diff options
Diffstat (limited to 'Lib/test/test_gc.py')
| -rw-r--r-- | Lib/test/test_gc.py | 89 |
1 files changed, 25 insertions, 64 deletions
diff --git a/Lib/test/test_gc.py b/Lib/test/test_gc.py index b5140057a69..96ebb23f73d 100644 --- a/Lib/test/test_gc.py +++ b/Lib/test/test_gc.py @@ -7,7 +7,7 @@ from test.support import (verbose, refcount_test, Py_GIL_DISABLED) from test.support.import_helper import import_module from test.support.os_helper import temp_dir, TESTFN, unlink -from test.support.script_helper import assert_python_ok, make_script +from test.support.script_helper import assert_python_ok, make_script, run_test_script from test.support import threading_helper, gc_threshold import gc @@ -262,9 +262,11 @@ class GCTests(unittest.TestCase): # finalizer. def __del__(self): - # 5. Create a weakref to `func` now. If we had created - # it earlier, it would have been cleared by the - # garbage collector before calling the finalizers. + # 5. Create a weakref to `func` now. In previous + # versions of Python, this would avoid having it + # cleared by the garbage collector before calling + # the finalizers. Now, weakrefs get cleared after + # calling finalizers. self[1].ref = weakref.ref(self[0]) # 6. Drop the global reference to `latefin`. The only @@ -293,14 +295,18 @@ class GCTests(unittest.TestCase): # which will find `cyc` and `func` as garbage. gc.collect() - # 9. Previously, this would crash because `func_qualname` - # had been NULL-ed out by func_clear(). + # 9. Previously, this would crash because the weakref + # created in the finalizer revealed the function after + # `tp_clear` was called and `func_qualname` + # had been NULL-ed out by func_clear(). Now, we clear + # weakrefs to unreachable objects before calling `tp_clear` + # but after calling finalizers. print(f"{func=}") """ - # We're mostly just checking that this doesn't crash. rc, stdout, stderr = assert_python_ok("-c", code) self.assertEqual(rc, 0) - self.assertRegex(stdout, rb"""\A\s*func=<function at \S+>\s*\Z""") + # The `func` global is None because the weakref was cleared. + self.assertRegex(stdout, rb"""\A\s*func=None""") self.assertFalse(stderr) @refcount_test @@ -726,6 +732,9 @@ class GCTests(unittest.TestCase): self.assertIn(b"ResourceWarning: gc: 2 uncollectable objects at " b"shutdown; use", stderr) self.assertNotIn(b"<X 'first'>", stderr) + one_line_re = b"gc: uncollectable <X 0x[0-9A-Fa-f]+>" + expected_re = one_line_re + b"\r?\n" + one_line_re + self.assertNotRegex(stderr, expected_re) # With DEBUG_UNCOLLECTABLE, the garbage list gets printed stderr = run_command(code % "gc.DEBUG_UNCOLLECTABLE") self.assertIn(b"ResourceWarning: gc: 2 uncollectable objects at " @@ -733,6 +742,8 @@ class GCTests(unittest.TestCase): self.assertTrue( (b"[<X 'first'>, <X 'second'>]" in stderr) or (b"[<X 'second'>, <X 'first'>]" in stderr), stderr) + # we expect two lines with uncollectable objects + self.assertRegex(stderr, expected_re) # With DEBUG_SAVEALL, no additional message should get printed # (because gc.garbage also contains normally reclaimable cyclic # references, and its elements get printed at runtime anyway). @@ -914,7 +925,7 @@ class GCTests(unittest.TestCase): gc.collect() self.assertEqual(len(Lazarus.resurrected_instances), 1) instance = Lazarus.resurrected_instances.pop() - self.assertTrue(hasattr(instance, "cargo")) + self.assertHasAttr(instance, "cargo") self.assertEqual(id(instance.cargo), cargo_id) gc.collect() @@ -1127,64 +1138,14 @@ class GCTests(unittest.TestCase): class IncrementalGCTests(unittest.TestCase): - - def setUp(self): - # Reenable GC as it is disabled module-wide - gc.enable() - - def tearDown(self): - gc.disable() - @unittest.skipIf(_testinternalcapi is None, "requires _testinternalcapi") @requires_gil_enabled("Free threading does not support incremental GC") - # Use small increments to emulate longer running process in a shorter time - @gc_threshold(200, 10) def test_incremental_gc_handles_fast_cycle_creation(self): - - class LinkedList: - - #Use slots to reduce number of implicit objects - __slots__ = "next", "prev", "surprise" - - def __init__(self, next=None, prev=None): - self.next = next - if next is not None: - next.prev = self - self.prev = prev - if prev is not None: - prev.next = self - - def make_ll(depth): - head = LinkedList() - for i in range(depth): - head = LinkedList(head, head.prev) - return head - - head = make_ll(1000) - count = 1000 - - # There will be some objects we aren't counting, - # e.g. the gc stats dicts. This test checks - # that the counts don't grow, so we try to - # correct for the uncounted objects - # This is just an estimate. - CORRECTION = 20 - - enabled = gc.isenabled() - gc.enable() - olds = [] - initial_heap_size = _testinternalcapi.get_tracked_heap_size() - for i in range(20_000): - newhead = make_ll(20) - count += 20 - newhead.surprise = head - olds.append(newhead) - if len(olds) == 20: - new_objects = _testinternalcapi.get_tracked_heap_size() - initial_heap_size - self.assertLess(new_objects, 27_000, f"Heap growing. Reached limit after {i} iterations") - del olds[:] - if not enabled: - gc.disable() + # Run this test in a fresh process. The number of alive objects (which can + # be from unit tests run before this one) can influence how quickly cyclic + # garbage is found. + script = support.findfile("_test_gc_fast_cycles.py") + run_test_script(script) class GCCallbackTests(unittest.TestCase): |