Sync pre-release CPython 3.15 branch from GitHub (2026-05-15)

Summary:
Imported python/cpython `3.15.0b1+` from upstream rev [`6136ad6`](https://www.github.com/python/cpython/commit/6136ad68010756edfc4474ad24793e62e1b9907e) (committed 2026-05-15 16:57:59+00:00).

# Commit Info

Base: (`3.15.0b1+`) - [`ed27363`](https://www.github.com/python/cpython/commit/ed27363ddf340577afd5b7b67e604489f5ee7aa3) (commit date: 2026-05-14 22:38:11+00:00)
Imported: (`3.15.0b1+`) - [`6136ad6`](https://www.github.com/python/cpython/commit/6136ad68010756edfc4474ad24793e62e1b9907e) (commit date: 2026-05-15 16:57:59+00:00)

# Noteworthy file changes

- Low-signal files (6 added) (NEWS.d, docs, .github)
- Other files (1 added)

Complete list of added/removed files: https://www.internalfb.com/intern/everpaste/?color=0&handle=GPGjXCbboa-qYZAEAO6VnR1nazkTbr0LAAAz

Differential Revision: D105416454

fbshipit-source-id: eac8a662bb6038451e448aea9eb1033348a60565

Author: generatedunixname1734921407115435

Doc/library/codecs.rst

@@ -1155,7 +1155,7 @@ particular, the following variants typically exist:
 +-----------------+--------------------------------+--------------------------------+
 | cp857           | 857, IBM857                    | Turkish                        |
 +-----------------+--------------------------------+--------------------------------+
-| cp858           | 858, IBM858                    | Western Europe                 |
+| cp858           | 858, IBM00858                  | Western Europe                 |
 +-----------------+--------------------------------+--------------------------------+
 | cp860           | 860, IBM860                    | Portuguese                     |
 +-----------------+--------------------------------+--------------------------------+
@@ -1192,7 +1192,7 @@ particular, the following variants typically exist:
 |                 |                                |                                |
 |                 |                                | .. versionadded:: 3.4          |
 +-----------------+--------------------------------+--------------------------------+
-| cp1140          | ibm1140                        | Western Europe                 |
+| cp1140          | IBM01140                       | Western Europe                 |
 +-----------------+--------------------------------+--------------------------------+
 | cp1250          | windows-1250                   | Central and Eastern Europe     |
 +-----------------+--------------------------------+--------------------------------+

Doc/library/select.rst

@@ -68,6 +68,7 @@
     "in",
     "integers",
     "lambda",
+    "lazy",
     "lists",
     "naming",
     "nonlocal",

Doc/tools/extensions/pydoc_topics.py

@@ -71,6 +71,10 @@
 
     # cp1140 codec
     '1140'               : 'cp1140',
+    'cp01140'            : 'cp1140',
+    'csibm01140'         : 'cp1140',
+    'ebcdic_us_37_euro'  : 'cp1140',
+    'ibm01140'           : 'cp1140',
     'ibm1140'            : 'cp1140',
 
     # cp1250 codec
@@ -159,8 +163,12 @@
 
     # cp858 codec
     '858'                : 'cp858',
+    'cp00858'            : 'cp858',
+    'csibm00858'         : 'cp858',
     'csibm858'           : 'cp858',
+    'ibm00858'           : 'cp858',
     'ibm858'             : 'cp858',
+    'pc_multilingual_850_euro' : 'cp858',
 
     # cp860 codec
     '860'                : 'cp860',

Lib/encodings/aliases.py

@@ -883,7 +883,16 @@ def ftpcp(source, sourcename, target, targetname = '', type = 'I'):
     type = 'TYPE ' + type
     source.voidcmd(type)
     target.voidcmd(type)
-    sourcehost, sourceport = parse227(source.sendcmd('PASV'))
+    # Don't trust the IPv4 address the source server advertises in its PASV
+    # reply: a malicious source could otherwise point the target's data
+    # connection at an arbitrary host (SSRF).  A caller that needs the old
+    # behavior can set trust_server_pasv_ipv4_address on the source FTP
+    # object.  See FTP.makepasv(), which applies the same rule.
+    untrusted_host, sourceport = parse227(source.sendcmd('PASV'))
+    if source.trust_server_pasv_ipv4_address:
+        sourcehost = untrusted_host
+    else:
+        sourcehost = source.sock.getpeername()[0]
     target.sendport(sourcehost, sourceport)
     # RFC 959: the user must "listen" [...] BEFORE sending the
     # transfer request.

Lib/ftplib.py

@@ -1845,6 +1845,7 @@ class Helper:
         'in': ('in', 'SEQUENCEMETHODS'),
         'is': 'COMPARISON',
         'lambda': ('lambda', 'FUNCTIONS'),
+        'lazy': ('lazy', 'MODULES'),
         'nonlocal': ('nonlocal', 'global NAMESPACES'),
         'not': 'BOOLEAN',
         'or': 'BOOLEAN',

Lib/pydoc.py

@@ -1,6 +1,7 @@
 import sys
 import unittest
 import test.support
+import ctypes
 from ctypes import (CDLL, PyDLL, ArgumentError,
                     Structure, Array, Union,
                     _Pointer, _SimpleCData, _CFuncPtr,
@@ -247,6 +248,13 @@ def test_parameter_repr(self):
         self.assertRegex(repr(c_char_p.from_param(b'hihi')), r"^<cparam 'z' \(0x[A-Fa-f0-9]+\)>$")
         self.assertRegex(repr(c_wchar_p.from_param('hihi')), r"^<cparam 'Z' \(0x[A-Fa-f0-9]+\)>$")
         self.assertRegex(repr(c_void_p.from_param(0x12)), r"^<cparam 'P' \(0x0*12\)>$")
+        if hasattr(ctypes, 'c_double_complex'):
+            self.assertRegex(repr(ctypes.c_double_complex.from_param(0)),
+                             r"^<cparam 'Zd' at 0x[A-Fa-f0-9]+>$")
+            self.assertRegex(repr(ctypes.c_float_complex.from_param(0)),
+                             r"^<cparam 'Zf' at 0x[A-Fa-f0-9]+>$")
+            self.assertRegex(repr(ctypes.c_longdouble_complex.from_param(0)),
+                             r"^<cparam 'Zg' at 0x[A-Fa-f0-9]+>$")
 
     @test.support.cpython_only
     def test_from_param_result_refcount(self):

Lib/test/test_ctypes/test_parameters.py

@@ -16,7 +16,7 @@
 except ImportError:
     ssl = None
 
-from unittest import TestCase, skipUnless
+from unittest import mock, TestCase, skipUnless
 from test import support
 from test.support import requires_subprocess
 from test.support import threading_helper
@@ -1145,6 +1145,40 @@ def testTimeoutDirectAccess(self):
         ftp.close()
 
 
+class TestFtpcpSecurity(TestCase):
+    """ftpcp() must not trust the host a source server advertises in PASV.
+
+    A malicious source server can otherwise redirect the target server's
+    data connection to an arbitrary host:port (SSRF), so ftpcp() uses the
+    source server's actual peer address instead, the same as FTP.makepasv().
+    """
+
+    def _make_pair(self, *, advertised_host, real_host, trust=False):
+        source = mock.Mock(spec=ftplib.FTP)
+        source.trust_server_pasv_ipv4_address = trust
+        source.sock.getpeername.return_value = (real_host, 21)
+        # PASV replies give the host as comma-separated octets, not dotted.
+        advertised = advertised_host.replace('.', ',')
+        source.sendcmd.side_effect = lambda cmd: (
+            f'227 Entering Passive Mode ({advertised},1,2).'
+            if cmd == 'PASV' else '150 ok')
+        target = mock.Mock(spec=ftplib.FTP)
+        target.sendcmd.return_value = '150 ok'
+        return source, target
+
+    def test_ftpcp_ignores_untrusted_pasv_host(self):
+        source, target = self._make_pair(advertised_host='10.0.0.5',
+                                         real_host='198.51.100.7')
+        ftplib.ftpcp(source, 'a', target, 'b')
+        target.sendport.assert_called_once_with('198.51.100.7', 258)
+
+    def test_ftpcp_trust_server_pasv_ipv4_address(self):
+        source, target = self._make_pair(advertised_host='10.0.0.5',
+                                         real_host='198.51.100.7', trust=True)
+        ftplib.ftpcp(source, 'a', target, 'b')
+        target.sendport.assert_called_once_with('10.0.0.5', 258)
+
+
 class MiscTestCase(TestCase):
     def test__all__(self):
         not_exported = {

Lib/test/test_ftplib.py

@@ -2172,7 +2172,7 @@ def mock_getline(prompt):
 
     def test_keywords(self):
         self.assertEqual(sorted(pydoc.Helper.keywords),
-                         sorted(keyword.kwlist))
+                         sorted(keyword.kwlist + ['lazy']))
 
     def test_interact_empty_line_continues(self):
         # gh-138568: test pressing Enter without input should continue in help session

Lib/test/test_pydoc/test_pydoc.py

@@ -301,9 +301,9 @@ def test_sysconfig(self):
                 self.assertEqual(out.strip(), expected, err)
         for attr, expected in (
             ('executable', self.envpy()),
-            # Usually compare to sys.executable, but if we're running in our own
-            # venv then we really need to compare to our base executable
-            ('_base_executable', sys._base_executable),
+            # Usually compare to sys.prefix, but if we're running in our own
+            # venv then we really need to compare to our base prefix
+            ('base_prefix', sys.base_prefix),
         ):
             with self.subTest(attr):
                 cmd[2] = f'import sys; print(sys.{attr})'
@@ -916,10 +916,10 @@ def test_venvwlauncher(self):
             exename = exename.replace("python", "pythonw")
         envpyw = os.path.join(self.env_dir, self.bindir, exename)
         try:
-            subprocess.check_call([envpyw, "-c", "import sys; "
-                "assert sys._base_executable.endswith('%s')" % exename])
+            subprocess.check_call([envpyw, "-c", "import fnmatch, sys; "
+                "assert fnmatch.fnmatch(sys._base_executable, '**/pythonw*.exe')"])
         except subprocess.CalledProcessError:
-            self.fail("venvwlauncher.exe did not run %s" % exename)
+            self.fail("venvwlauncher.exe did not run pythonw.exe")
 
 
 @requireVenvCreate