Import CPython 3.14.6+ stable branch (2026-08-03)

Summary:
Imported python/cpython `3.14.6+` from upstream rev [`1f574b1`](https://www.github.com/python/cpython/commit/1f574b1ce58067f9fdaad0b5ff9a3bfb87151e4c) (committed 2026-08-03 21:14:27+00:00).

# Commit Info

- Base: (`3.14.6+`) - [`b0ef8b4`](https://www.github.com/python/cpython/commit/b0ef8b4f3ee5dd52748bfa991cfc765edd26e8f9) (commit date: 2026-08-02 18:18:09+00:00)
- Imported: (`3.14.6+`) - [`1f574b1`](https://www.github.com/python/cpython/commit/1f574b1ce58067f9fdaad0b5ff9a3bfb87151e4c) (commit date: 2026-08-03 21:14:27+00:00)

# Noteworthy file changes

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

Complete list of added/removed files: https://www.internalfb.com/intern/everpaste/?color=0&handle=GEhVgRY5LDPBVV0DAGr-MV3qj7BVbr0LAAAz

Reviewed By: itamaro

Differential Revision: D114726860

fbshipit-source-id: 0322f8940c8ebe5e1aa6df48589371fa07c256f4

Author: generatedunixname1734921407115435

Lib/csv.py

@@ -249,6 +249,8 @@ def sniff(self, sample, delimiters=None):
         that order, no matter how many times each of them occurs.
         """
 
+        sample = sample.replace('\r\n', '\n').replace('\r', '\n')
+
         quotechar, doublequote, delimiter, skipinitialspace = \
                    self._guess_quote_and_delimiter(sample, delimiters)
         if not delimiter:
@@ -334,18 +336,22 @@ def _guess_quote_and_delimiter(self, data, delimiters):
             delim = ''
             skipinitialspace = 0
 
-        # if we see an extra quote between delimiters, we've got a
-        # double quoted format
-        dq_regexp = re.compile(
-                               r"((%(delim)s)|^)\W*%(quote)s[^%(delim)s\n]*%(quote)s[^%(delim)s\n]*%(quote)s\W*((%(delim)s)|$)" % \
-                               {'delim':re.escape(delim), 'quote':quotechar}, re.MULTILINE)
-
-
-
-        if dq_regexp.search(data):
-            doublequote = True
-        else:
-            doublequote = False
+        # A doubled quote character inside a quoted field means
+        # a double quoted format.  Match whole fields, so that a match
+        # cannot slide across field boundaries.
+        doublequote = False
+        if delim:
+            dq_regexp = re.compile(
+                    r"(?:(?<=%(delim)s)|^)%(space)s%(quote)s"     # ,"
+                    r"((?:%(quote)s%(quote)s|[^%(quote)s]++)*+)"  # the body
+                    r"%(quote)s(?:%(delim)s|$)"                   # ",
+                    % {'delim': re.escape(delim), 'quote': quotechar,
+                       # Skipping spaces after a space rescans them.
+                       'space': ' *+' if delim != ' ' else ''},
+                    re.MULTILINE)
+            dquotechar = quotechar * 2
+            doublequote = any(dquotechar in m[1]
+                              for m in dq_regexp.finditer(data))
 
         return (quotechar, doublequote, delim, skipinitialspace)
 

Lib/ensurepip/__init__.py

@@ -10,7 +10,7 @@
 
 
 __all__ = ["version", "bootstrap"]
-_PIP_VERSION = "26.1.2"
+_PIP_VERSION = "26.2"
 
 # Directory of system wheel packages. Some Linux distribution packaging
 # policies recommend against bundling dependencies. For example, Fedora

…pip/_bundled/pip-26.1.2-py3-none-any.whl …repip/_bundled/pip-26.2-py3-none-any.whlLib/ensurepip/_bundled/pip-26.1.2-py3-none-any.whl renamed to Lib/ensurepip/_bundled/pip-26.2-py3-none-any.whl Lib/ensurepip/_bundled/pip-26.1.2-py3-none-any.whl renamed to Lib/ensurepip/_bundled/pip-26.2-py3-none-any.whl

@@ -1501,6 +1501,50 @@ def test_doublequote(self):
         dialect = sniffer.sniff(self.sample9)
         self.assertTrue(dialect.doublequote)
 
+    def test_sniff_regex_backtracking(self):
+        # gh-109638: this artificial sample used to take minutes.
+        sniffer = csv.Sniffer()
+        sample = '"",' * 100 + '"' * 100 + '0' + '"' * 100 + '0'
+        self.assertEqual(sniffer.sniff(sample).delimiter, ',')
+
+    def test_sniff_doublequote_across_fields(self):
+        # A quoted field which contains the delimiter, followed by
+        # an empty quoted field, is not a doubled quote.
+        sniffer = csv.Sniffer()
+        sample = '",","",","\n' * 4
+        dialect = sniffer.sniff(sample)
+        self.assertEqual(dialect.delimiter, ',')
+        self.assertEqual(dialect.quotechar, '"')
+        self.assertIs(dialect.doublequote, False)
+        self.assertEqual(next(csv.reader(StringIO(sample), dialect)),
+                         [',', '', ','])
+
+    def test_sniff_doublequote_record_separators(self):
+        # The record separator ends a field as a delimiter does.
+        sniffer = csv.Sniffer()
+        for sep in '\n', '\r\n', '\r':
+            with self.subTest(sep=sep):
+                sample = ('x,"a""b"' + sep + 'y,"c"' + sep) * 2
+                self.assertIs(sniffer.sniff(sample).doublequote, True)
+                sample = ('"",","' + sep) * 4
+                self.assertIs(sniffer.sniff(sample).doublequote, False)
+
+    def test_sniff_single_column(self):
+        # This sample used to be quadratic.
+        sniffer = csv.Sniffer()
+        sample = '"a"\n' + ' ' * 100000
+        with self.assertRaisesRegex(csv.Error, "Could not determine delimiter"):
+            sniffer.sniff(sample, delimiters=',;')
+
+    def test_sniff_space_delimiter(self):
+        # This sample used to be quadratic.
+        sniffer = csv.Sniffer()
+        sample = '"a" "b"\n' + ' ' * 100000
+        dialect = sniffer.sniff(sample)
+        self.assertEqual(dialect.delimiter, ' ')
+        self.assertIs(dialect.doublequote, False)
+
+
 class NUL:
     def write(s, *args):
         pass

Lib/test/test_csv.py

@@ -956,6 +956,13 @@ def test_parent_parser_outlives_its_subparsers__chain(self):
         del parser
         del subparser
 
+    def test_subparser_inherits_reparse_deferral(self):
+        for enabled in (True, False):
+            parser = expat.ParserCreate()
+            parser.SetReparseDeferralEnabled(enabled)
+            subparser = parser.ExternalEntityParserCreate(None)
+            self.assertEqual(subparser.GetReparseDeferralEnabled(), enabled)
+
 
 class ExternalEntityParserCreateErrorTest(unittest.TestCase):
     """ExternalEntityParserCreate error paths should not crash or leak

Lib/test/test_pyexpat.py

@@ -54,7 +54,11 @@ def test_eval_null_in_result(self):
 
     def test_eval_surrogates_in_result(self):
         tcl = self.interp
-        self.assertEqual(tcl.eval(r'set a "<\ud83d\udcbb>"'), '<\U0001f4bb>')
+        result = tcl.eval(r'set a "<\ud83d\udcbb>"')
+        if sys.platform == 'win32' and tcl_version >= (9, 0):
+            self.assertEqual('<\ud83d\udcbb>', result)
+        else:
+            self.assertEqual('<\U0001f4bb>', result)
 
     def testEvalException(self):
         tcl = self.interp
@@ -289,7 +293,11 @@ def test_evalfile_surrogates_in_result(self):
             set b "<\\ud83d\\udcbb>"
             """)
         tcl.evalfile(filename)
-        self.assertEqual(tcl.eval('set b'), '<\U0001f4bb>')
+        result = tcl.eval('set b')
+        if sys.platform == 'win32' and tcl_version >= (9, 0):
+            self.assertEqual('<\ud83d\udcbb>', result)
+        else:
+            self.assertEqual('<\U0001f4bb>', result)
 
     def testEvalFileException(self):
         tcl = self.interp

Lib/test/test_tcl.py

@@ -280,6 +280,7 @@ DIST=		$(DISTFILES) $(DISTDIRS)
 LIBRARY=	@LIBRARY@
 LDLIBRARY=      @LDLIBRARY@
 BLDLIBRARY=     @BLDLIBRARY@
+MODULE_LDFLAGS_SHARED=$(if $(LIBPYTHON),$(BLDLIBRARY))
 PY3LIBRARY=     @PY3LIBRARY@
 DLLLIBRARY=	@DLLLIBRARY@
 LDLIBRARYDIR=   @LDLIBRARYDIR@

Makefile.pre.in

@@ -0,0 +1 @@
+Fix library name in python3.pc on Android.

Misc/NEWS.d/next/Build/2026-03-07-02-09-57.gh-issue-138800.VD8qbz.rst

@@ -0,0 +1,3 @@
+Fix :meth:`!ExternalEntityParserCreate` not propagating the reparse-deferral
+setting to the subparser, which left :meth:`!GetReparseDeferralEnabled`
+returning an uninitialized value.  Patch by tonghuaroot.

Misc/NEWS.d/next/Library/2026-07-26-00-00-00.gh-issue-154738.Rd5Pxe.rst

@@ -0,0 +1,3 @@
+Fix exponential time in :meth:`csv.Sniffer.sniff` for a sample which contains
+many quote characters.  A doubled quote character is now also detected in
+a field which contains the delimiter or a line break.