Propagate __name__ and __qualname__ updates as well as saving them against the wrapper.

src/_wrappers.c

@@ -327,6 +327,8 @@ static int WraptWrapperBase_setattro(
         WraptWrapperBaseObject *self, PyObject *name, PyObject *value)
 {
     PyObject *self_prefix = NULL;
+    PyObject *attr_name = NULL;
+    PyObject *attr_qualname = NULL;
 
     PyObject *match = NULL;
 
@@ -337,8 +339,12 @@ static int WraptWrapperBase_setattro(
 
 #if PY_MAJOR_VERSION >= 3
     self_prefix = PyUnicode_FromString("_self_");
+    attr_name = PyUnicode_FromString("__name__");
+    attr_qualname = PyUnicode_FromString("__qualname__");
 #else
     self_prefix = PyString_FromString("_self_");
+    attr_name = PyString_FromString("__name__");
+    attr_qualname = PyString_FromString("__qualname__");
 #endif
 
     match = PyEval_CallMethod(name, "startswith", "(O)", self_prefix);
@@ -353,6 +359,15 @@ static int WraptWrapperBase_setattro(
 
     Py_XDECREF(match);
 
+    if (PyObject_RichCompareBool(name, attr_name, Py_EQ) == 1 ||
+            PyObject_RichCompareBool(name, attr_qualname, Py_EQ) == 1) {
+
+        if (PyObject_GenericSetAttr((PyObject *)self, name, value) == -1)
+            return -1;
+
+        return PyObject_SetAttr(self->wrapped, name, value);
+    }
+
     return PyObject_SetAttr(self->wrapped, name, value);
 }
 

src/wrappers.py

@@ -61,9 +61,9 @@ class _WrapperBase(six.with_metaclass(_WrapperBaseMetaType)):
 
         try:
             if target is None:
-                object.__setattr__(self, '__qualname__', wrapped.__qualname__)
+                self.__qualname__ =  wrapped.__qualname__
             else:
-                object.__setattr__(self, '__qualname__', target.__qualname__)
+                self.__qualname__ = target.__qualname__
         except AttributeError:
             pass
 
@@ -74,15 +74,18 @@ class _WrapperBase(six.with_metaclass(_WrapperBaseMetaType)):
 
         try:
             if target is None:
-                object.__setattr__(self, '__name__', wrapped.__name__)
+                self. __name__ = wrapped.__name__
             else:
-                object.__setattr__(self, '__name__', target.__name__)
+                self.__name__ = target.__name__
         except AttributeError:
             pass
 
     def __setattr__(self, name, value):
         if name.startswith('_self_'):
             object.__setattr__(self, name, value)
+        elif name in ('__name__', '__qualname__'):
+            object.__setattr__(self, name, value)
+            setattr(self._self_wrapped, name, value)
         else:
             setattr(self._self_wrapped, name, value)
 

tests/test_update_attributes.py

@@ -0,0 +1,133 @@
+from __future__ import print_function
+
+import unittest
+
+import wrapt
+
+from wrapt import six
+
+@wrapt.decorator
+def passthru_decorator(wrapped, instance, args, kwargs):
+    return wrapped(*args, **kwargs)
+
+class TestUpdateAttributes(unittest.TestCase):
+
+    def test_update_name(self):
+        @passthru_decorator
+        def function():
+            pass
+
+        self.assertEqual(function.__name__, 'function')
+
+        function.__name__ = 'override_name'
+
+        self.assertEqual(function.__name__, 'override_name')
+
+    def test_update_name_modified_on_original(self):
+        def function():
+            pass
+
+        def wrapper(wrapped, instance, args, kwargs):
+            return wrapped(*args, **kwargs)
+
+        instance = wrapt.FunctionWrapper(function, wrapper)
+
+        self.assertEqual(instance.__name__, 'function')
+
+        instance.__name__ = 'override_name'
+
+        self.assertEqual(function.__name__, 'override_name')
+        self.assertEqual(instance.__name__, 'override_name')
+
+    def test_update_qualname(self):
+
+        @passthru_decorator
+        def function():
+            pass
+
+        if six.PY3:
+            method = self.test_update_qualname
+            self.assertEqual(function.__qualname__,
+                    (method.__qualname__ + '.<locals>.function'))
+
+        function.__qualname__ = 'override_qualname'
+
+        self.assertEqual(function.__qualname__, 'override_qualname')
+
+    def test_update_qualname_modified_on_original(self):
+        def function():
+            pass
+
+        def wrapper(wrapped, instance, args, kwargs):
+            return wrapped(*args, **kwargs)
+
+        instance = wrapt.FunctionWrapper(function, wrapper)
+
+        if six.PY3:
+            method = self.test_update_qualname_modified_on_original
+            self.assertEqual(instance.__qualname__,
+                    (method.__qualname__ + '.<locals>.function'))
+
+        instance.__qualname__ = 'override_qualname'
+
+        self.assertEqual(function.__qualname__, 'override_qualname')
+        self.assertEqual(instance.__qualname__, 'override_qualname')
+
+    def test_update_module(self):
+        @passthru_decorator
+        def function():
+            pass
+
+        self.assertEqual(function.__module__, __name__)
+
+        function.__module__ = 'override_module'
+
+        self.assertEqual(function.__module__, 'override_module')
+
+    def test_update_module_modified_on_original(self):
+        def function():
+            pass
+
+        def wrapper(wrapped, instance, args, kwargs):
+            return wrapped(*args, **kwargs)
+
+        instance = wrapt.FunctionWrapper(function, wrapper)
+
+        self.assertEqual(instance.__module__, __name__)
+
+        instance.__module__ = 'override_module'
+
+        self.assertEqual(function.__module__, 'override_module')
+        self.assertEqual(instance.__module__, 'override_module')
+
+    def test_update_doc(self):
+        @passthru_decorator
+        def function():
+            """documentation"""
+            pass
+
+        self.assertEqual(function.__doc__, "documentation")
+
+        function.__doc__ = 'override_doc'
+
+        self.assertEqual(function.__doc__, 'override_doc')
+
+    def test_update_doc_modified_on_original(self):
+        def function():
+            """documentation"""
+            pass
+
+        def wrapper(wrapped, instance, args, kwargs):
+            return wrapped(*args, **kwargs)
+
+        instance = wrapt.FunctionWrapper(function, wrapper)
+
+        self.assertEqual(instance.__doc__, "documentation")
+
+        instance.__doc__ = 'override_doc'
+
+        self.assertEqual(function.__doc__, 'override_doc')
+        self.assertEqual(instance.__doc__, 'override_doc')
+
+if __name__ == '__main__':
+    unittest.main()