Convert "__init__ should return None" from an exception to a warning.

2 files changed, 12 insertions, 5 deletions

diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 26df0f2..4af59b0 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -3965,17 +3965,23 @@ def vicious_descriptor_nonsense():
     import gc; gc.collect()
     vereq(hasattr(c, 'attr'), False)
 
+import warnings
+
 def test_init():
     # SF 1155938
     class Foo(object):
         def __init__(self):
             return 10
+
+    oldfilters = warnings.filters
+    warnings.filterwarnings("error", category=RuntimeWarning)
     try:
         Foo()
-    except TypeError:
+    except RuntimeWarning:
         pass
     else:
         raise TestFailed, "did not test __init__() for None return"
+    warnings.filters = oldfilters
 
 
 def test_main():
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 6c31c73..26fe2a1 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -4754,10 +4754,11 @@ slot_tp_init(PyObject *self, PyObject *args, PyObject *kwds)
 	if (res == NULL)
 		return -1;
 	if (res != Py_None) {
-		PyErr_SetString(PyExc_TypeError,
-			   "__init__() should return None");
-		Py_DECREF(res);
-		return -1;
+		if (PyErr_Warn(PyExc_RuntimeWarning, 
+			"__init__() should return None") == -1) {
+			Py_DECREF(res);
+			return -1;
+		}
 	}
 	Py_DECREF(res);
 	return 0;