https://github.com/python/cpython/commit/847d1c2cb4014f122df64e0db0b3b554c01779c6 commit: 847d1c2cb4014f122df64e0db0b3b554c01779c6 branch: main author: Pieter Eendebak <[email protected]> committer: kumaraditya303 <[email protected]> date: 2025-06-30T11:31:59Z summary:
gh-123471: Make itertools.product and itertools.combinations thread-safe (#132814) Co-authored-by: Kumar Aditya <[email protected]> files: A Lib/test/test_free_threading/test_itertools_combinatoric.py A Misc/NEWS.d/next/Library/2025-04-22-21-00-23.gh-issue-123471.asOLA2.rst M Modules/itertoolsmodule.c diff --git a/Lib/test/test_free_threading/test_itertools_combinatoric.py b/Lib/test/test_free_threading/test_itertools_combinatoric.py new file mode 100644 index 00000000000000..5b3b88deedd121 --- /dev/null +++ b/Lib/test/test_free_threading/test_itertools_combinatoric.py @@ -0,0 +1,51 @@ +import unittest +from threading import Thread, Barrier +from itertools import combinations, product +from test.support import threading_helper + + +threading_helper.requires_working_threading(module=True) + +def test_concurrent_iteration(iterator, number_of_threads): + barrier = Barrier(number_of_threads) + def iterator_worker(it): + barrier.wait() + while True: + try: + _ = next(it) + except StopIteration: + return + + worker_threads = [] + for ii in range(number_of_threads): + worker_threads.append( + Thread(target=iterator_worker, args=[iterator])) + + with threading_helper.start_threads(worker_threads): + pass + + barrier.reset() + +class ItertoolsThreading(unittest.TestCase): + + @threading_helper.reap_threads + def test_combinations(self): + number_of_threads = 10 + number_of_iterations = 24 + + for it in range(number_of_iterations): + iterator = combinations((1, 2, 3, 4, 5), 2) + test_concurrent_iteration(iterator, number_of_threads) + + @threading_helper.reap_threads + def test_product(self): + number_of_threads = 10 + number_of_iterations = 24 + + for it in range(number_of_iterations): + iterator = product((1, 2, 3, 4, 5), (10, 20, 30)) + test_concurrent_iteration(iterator, number_of_threads) + + +if __name__ == "__main__": + unittest.main() diff --git a/Misc/NEWS.d/next/Library/2025-04-22-21-00-23.gh-issue-123471.asOLA2.rst b/Misc/NEWS.d/next/Library/2025-04-22-21-00-23.gh-issue-123471.asOLA2.rst new file mode 100644 index 00000000000000..a4b4b6d2c23d49 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2025-04-22-21-00-23.gh-issue-123471.asOLA2.rst @@ -0,0 +1 @@ +Make concurrent iterations over :class:`itertools.combinations` and :class:`itertools.product` safe under free-threading. diff --git a/Modules/itertoolsmodule.c b/Modules/itertoolsmodule.c index e6536c250109b1..cc1a558001563c 100644 --- a/Modules/itertoolsmodule.c +++ b/Modules/itertoolsmodule.c @@ -2096,7 +2096,7 @@ product_traverse(PyObject *op, visitproc visit, void *arg) } static PyObject * -product_next(PyObject *op) +product_next_lock_held(PyObject *op) { productobject *lz = productobject_CAST(op); PyObject *pool; @@ -2182,6 +2182,16 @@ product_next(PyObject *op) return NULL; } +static PyObject * +product_next(PyObject *op) +{ + PyObject *result; + Py_BEGIN_CRITICAL_SECTION(op); + result = product_next_lock_held(op); + Py_END_CRITICAL_SECTION() + return result; +} + static PyMethodDef product_methods[] = { {"__sizeof__", product_sizeof, METH_NOARGS, sizeof_doc}, {NULL, NULL} /* sentinel */ @@ -2329,7 +2339,7 @@ combinations_traverse(PyObject *op, visitproc visit, void *arg) } static PyObject * -combinations_next(PyObject *op) +combinations_next_lock_held(PyObject *op) { combinationsobject *co = combinationsobject_CAST(op); PyObject *elem; @@ -2414,6 +2424,16 @@ combinations_next(PyObject *op) return NULL; } +static PyObject * +combinations_next(PyObject *op) +{ + PyObject *result; + Py_BEGIN_CRITICAL_SECTION(op); + result = combinations_next_lock_held(op); + Py_END_CRITICAL_SECTION() + return result; +} + static PyMethodDef combinations_methods[] = { {"__sizeof__", combinations_sizeof, METH_NOARGS, sizeof_doc}, {NULL, NULL} /* sentinel */ _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
