Merge branch 'main' into setobject-note

Author: iritkatriel

Lib/asyncio/tasks.py

@@ -25,7 +25,6 @@
 from . import exceptions
 from . import futures
 from . import timeouts
-from .coroutines import _is_coroutine
 
 # Helper to generate new task names
 # This uses itertools.count() instead of a "+= 1" operation because the latter
@@ -635,11 +634,14 @@ def ensure_future(coro_or_future, *, loop=None):
             raise ValueError('The future belongs to a different loop than '
                             'the one specified as the loop argument')
         return coro_or_future
-    called_wrap_awaitable = False
+    should_close = True
     if not coroutines.iscoroutine(coro_or_future):
         if inspect.isawaitable(coro_or_future):
+            async def _wrap_awaitable(awaitable):
+                return await awaitable
+
             coro_or_future = _wrap_awaitable(coro_or_future)
-            called_wrap_awaitable = True
+            should_close = False
         else:
             raise TypeError('An asyncio.Future, a coroutine or an awaitable '
                             'is required')
@@ -649,23 +651,11 @@ def ensure_future(coro_or_future, *, loop=None):
     try:
         return loop.create_task(coro_or_future)
     except RuntimeError:
-        if not called_wrap_awaitable:
+        if should_close:
             coro_or_future.close()
         raise
 
 
-@types.coroutine
-def _wrap_awaitable(awaitable):
-    """Helper for asyncio.ensure_future().
-
-    Wraps awaitable (an object with __await__) into a coroutine
-    that will later be wrapped in a Task by ensure_future().
-    """
-    return (yield from awaitable.__await__())
-
-_wrap_awaitable._is_coroutine = _is_coroutine
-
-
 class _GatheringFuture(futures.Future):
     """Helper for gather().
 

Lib/concurrent/futures/process.py

@@ -366,6 +366,11 @@ def run(self):
             if self.is_shutting_down():
                 self.flag_executor_shutting_down()
 
+                # When only canceled futures remain in pending_work_items, our
+                # next call to wait_result_broken_or_wakeup would hang forever.
+                # This makes sure we have some running futures or none at all.
+                self.add_call_item_to_queue()
+
                 # Since no new work items can be added, it is safe to shutdown
                 # this thread if there are no pending work items.
                 if not self.pending_work_items:

Lib/test/test_asyncio/test_tasks.py

@@ -8,6 +8,7 @@
 import re
 import sys
 import traceback
+import types
 import unittest
 from unittest import mock
 from types import GenericAlias
@@ -274,6 +275,20 @@ async def coro():
         loop.run_until_complete(fut)
         self.assertEqual(fut.result(), 'ok')
 
+    def test_ensure_future_task_awaitable(self):
+        class Aw:
+            def __await__(self):
+                return asyncio.sleep(0, result='ok').__await__()
+
+        loop = asyncio.new_event_loop()
+        self.set_event_loop(loop)
+        task = asyncio.ensure_future(Aw(), loop=loop)
+        loop.run_until_complete(task)
+        self.assertTrue(task.done())
+        self.assertEqual(task.result(), 'ok')
+        self.assertIsInstance(task.get_coro(), types.CoroutineType)
+        loop.close()
+
     def test_ensure_future_neither(self):
         with self.assertRaises(TypeError):
             asyncio.ensure_future('ok')

Lib/test/test_concurrent_futures.py

@@ -14,6 +14,7 @@
 from logging.handlers import QueueHandler
 import os
 import queue
+import signal
 import sys
 import threading
 import time
@@ -397,6 +398,33 @@ def test_hang_gh83386(self):
         self.assertFalse(err)
         self.assertEqual(out.strip(), b"apple")
 
+    def test_hang_gh94440(self):
+        """shutdown(wait=True) doesn't hang when a future was submitted and
+        quickly canceled right before shutdown.
+
+        See https://github.com/python/cpython/issues/94440.
+        """
+        if not hasattr(signal, 'alarm'):
+            raise unittest.SkipTest(
+                "Tested platform does not support the alarm signal")
+
+        def timeout(_signum, _frame):
+            raise RuntimeError("timed out waiting for shutdown")
+
+        kwargs = {}
+        if getattr(self, 'ctx', None):
+            kwargs['mp_context'] = self.get_context()
+        executor = self.executor_type(max_workers=1, **kwargs)
+        executor.submit(int).result()
+        old_handler = signal.signal(signal.SIGALRM, timeout)
+        try:
+            signal.alarm(5)
+            executor.submit(int).cancel()
+            executor.shutdown(wait=True)
+        finally:
+            signal.alarm(0)
+            signal.signal(signal.SIGALRM, old_handler)
+
 
 class ThreadPoolShutdownTest(ThreadPoolMixin, ExecutorShutdownTest, BaseTestCase):
     def test_threads_terminate(self):

Lib/webbrowser.py

@@ -542,11 +542,15 @@ def register_standard_browsers():
         # First try to use the default Windows browser
         register("windows-default", WindowsDefault)
 
-        # Detect some common Windows browsers, fallback to IE
-        iexplore = os.path.join(os.environ.get("PROGRAMFILES", "C:\\Program Files"),
-                                "Internet Explorer\\IEXPLORE.EXE")
+        # Detect some common Windows browsers, fallback to Microsoft Edge
+        # location in 64-bit Windows
+        edge64 = os.path.join(os.environ.get("PROGRAMFILES(x86)", "C:\\Program Files (x86)"),
+                              "Microsoft\\Edge\\Application\\msedge.exe")
+        # location in 32-bit Windows
+        edge32 = os.path.join(os.environ.get("PROGRAMFILES", "C:\\Program Files"),
+                              "Microsoft\\Edge\\Application\\msedge.exe")
         for browser in ("firefox", "firebird", "seamonkey", "mozilla",
-                        "netscape", "opera", iexplore):
+                        "opera", edge64, edge32):
             if shutil.which(browser):
                 register(browser, None, BackgroundBrowser(browser))
     else:

Misc/ACKS

@@ -1385,6 +1385,7 @@ Thomas Perl
 Mathieu Perreault
 Mark Perrego
 Trevor Perrin
+Yonatan Perry
 Gabriel de Perthuis
 Tim Peters
 Benjamin Peterson

Misc/NEWS.d/next/Library/2022-06-30-21-28-41.gh-issue-94440.LtgX0d.rst

@@ -0,0 +1,2 @@
+Fix a :mod:`concurrent.futures.process` bug where ``ProcessPoolExecutor`` shutdown
+could hang after a future has been quickly submitted and canceled.

Misc/NEWS.d/next/Library/2023-03-10-13-51-21.gh-issue-100112.VHh4mw.rst

@@ -0,0 +1 @@
+:meth:`asyncio.Task.get_coro` now always returns a coroutine when wrapping an awaitable object. Patch by Kumar Aditya.

Misc/NEWS.d/next/Windows/2023-03-14-10-52-43.gh-issue-102690.sbXtqk.rst

@@ -0,0 +1 @@
+Update :mod:`webbrowser` to fall back to Microsoft Edge instead of Internet Explorer.

Python/bltinmodule.c

@@ -3098,9 +3098,6 @@ _PyBuiltin_Init(PyInterpreterState *interp)
     }
     Py_DECREF(debug);
 
-    /* m_copy of Py_None means it is copied some other way. */
-    builtinsmodule.m_base.m_copy = Py_NewRef(Py_None);
-
     return mod;
 #undef ADD_TO_ALL
 #undef SETBUILTIN

Python/import.c

@@ -978,14 +978,29 @@ _PyImport_CheckSubinterpIncompatibleExtensionAllowed(const char *name)
     return 0;
 }
 
-static inline int
-match_mod_name(PyObject *actual, const char *expected)
+static PyObject *
+get_core_module_dict(PyInterpreterState *interp,
+                     PyObject *name, PyObject *filename)
 {
-    if (PyUnicode_CompareWithASCIIString(actual, expected) == 0) {
-        return 1;
+    /* Only builtin modules are core. */
+    if (filename == name) {
+        assert(!PyErr_Occurred());
+        if (PyUnicode_CompareWithASCIIString(name, "sys") == 0) {
+            return interp->sysdict_copy;
+        }
+        assert(!PyErr_Occurred());
+        if (PyUnicode_CompareWithASCIIString(name, "builtins") == 0) {
+            return interp->builtins_copy;
+        }
+        assert(!PyErr_Occurred());
     }
-    assert(!PyErr_Occurred());
-    return 0;
+    return NULL;
+}
+
+static inline int
+is_core_module(PyInterpreterState *interp, PyObject *name, PyObject *filename)
+{
+    return get_core_module_dict(interp, name, filename) != NULL;
 }
 
 static int
@@ -1009,10 +1024,8 @@ fix_up_extension(PyObject *mod, PyObject *name, PyObject *filename)
 
     // bpo-44050: Extensions and def->m_base.m_copy can be updated
     // when the extension module doesn't support sub-interpreters.
-    // XXX Why special-case the main interpreter?
-    if (_Py_IsMainInterpreter(tstate->interp) || def->m_size == -1) {
-        /* m_copy of Py_None means it is copied some other way. */
-        if (def->m_size == -1 && def->m_base.m_copy != Py_None) {
+    if (def->m_size == -1) {
+        if (!is_core_module(tstate->interp, name, filename)) {
             if (def->m_base.m_copy) {
                 /* Somebody already imported the module,
                    likely under a different name.
@@ -1028,7 +1041,10 @@ fix_up_extension(PyObject *mod, PyObject *name, PyObject *filename)
                 return -1;
             }
         }
+    }
 
+    // XXX Why special-case the main interpreter?
+    if (_Py_IsMainInterpreter(tstate->interp) || def->m_size == -1) {
         if (_extensions_cache_set(filename, name, def) < 0) {
             return -1;
         }
@@ -1069,21 +1085,11 @@ import_find_extension(PyThreadState *tstate, PyObject *name,
         PyObject *m_copy = def->m_base.m_copy;
         /* Module does not support repeated initialization */
         if (m_copy == NULL) {
-            return NULL;
-        }
-        else if (m_copy == Py_None) {
-            if (match_mod_name(name, "sys")) {
-                m_copy = tstate->interp->sysdict_copy;
-            }
-            else if (match_mod_name(name, "builtins")) {
-                m_copy = tstate->interp->builtins_copy;
-            }
-            else {
-                _PyErr_SetString(tstate, PyExc_ImportError, "missing m_copy");
+            m_copy = get_core_module_dict(tstate->interp, name, filename);
+            if (m_copy == NULL) {
                 return NULL;
             }
         }
-        /* m_copy of Py_None means it is copied some other way. */
         mod = import_add_module(tstate, name);
         if (mod == NULL) {
             return NULL;

Python/sysmodule.c

@@ -3425,9 +3425,6 @@ _PySys_Create(PyThreadState *tstate, PyObject **sysmod_p)
         return _PyStatus_ERR("failed to create a module object");
     }
 
-    /* m_copy of Py_None means it is copied some other way. */
-    sysmodule.m_base.m_copy = Py_NewRef(Py_None);
-
     PyObject *sysdict = PyModule_GetDict(sysmod);
     if (sysdict == NULL) {
         goto error;