Add missing DECREF to PyErr_WriteUnraisable(). That function reports
exceptions that can't be raised any further, because (for instance) they
occur in __del__ methods. The coroutine tests in test_generators was
triggering this leak. Remove the leakers' testcase, and add a simpler
testcase that explicitly tests this leak to test_generators.
test_generators now no longer leaks at all, on my machine. This fix may also
solve other leaks, but my full refleakhunting run is still busy, so who
knows?
diff --git a/Lib/test/test_generators.py b/Lib/test/test_generators.py
index 67781c9..a60a768 100644
--- a/Lib/test/test_generators.py
+++ b/Lib/test/test_generators.py
@@ -1745,8 +1745,40 @@
>>> leak()
-There should be more test_generator-induced refleaks here, after they get
-fixed.
+
+This test isn't really generator related, but rather exception-in-cleanup
+related. The coroutine tests (above) just happen to cause an exception in
+the generator's __del__ (tp_del) method. We can also test for this
+explicitly, without generators. We do have to redirect stderr to avoid
+printing warnings and to doublecheck that we actually tested what we wanted
+to test.
+
+>>> import sys, StringIO
+>>> old = sys.stderr
+>>> try:
+... sys.stderr = StringIO.StringIO()
+... class Leaker:
+... def __del__(self):
+... raise RuntimeError
+...
+... l = Leaker()
+... del l
+... err = sys.stderr.getvalue().strip()
+... err.startswith(
+... "Exception exceptions.RuntimeError: RuntimeError() in <"
+... )
+... err.endswith("> ignored")
+... len(err.splitlines())
+... finally:
+... sys.stderr = old
+True
+True
+1
+
+
+
+These refleak tests should perhaps be in a testfile of their own,
+test_generators just happened to be the test that drew these out.
"""