocklike.
+        Gets the public directory for this XBlock-like class.
         """
         return cls.public_dir
 
     @classmethod
     def get_i18n_js_namespace(cls):
         """
-        Gets the JavaScript translations namespace for this Blocklike.
+        Gets the JavaScript translations namespace for this XBlock-like class.
 
         Returns:
-            str: The JavaScript namespace for this Blocklike.
+            str: The JavaScript namespace for this XBlock-like class.
             None: If this doesn't have JavaScript translations configured.
         """
         return cls.i18n_js_namespace
@@ -128,13 +128,13 @@ def open_local_resource(cls, uri):
         The container calls this method when it receives a request for a
         resource on a URL which was generated by Runtime.local_resource_url().
         It will pass the URI from the original call to local_resource_url()
-        back to this method. The Blocklike must parse this URI and return an open
+        back to this method. The XBlock-like must parse this URI and return an open
         file-like object for the resource.
 
         For security reasons, the default implementation will return only a
         very restricted set of file types, which must be located in a folder
         that defaults to "public".  The location used for public resources can
-        be changed on a per-Blocklike basis. Blocklike authors who want to override
+        be changed on a per-XBlock-like basis. XBlock-like authors who want to override
         this behavior will need to take care to ensure that the method only
         serves legitimate public resources. At the least, the URI should be
         matched against a whitelist regex to ensure that you do not serve an
@@ -210,7 +210,7 @@ def handler(cls, func):
     @classmethod
     def needs(cls, *service_names):
         """
-        A class decorator to indicate that a Blocklike class needs particular services.
+        A class decorator to indicate that an XBlock-like class needs particular services.
         """
         def _decorator(cls_):
             for service_name in service_names:
@@ -221,7 +221,7 @@ def _decorator(cls_):
     @classmethod
     def wants(cls, *service_names):
         """
-        A class decorator to indicate that a Blocklike class wants particular services.
+        A class decorator to indicate that a XBlock-like class wants particular services.
         """
         def _decorator(cls_):
             for service_name in service_names:
@@ -234,7 +234,7 @@ def service_declaration(cls, service_name):
         """
         Find and return a service declaration.
 
-        Blocklikes declare their service requirements with `@XBlock{Aside}.needs` and
+        XBlock-like classes declare their service requirements with `@XBlock{Aside}.needs` and
         `@XBlock{Aside}.wants` decorators.  These store information on the class.
         This function finds those declarations for a block.
 
@@ -251,7 +251,7 @@ def _services_requested(cls):  # pylint: disable=no-self-argument
         """
         A per-class dictionary to store the services requested by a particular XBlock.
         """
-        return {"field-data": "needs"}  # All Blocklikes needs field data
+        return {}
 
     @class_lazy
     def _combined_services(cls):  # pylint: disable=no-self-argument
@@ -305,7 +305,7 @@ def _set_field_if_present(cls, block, name, value, attrs):
             else:
                 setattr(block, name, value)
         else:
-            logging.warning("Blocklike %s does not contain field %s", type(block), name)
+            logging.warning("%s does not contain field %s", type(block), name)
 
     def __init__(self, runtime, scope_ids, field_data=None, **kwargs):
         """
@@ -317,7 +317,7 @@ def __init__(self, runtime, scope_ids, field_data=None, **kwargs):
             scope_ids (:class:`.ScopeIds`): Identifiers needed to resolve
                 scopes.
 
-            field_data (:class:`.FieldData`): Interface used by Blocklike's
+            field_data (:class:`.FieldData`): Interface used by XBlock-likes'
                 fields to access their data from wherever it is persisted.
                 DEPRECATED--supply a field-data Runtime service instead.
         """
@@ -369,7 +369,7 @@ def __repr__(self):
     @property
     def usage_key(self):
         """
-        A key identifying this particular usage of the Blocklike, unique across all learning contexts in the system.
+        A key identifying this particular usage of the XBlock-like, unique across all learning contexts in the system.
 
         Equivalent to to `.scope_ids.usage_id`.
         """
@@ -378,7 +378,7 @@ def usage_key(self):
     @property
     def context_key(self):
         """
-        A key identifying the learning context (course, library, etc.) that contains this Blocklike usage.
+        A key identifying the learning context (course, library, etc.) that contains this XBlock-like usage.
 
         Equivalent to `.scope_ids.usage_id.context_key`.
 
@@ -607,6 +607,7 @@ def __new__(mcs, name, bases, attrs):
         return super().__new__(mcs, name, bases, attrs)
 
 
+@Blocklike.needs("field-data")
 class XBlock(Plugin, Blocklike, metaclass=_HasChildrenMetaclass):
     """
     Base class for XBlocks. Derive from this class to create new type of XBlock.
@@ -732,8 +733,8 @@ def __init__(
         self,
         runtime,
         field_data=None,
-        *args,  # pylint: disable=keyword-arg-before-vararg
         scope_ids=UNSET,
+        *args,  # pylint: disable=keyword-arg-before-vararg
         **kwargs
     ):
         """
@@ -891,6 +892,7 @@ def has_support(self, view, functionality):
         return hasattr(view, "_supports") and functionality in view._supports  # pylint: disable=protected-access
 
 
+@Blocklike.needs("field-data")
 class XBlockAside(Plugin, Blocklike):
     """
     Base class for XBlock-like objects that are rendered alongside :class:`.XBlock` views.

xblock/test/test_core.py

@@ -385,6 +385,7 @@ def to_json(self, value):
             """Convert a datetime object to a string"""
             return value.strftime("%m/%d/%Y")
 
+    @Blocklike.needs("field-data")
     class FieldTester(Blocklike):
         """Toy class for field access testing"""
 
@@ -434,8 +435,9 @@ class FieldTester(XBlock):
 
 def test_object_identity():
     # Check that values that are modified are what is returned
+    @Blocklike.needs("field-data")
     class FieldTester(Blocklike):
-        """Toy class for ModelMetaclass and field access testing"""
+        """Toy class for field access testing"""
         field_a = List(scope=Scope.settings)
 
     def mock_default(block, name):
@@ -474,8 +476,9 @@ def mock_default(block, name):
 
 def test_caching_is_per_instance():
     # Test that values cached for one instance do not appear on another
+    @Blocklike.needs("field-data")
     class FieldTester(Blocklike):
-        """Toy class for ModelMetaclass and field access testing"""
+        """Toy class for field access testing"""
         field_a = List(scope=Scope.settings)
 
     field_data = MagicMock(spec=FieldData)
@@ -776,10 +779,13 @@ def test_handle_shortcut():
 
 
 def test_services_decorators():
-    # A default XBlock has requested no services
-    xblock = XBlock(None, None, None)
-    assert not XBlock._services_requested
-    assert not xblock._services_requested
+
+    class NoServicesBlock(XBlock):
+        """XBlock requesting no services"""
+
+    no_services_block = NoServicesBlock(None, None, None)
+    assert not NoServicesBlock._services_requested
+    assert not no_services_block._services_requested
 
     @XBlock.needs("n")
     @XBlock.wants("w")
@@ -811,6 +817,7 @@ class SubServiceUsingBlock(ServiceUsingBlock):
     assert sub_service_using_block.service_declaration("w1") == "want"
     assert sub_service_using_block.service_declaration("n2") == "need"
     assert sub_service_using_block.service_declaration("w2") == "want"
+    assert sub_service_using_block.service_declaration("field-data") == "need"
     assert sub_service_using_block.service_declaration("xx") is None
 
 

xblock/test/test_parsing.py

@@ -344,7 +344,7 @@ def test_dict_and_list_export_format(self):
     def test_unknown_field_as_attribute_raises_warning(self, parameter_name):
         with mock.patch('logging.warning') as patched_warn:
             block = self.parse_xml_to_block(f"<leaf {parameter_name}='something irrelevant'></leaf>")
-            patched_warn.assert_called_once_with("XBlock %s does not contain field %s", type(block), parameter_name)
+            patched_warn.assert_called_once_with("%s does not contain field %s", type(block), parameter_name)
 
     @XBlock.register_temp_plugin(LeafWithOption)
     @ddt.data(
@@ -361,7 +361,7 @@ def test_unknown_field_as_node_raises_warning(self, parameter_name):
         """) % (get_namespace_attrs(), parameter_name, parameter_name)
         with mock.patch('logging.warning') as patched_warn:
             block = self.parse_xml_to_block(xml)
-            patched_warn.assert_called_once_with("XBlock %s does not contain field %s", type(block), parameter_name)
+            patched_warn.assert_called_once_with("%s does not contain field %s", type(block), parameter_name)
 
 
 class TestRoundTrip(XmlTest, unittest.TestCase):