[3.11] gh-98930: improve the docstring of signal.strsignal (GH-99290) (#99449)

Improves the docstring on signal.strsignal to make it explain when it returns a message, None, or when it raises ValueError.

Closes GH-98930

Co-authored-by: Gregory P. Smith <greg@krypto.org>.
(cherry picked from commit 88385b8564)

Co-authored-by: ram vikram singh <ramvikrams243@gmail.com>

Doc/library/signal.rst

@@ -362,9 +362,9 @@ The :mod:`signal` module defines the following functions:
 
 .. function:: strsignal(signalnum)
 
-   Return the system description of the signal *signalnum*, such as
-   "Interrupt", "Segmentation fault", etc. Returns :const:`None` if the signal
-   is not recognized.
+   Returns the description of signal *signalnum*, such as "Interrupt"
+   for :const:`SIGINT`. Returns :const:`None` if *signalnum* has no
+   description. Raises :exc:`ValueError` if *signalnum* is invalid.
 
    .. versionadded:: 3.8
 

Lib/ctypes/test/test_struct_fields.py

@@ -54,6 +54,15 @@ class X(Structure):
         x.char = b'a\0b\0'
         self.assertEqual(bytes(x), b'a\x00###')
 
+    def test_gh99275(self):
+        class BrokenStructure(Structure):
+            def __init_subclass__(cls, **kwargs):
+                cls._fields_ = []  # This line will fail, `stgdict` is not ready
+
+        with self.assertRaisesRegex(TypeError,
+                                    'ctypes state is not initialized'):
+            class Subclass(BrokenStructure): ...
+
     # __set__ and __get__ should raise a TypeError in case their self
     # argument is not a ctype instance.
     def test___set__(self):

Lib/test/test_urlparse.py

@@ -668,6 +668,24 @@ def test_attributes_bad_port(self):
                         with self.assertRaises(ValueError):
                             p.port
 
+    def test_attributes_bad_scheme(self):
+        """Check handling of invalid schemes."""
+        for bytes in (False, True):
+            for parse in (urllib.parse.urlsplit, urllib.parse.urlparse):
+                for scheme in (".", "+", "-", "0", "http&", "६http"):
+                    with self.subTest(bytes=bytes, parse=parse, scheme=scheme):
+                        url = scheme + "://www.example.net"
+                        if bytes:
+                            if url.isascii():
+                                url = url.encode("ascii")
+                            else:
+                                continue
+                        p = parse(url)
+                        if bytes:
+                            self.assertEqual(p.scheme, b"")
+                        else:
+                            self.assertEqual(p.scheme, "")
+
     def test_attributes_without_netloc(self):
         # This example is straight from RFC 3261.  It looks like it
         # should allow the username, hostname, and port to be filled

Lib/urllib/parse.py

@@ -460,7 +460,7 @@ def urlsplit(url, scheme='', allow_fragments=True):
     allow_fragments = bool(allow_fragments)
     netloc = query = fragment = ''
     i = url.find(':')
-    if i > 0:
+    if i > 0 and url[0].isascii() and url[0].isalpha():
         for c in url[:i]:
             if c not in scheme_chars:
                 break

Makefile.pre.in

@@ -2528,12 +2528,12 @@ Python/thread.o: @THREADHEADERS@ $(srcdir)/Python/condvar.h
 
 MODULE_CMATH_DEPS=$(srcdir)/Modules/_math.h
 MODULE_MATH_DEPS=$(srcdir)/Modules/_math.h
-MODULE_PYEXPAT_DEPS=$(LIBEXPAT_HEADERS) @LIBEXPAT_INTERNAL@
+MODULE_PYEXPAT_DEPS=@LIBEXPAT_INTERNAL@
 MODULE_UNICODEDATA_DEPS=$(srcdir)/Modules/unicodedata_db.h $(srcdir)/Modules/unicodename_db.h
 MODULE__BLAKE2_DEPS=$(srcdir)/Modules/_blake2/impl/blake2-config.h $(srcdir)/Modules/_blake2/impl/blake2-impl.h $(srcdir)/Modules/_blake2/impl/blake2.h $(srcdir)/Modules/_blake2/impl/blake2b-load-sse2.h $(srcdir)/Modules/_blake2/impl/blake2b-load-sse41.h $(srcdir)/Modules/_blake2/impl/blake2b-ref.c $(srcdir)/Modules/_blake2/impl/blake2b-round.h $(srcdir)/Modules/_blake2/impl/blake2b.c $(srcdir)/Modules/_blake2/impl/blake2s-load-sse2.h $(srcdir)/Modules/_blake2/impl/blake2s-load-sse41.h $(srcdir)/Modules/_blake2/impl/blake2s-load-xop.h $(srcdir)/Modules/_blake2/impl/blake2s-ref.c $(srcdir)/Modules/_blake2/impl/blake2s-round.h $(srcdir)/Modules/_blake2/impl/blake2s.c $(srcdir)/Modules/_blake2/blake2module.h $(srcdir)/Modules/hashlib.h
 MODULE__CTYPES_DEPS=$(srcdir)/Modules/_ctypes/ctypes.h
-MODULE__DECIMAL_DEPS=$(srcdir)/Modules/_decimal/docstrings.h $(LIBMPDEC_HEADERS) @LIBMPDEC_INTERNAL@
-MODULE__ELEMENTTREE_DEPS=$(srcdir)/Modules/pyexpat.c $(LIBEXPAT_HEADERS) @LIBEXPAT_INTERNAL@
+MODULE__DECIMAL_DEPS=$(srcdir)/Modules/_decimal/docstrings.h @LIBMPDEC_INTERNAL@
+MODULE__ELEMENTTREE_DEPS=$(srcdir)/Modules/pyexpat.c @LIBEXPAT_INTERNAL@
 MODULE__HASHLIB_DEPS=$(srcdir)/Modules/hashlib.h
 MODULE__IO_DEPS=$(srcdir)/Modules/_io/_iomodule.h
 MODULE__MD5_DEPS=$(srcdir)/Modules/hashlib.h

Misc/NEWS.d/next/Build/2022-10-26-12-37-52.gh-issue-98707.eVXGEx.rst

@@ -0,0 +1,4 @@
+Don't use vendored ``libmpdec`` headers if :option:`--with-system-libmpdec`
+is passed to :program:`configure`.
+Don't use vendored ``libexpat`` headers if :option:`--with-system-expat`
+is passed to :program:`!configure`.

Misc/NEWS.d/next/Library/2022-11-09-12-16-35.gh-issue-99275.klOqoL.rst

@@ -0,0 +1,2 @@
+Fix ``SystemError`` in :mod:`ctypes` when exception was not set during
+``__initsubclass__``.

Misc/NEWS.d/next/Library/2022-11-12-15-45-51.gh-issue-99418.FxfAXS.rst

@@ -0,0 +1,2 @@
+Fix bug in :func:`urllib.parse.urlparse` that causes URL schemes that begin
+with a digit, a plus sign, or a minus sign to be parsed incorrectly.

Modules/_ctypes/stgdict.c

@@ -430,8 +430,11 @@ PyCStructUnionType_update_stgdict(PyObject *type, PyObject *fields, int isStruct
     }
 
     stgdict = PyType_stgdict(type);
-    if (!stgdict)
+    if (!stgdict) {
+        PyErr_SetString(PyExc_TypeError,
+                        "ctypes state is not initialized");
         return -1;
+    }
     /* If this structure/union is already marked final we cannot assign
        _fields_ anymore. */
 

Modules/clinic/signalmodule.c.h

@@ -205,8 +205,9 @@ PyDoc_STRVAR(signal_strsignal__doc__,
 "\n"
 "Return the system description of the given signal.\n"
 "\n"
-"The return values can be such as \"Interrupt\", \"Segmentation fault\", etc.\n"
-"Returns None if the signal is not recognized.");
+"Returns the description of signal *signalnum*, such as \"Interrupt\"\n"
+"for :const:`SIGINT`. Returns :const:`None` if *signalnum* has no\n"
+"description. Raises :exc:`ValueError` if *signalnum* is invalid.");
 
 #define SIGNAL_STRSIGNAL_METHODDEF    \
     {"strsignal", (PyCFunction)signal_strsignal, METH_O, signal_strsignal__doc__},
@@ -698,4 +699,4 @@ exit:
 #ifndef SIGNAL_PIDFD_SEND_SIGNAL_METHODDEF
     #define SIGNAL_PIDFD_SEND_SIGNAL_METHODDEF
 #endif /* !defined(SIGNAL_PIDFD_SEND_SIGNAL_METHODDEF) */
-/*[clinic end generated code: output=6ca1b70310eecdba input=a9049054013a1b77]*/
+/*[clinic end generated code: output=9b3f9f1ae2ac2b94 input=a9049054013a1b77]*/

Modules/signalmodule.c

@@ -627,13 +627,14 @@ signal.strsignal
 
 Return the system description of the given signal.
 
-The return values can be such as "Interrupt", "Segmentation fault", etc.
-Returns None if the signal is not recognized.
+Returns the description of signal *signalnum*, such as "Interrupt"
+for :const:`SIGINT`. Returns :const:`None` if *signalnum* has no
+description. Raises :exc:`ValueError` if *signalnum* is invalid.
 [clinic start generated code]*/
 
 static PyObject *
 signal_strsignal_impl(PyObject *module, int signalnum)
-/*[clinic end generated code: output=44e12e1e3b666261 input=b77914b03f856c74]*/
+/*[clinic end generated code: output=44e12e1e3b666261 input=238b335847778bc0]*/
 {
     const char *res;
 

configure

@@ -12110,7 +12110,7 @@ else
 
   LIBEXPAT_CFLAGS="-I\$(srcdir)/Modules/expat"
   LIBEXPAT_LDFLAGS="-lm \$(LIBEXPAT_A)"
-  LIBEXPAT_INTERNAL="\$(LIBEXPAT_A)"
+  LIBEXPAT_INTERNAL="\$(LIBEXPAT_HEADERS) \$(LIBEXPAT_A)"
 
 fi
 
@@ -12184,7 +12184,7 @@ else
 
   LIBMPDEC_CFLAGS="-I\$(srcdir)/Modules/_decimal/libmpdec"
   LIBMPDEC_LDFLAGS="-lm \$(LIBMPDEC_A)"
-  LIBMPDEC_INTERNAL="\$(LIBMPDEC_A)"
+  LIBMPDEC_INTERNAL="\$(LIBMPDEC_HEADERS) \$(LIBMPDEC_A)"
 
     if test "x$with_pydebug" = xyes; then :
 

configure.ac

@@ -3610,7 +3610,7 @@ AS_VAR_IF([with_system_expat], [yes], [
 ], [
   LIBEXPAT_CFLAGS="-I\$(srcdir)/Modules/expat"
   LIBEXPAT_LDFLAGS="-lm \$(LIBEXPAT_A)"
-  LIBEXPAT_INTERNAL="\$(LIBEXPAT_A)"
+  LIBEXPAT_INTERNAL="\$(LIBEXPAT_HEADERS) \$(LIBEXPAT_A)"
 ])
 
 AC_SUBST([LIBEXPAT_CFLAGS])
@@ -3666,7 +3666,7 @@ AS_VAR_IF([with_system_libmpdec], [yes], [
 ], [
   LIBMPDEC_CFLAGS="-I\$(srcdir)/Modules/_decimal/libmpdec"
   LIBMPDEC_LDFLAGS="-lm \$(LIBMPDEC_A)"
-  LIBMPDEC_INTERNAL="\$(LIBMPDEC_A)"
+  LIBMPDEC_INTERNAL="\$(LIBMPDEC_HEADERS) \$(LIBMPDEC_A)"
 
   dnl Disable forced inlining in debug builds, see GH-94847
   AS_VAR_IF([with_pydebug], [yes], [