From 0cdf9a36ec1b65a655a8af476077c7dd063d87da Mon Sep 17 00:00:00 2001
From: Georg Brandl <georg@python.org>
Date: Sat, 26 Jan 2008 14:14:20 +0000
Subject: [PATCH] #1473257: add generator.gi_code attribute that refers to the
 original code object backing the generator. Patch by Collin Winter.

---
 Include/genobject.h         |  3 +++
 Lib/test/test_generators.py | 20 +++++++++++++++++++-
 Misc/NEWS                   |  6 +++++-
 Objects/genobject.c         |  5 +++++
 4 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/Include/genobject.h b/Include/genobject.h
index 11c6823eaa2..135561b701b 100644
--- a/Include/genobject.h
+++ b/Include/genobject.h
@@ -18,6 +18,9 @@ typedef struct {
 
 	/* True if generator is being executed. */
 	int gi_running;
+    
+	/* The code object backing the generator */
+	PyObject *gi_code;
 
 	/* List of weak reference. */
 	PyObject *gi_weakreflist;
diff --git a/Lib/test/test_generators.py b/Lib/test/test_generators.py
index ce3db72e66c..ab0fca05064 100644
--- a/Lib/test/test_generators.py
+++ b/Lib/test/test_generators.py
@@ -382,7 +382,7 @@ From the Iterators list, about the types of these things.
 >>> type(i)
 <type 'generator'>
 >>> [s for s in dir(i) if not s.startswith('_')]
-['close', 'gi_frame', 'gi_running', 'next', 'send', 'throw']
+['close', 'gi_code', 'gi_frame', 'gi_running', 'next', 'send', 'throw']
 >>> print i.next.__doc__
 x.next() -> the next value, or raise StopIteration
 >>> iter(i) is i
@@ -899,6 +899,24 @@ This one caused a crash (see SF bug 567538):
 >>> print g.next()
 Traceback (most recent call last):
 StopIteration
+
+
+Test the gi_code attribute
+
+>>> def f():
+...     yield 5
+...
+>>> g = f()
+>>> g.gi_code is f.func_code
+True
+>>> g.next()
+5
+>>> g.next()
+Traceback (most recent call last):
+StopIteration
+>>> g.gi_code is f.func_code
+True
+
 """
 
 # conjoin is a simple backtracking generator, named in honor of Icon's
diff --git a/Misc/NEWS b/Misc/NEWS
index 16034183e4e..2d463571d4b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,7 +12,11 @@ What's New in Python 2.6 alpha 1?
 Core and builtins
 -----------------
 
-- Backport of PyUnicode_FromString(), _FromStringAndSize(), _Format and
+- Patch #1473257: generator objects gain a gi_code attribute. This is the
+  same object as the func_code attribute of the function that produced the
+  generator.
+
+ Backport of PyUnicode_FromString(), _FromStringAndSize(), _Format and
   _FormatV from Python 3.0. Made PyLong_AsSsize_t and PyLong_FromSsize_t
   public functions.
 
diff --git a/Objects/genobject.c b/Objects/genobject.c
index 4ef710bfcd9..38682955c3a 100644
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -11,6 +11,7 @@ static int
 gen_traverse(PyGenObject *gen, visitproc visit, void *arg)
 {
 	Py_VISIT((PyObject *)gen->gi_frame);
+	Py_VISIT(gen->gi_code);
 	return 0;
 }
 
@@ -35,6 +36,7 @@ gen_dealloc(PyGenObject *gen)
 
 	_PyObject_GC_UNTRACK(self);
 	Py_CLEAR(gen->gi_frame);
+	Py_CLEAR(gen->gi_code);
 	PyObject_GC_Del(gen);
 }
 
@@ -282,6 +284,7 @@ gen_iternext(PyGenObject *gen)
 static PyMemberDef gen_memberlist[] = {
 	{"gi_frame",	T_OBJECT, offsetof(PyGenObject, gi_frame),	RO},
 	{"gi_running",	T_INT,    offsetof(PyGenObject, gi_running),	RO},
+        {"gi_code",     T_OBJECT, offsetof(PyGenObject, gi_code),  RO},
 	{NULL}	/* Sentinel */
 };
 
@@ -352,6 +355,8 @@ PyGen_New(PyFrameObject *f)
 		return NULL;
 	}
 	gen->gi_frame = f;
+	Py_INCREF(f->f_code);
+	gen->gi_code = (PyObject *)(f->f_code);
 	gen->gi_running = 0;
 	gen->gi_weakreflist = NULL;
 	_PyObject_GC_TRACK(gen);