Add a new warning gategory, ResourceWarning, as discussed on python-dev. It is silent by default,

except when configured --with-pydebug.

Emit this warning from the GC shutdown procedure, rather than just printing to stderr.

3 files changed, 13 insertions, 3 deletions

diff --git a/Lib/test/exception_hierarchy.txt b/Lib/test/exception_hierarchy.txt
index 73ccb66..5037b33 100644
--- a/Lib/test/exception_hierarchy.txt
+++ b/Lib/test/exception_hierarchy.txt
@@ -47,3 +47,4 @@ BaseException
            +-- ImportWarning
            +-- UnicodeWarning
            +-- BytesWarning
+           +-- ResourceWarning
diff --git a/Lib/test/test_gc.py b/Lib/test/test_gc.py
index 6c8907d..9de7c29 100644
--- a/Lib/test/test_gc.py
+++ b/Lib/test/test_gc.py
@@ -485,7 +485,7 @@ class GCTests(unittest.TestCase):
             gc.set_debug(%s)
         """
         def run_command(code):
-            p = subprocess.Popen([sys.executable, "-c", code],
+            p = subprocess.Popen([sys.executable, "-Wd", "-c", code],
                 stdout=subprocess.PIPE,
                 stderr=subprocess.PIPE)
             stdout, stderr = p.communicate()
@@ -494,11 +494,13 @@ class GCTests(unittest.TestCase):
             return strip_python_stderr(stderr)
 
         stderr = run_command(code % "0")
-        self.assertIn(b"gc: 2 uncollectable objects at shutdown", stderr)
+        self.assertIn(b"ResourceWarning: gc: 2 uncollectable objects at "
+                      b"shutdown; use", stderr)
         self.assertNotIn(b"<X 'first'>", stderr)
         # With DEBUG_UNCOLLECTABLE, the garbage list gets printed
         stderr = run_command(code % "gc.DEBUG_UNCOLLECTABLE")
-        self.assertIn(b"gc: 2 uncollectable objects at shutdown", stderr)
+        self.assertIn(b"ResourceWarning: gc: 2 uncollectable objects at "
+                      b"shutdown", stderr)
         self.assertTrue(
             (b"[<X 'first'>, <X 'second'>]" in stderr) or
             (b"[<X 'second'>, <X 'first'>]" in stderr), stderr)
diff --git a/Lib/warnings.py b/Lib/warnings.py
index a81aab3..5b5821b 100644
--- a/Lib/warnings.py
+++ b/Lib/warnings.py
@@ -383,4 +383,11 @@ if not _warnings_defaults:
     else:
         bytes_action = "ignore"
     simplefilter(bytes_action, category=BytesWarning, append=1)
+    # resource usage warnings are enabled by default in pydebug mode
+    if hasattr(sys, 'gettotalrefcount'):
+        resource_action = "always"
+    else:
+        resource_action = "ignore"
+    simplefilter(resource_action, category=ResourceWarning, append=1)
+
 del _warnings_defaults