Do not inherit redundant docstrings

Closes #240

CHANGELOG.rst

@@ -12,6 +12,9 @@ Features
 * The fully qualified path of objects are included type annotations
   so that Sphinx can link to them.
 * Added support for Sphinx 3.3. and 3.4.
+* `#240 <https://github.com/readthedocs/sphinx-autoapi/issues/240>`:
+  The docstrings of ``object.__init__``, ``object.__new__``,
+  ``type.__init__``, and ``type.__new__`` are not inherited.
 
 Bug Fixes
 ^^^^^^^^^

autoapi/mappers/python/astroid_utils.py

@@ -599,6 +599,12 @@ def get_func_docstring(node):
 
     if doc is None and isinstance(node.parent, astroid.nodes.ClassDef):
         for base in node.parent.ancestors():
+            if node.name in ("__init__", "__new__") and base.qname() in (
+                "__builtins__.object",
+                "builtins.object",
+                "builtins.type",
+            ):
+                continue
             for child in base.get_children():
                 if (
                     isinstance(child, node.__class__)
@@ -620,7 +626,11 @@ def get_class_docstring(node):
 
     if doc is None:
         for base in node.ancestors():
-            if base.qname() in ("__builtins__.object", "builtins.object"):
+            if base.qname() in (
+                "__builtins__.object",
+                "builtins.object",
+                "builtins.type",
+            ):
                 continue
             if base.doc is not None:
                 return base.doc

docs/maintenance/design.rst

@@ -5,7 +5,7 @@ Python
 ------
 
 When choosing what to document,
-AutoAPI aims to document anything that is accessible through the actual package
+AutoAPI aims to document anything that is publicly accessible through the actual package
 when loaded in Python.
 For example if a function is imported from a submodule into a package,
 that function is documented in both the submodule and the package.
@@ -15,6 +15,20 @@ There are some exceptions to this rule:
   Usually a module is where implementations exist.
   Therefore an import of something is usually for the usage of the implementation,
   and not as something to be accessed publicly.
+* When the module or package defines an ``__all__``,
+  only the members named in ``__all__`` are documented.
+* When a configuration option indicates that private
+  or special members should also be documented.
+
+Furthermore, AutoAPI follows the same docstring inheritance rules as :func:`inspect.getdoc`,
+with some exceptions:
+
+* The docstrings of the following methods are not inherited because they are usually redundant:
+
+  * :meth:`object.__init__`
+  * :meth:`object.__new__`
+  * :meth:`type.__init__`
+  * :meth:`type.__new__`
 
 
 .NET

tests/python/test_pyintegration.py

@@ -163,6 +163,14 @@ class TestPy3Module(object):
     def built(self, builder):
         builder("py3example")
 
+    def test_integration(self):
+        example_path = "_build/text/autoapi/example/index.txt"
+        with io.open(example_path, encoding="utf8") as example_handle:
+            example_file = example_handle.read()
+
+        assert "Initialize self" not in example_file
+        assert "a new type" not in example_file
+
     def test_annotations(self):
         example_path = "_build/text/autoapi/example/index.txt"
         with io.open(example_path, encoding="utf8") as example_handle: