Update docs about catalogs inheritance

docs/catalogs/index.rst

@@ -45,16 +45,23 @@ Example:
 Operating with catalog providers
 --------------------------------
 
-There are several things that could be useful for operating with catalog
+``di.AbstractCatalog`` has several features that could be useful for some kind 
-providers:
+of operations on catalog's providers:
 
-- First of all, ``di.AbstractCatalog.providers`` attribute contains ``dict`` 
+- ``di.AbstractCatalog.providers`` is read-only attribute that contains 
-  with all catalog providers. This dictionary could be used for any kind of 
+  ``dict`` of all catalog providers, including providers that are inherited 
-  operations that could be done with providers. The only note, is that 
+  from parent catalogs, where key is the name of provider and value is 
-  ``di.AbstractCatalog.providers`` attribute is read-only.
+  provider itself.
-- Second one, ``di.AbstractCatalog.filter(provider_type=di.Provider)`` method 
+- ``di.AbstractCatalog.cls_providers`` is read-only attribute contains ``dict``
-  could be used for filtering catalog providers by provider types (for example,
+  of current catalog providers, where key is the name of provider and value is 
-  for getting all ``di.Factory`` providers).
+  provider itself.
+- ``di.AbstractCatalog.inherited_providers`` is read-only attribute contains 
+  ``dict`` of all providers that are inherited from parent catalogs, where key 
+  is the name of provider and value is provider itself. 
+- ``di.AbstractCatalog.filter(provider_type=di.Provider)`` is a class method 
+  that could be used for filtering catalog providers by provider types 
+  (for example, for getting all ``di.Factory`` providers). 
+  ``di.AbstractCatalog.filter()`` method use ``di.AbstractCatalog.providers``.
 
 Example:
 

docs/main/changelog.rst

@@ -12,6 +12,7 @@ Development version
 -------------------
 
 - Add functionality for decorating classes with ``@di.inject``.
+- Add enhancement for ``di.AbstractCatalog`` inheritance.
 
 0.9.5
 -----

examples/catalogs/operating_with_providers.py

@@ -3,29 +3,35 @@
 import dependency_injector as di
 
 
-class Catalog(di.AbstractCatalog):
+class CatalogA(di.AbstractCatalog):
 
-    """Providers catalog."""
+    """Example catalog A."""
 
     provider1 = di.Factory(object)
     """:type: (di.Provider) -> object"""
 
-    provider2 = di.Factory(object)
-    """:type: (di.Provider) -> object"""
 
-    provider3 = di.Singleton(object)
+class CatalogB(CatalogA):
-    """:type: (di.Provider) -> object"""
 
-    provider4 = di.Singleton(object)
+    """Example catalog B."""
+
+    provider2 = di.Singleton(object)
     """:type: (di.Provider) -> object"""
 
 
-# Making some asserts:
+# Making some asserts for `providers` attribute:
-assert Catalog.providers == dict(provider1=Catalog.provider1,
+assert CatalogA.providers == dict(provider1=CatalogA.provider1)
-                                 provider2=Catalog.provider2,
+assert CatalogB.providers == dict(provider1=CatalogA.provider1,
-                                 provider3=Catalog.provider3,
+                                  provider2=CatalogB.provider2)
-                                 provider4=Catalog.provider4)
+
-assert Catalog.filter(di.Factory) == dict(provider1=Catalog.provider1,
+# Making some asserts for `cls_providers` attribute:
-                                          provider2=Catalog.provider2)
+assert CatalogA.cls_providers == dict(provider1=CatalogA.provider1)
-assert Catalog.filter(di.Singleton) == dict(provider3=Catalog.provider3,
+assert CatalogB.cls_providers == dict(provider2=CatalogB.provider2)
-                                            provider4=Catalog.provider4)
+
+# Making some asserts for `inherited_providers` attribute:
+assert CatalogA.inherited_providers == dict()
+assert CatalogB.inherited_providers == dict(provider1=CatalogA.provider1)
+
+# Making some asserts for `filter()` method:
+assert CatalogB.filter(di.Factory) == dict(provider1=CatalogA.provider1)
+assert CatalogB.filter(di.Singleton) == dict(provider2=CatalogB.provider2)