gh-150626: Update "Format String Syntax" documentation block to match actual behaviour

.github/workflows/jit.yml

@@ -64,10 +64,10 @@ jobs:
         include:
           - target: i686-pc-windows-msvc/msvc
             architecture: Win32
-            runner: windows-2025-vs2026
+            runner: windows-2025
           - target: x86_64-pc-windows-msvc/msvc
             architecture: x64
-            runner: windows-2025-vs2026
+            runner: windows-2025
           - target: aarch64-pc-windows-msvc/msvc
             architecture: ARM64
             runner: windows-11-arm
@@ -183,6 +183,9 @@ jobs:
           - name: JIT without optimizations (Debug)
             configure_flags: --enable-experimental-jit --with-pydebug
             test_env: "PYTHON_UOPS_OPTIMIZE=0"
+          - name: JIT with stress testing (Debug)
+            configure_flags: --enable-experimental-jit --with-pydebug
+            test_env: "PYTHON_JIT_STRESS=1"
           - name: JIT with tail calling interpreter
             configure_flags: --enable-experimental-jit --with-tail-call-interp --with-pydebug
             use_clang: true

.github/workflows/reusable-windows-msi.yml

@@ -17,7 +17,7 @@ env:
 jobs:
   build:
     name: installer for ${{ inputs.arch }}
-    runs-on: ${{ inputs.arch == 'arm64' && 'windows-11-arm' || 'windows-2025-vs2026' }}
+    runs-on: ${{ inputs.arch == 'arm64' && 'windows-11-arm' || 'windows-2025' }}
     timeout-minutes: 60
     env:
       ARCH: ${{ inputs.arch }}

.github/workflows/reusable-windows.yml

@@ -26,7 +26,7 @@ env:
 jobs:
   build:
     name: Build and test (${{ inputs.arch }}, ${{ inputs.interpreter }})
-    runs-on: ${{ inputs.arch == 'arm64' && 'windows-11-arm' || 'windows-2025-vs2026' }}
+    runs-on: ${{ inputs.arch == 'arm64' && 'windows-11-arm' || 'windows-2025' }}
     timeout-minutes: 60
     env:
       ARCH: ${{ inputs.arch }}

.readthedocs.yml

@@ -11,19 +11,21 @@ build:
   os: ubuntu-24.04
   tools:
     python: "3"
+  apt_packages:
+    - jq
 
   jobs:
-    post_checkout:
+    post_system_dependencies:
       # https://docs.readthedocs.com/platform/stable/guides/build/skip-build.html#skip-builds-based-on-conditions
       #
-      # Cancel building pull requests when there aren't changes in the Doc
+      # Cancel building pull requests when there are no changes in the Doc
       # directory or RTD configuration, or if we can't cleanly merge the base
       # branch.
       - |
         set -eEux;
         if [ "$READTHEDOCS_VERSION_TYPE" = "external" ];
         then
-          base_branch=main;
+          base_branch=$(wget -qO- "https://api.github.com/repos/python/cpython/pulls/$READTHEDOCS_VERSION" | jq -er ".base.ref");
           git fetch --depth=50 origin $base_branch:origin-$base_branch;
           for attempt in $(seq 10);
           do

Doc/c-api/bytes.rst

@@ -384,14 +384,18 @@ Getters
 
    Get the writer size.
 
+   The function does not invalidate pointers returned by
+   :c:func:`PyBytesWriter_GetData`.
+
    The function cannot fail.
 
 .. c:function:: void* PyBytesWriter_GetData(PyBytesWriter *writer)
 
    Get the writer data: start of the internal buffer.
 
-   The pointer is valid until :c:func:`PyBytesWriter_Finish` or
-   :c:func:`PyBytesWriter_Discard` is called on *writer*.
+   The pointer remains valid until a :c:type:`PyBytesWriter` function other
+   than :c:func:`PyBytesWriter_GetData` or :c:func:`PyBytesWriter_GetSize` is
+   called on *writer*.
 
    The function cannot fail.
 

Doc/deprecations/index.rst

@@ -1,8 +1,6 @@
 Deprecations
 ============
 
-.. include:: pending-removal-in-3.16.rst
-
 .. include:: pending-removal-in-3.17.rst
 
 .. include:: pending-removal-in-3.18.rst
@@ -20,8 +18,6 @@ Deprecations
 C API deprecations
 ------------------
 
-.. include:: c-api-pending-removal-in-3.16.rst
-
 .. include:: c-api-pending-removal-in-3.18.rst
 
 .. include:: c-api-pending-removal-in-3.19.rst

Doc/extending/extending.rst

@@ -231,10 +231,8 @@ calling the Python callback functions from a C callback.  Other uses are also
 imaginable.
 
 Fortunately, the Python interpreter is easily called recursively, and there is a
-standard interface to call a Python function.  (I won't dwell on how to call the
-Python parser with a particular string as input --- if you're interested, have a
-look at the implementation of the :option:`-c` command line option in
-:file:`Modules/main.c` from the Python source code.)
+standard interface to call a Python function.  (If you're interested in how to call the
+Python parser with a particular string as input, see :ref:`veryhigh`.)
 
 Calling a Python function is easy.  First, the Python program must somehow pass
 you the Python function object.  You should provide a function (or some other
@@ -641,7 +639,7 @@ and the object is freed.
 
 An alternative strategy is called :dfn:`automatic garbage collection`.
 (Sometimes, reference counting is also referred to as a garbage collection
-strategy, hence my use of "automatic" to distinguish the two.)  The big
+strategy, hence the use of "automatic" to distinguish the two.)  The big
 advantage of automatic garbage collection is that the user doesn't need to call
 :c:func:`free` explicitly.  (Another claimed advantage is an improvement in speed
 or memory usage --- this is no hard fact however.)  The disadvantage is that for

Doc/glossary.rst

@@ -96,21 +96,24 @@ Glossary
       :meth:`~object.__aexit__` methods.  Introduced by :pep:`492`.
 
    asynchronous generator
-      A function which returns an :term:`asynchronous generator iterator`.  It
-      looks like a coroutine function defined with :keyword:`async def` except
-      that it contains :keyword:`yield` expressions for producing a series of
-      values usable in an :keyword:`async for` loop.
-
-      Usually refers to an asynchronous generator function, but may refer to an
-      *asynchronous generator iterator* in some contexts.  In cases where the
-      intended meaning isn't clear, using the full terms avoids ambiguity.
+      Informally used to mean either an :term:`asynchronous generator
+      function` or an :term:`asynchronous generator iterator`, depending on
+      context.  The formal terms :term:`asynchronous generator function` and
+      :term:`asynchronous generator iterator` are uncommon in practice;
+      "asynchronous generator" alone is almost always sufficient.
+
+   asynchronous generator function
+      A function which returns an :term:`asynchronous generator iterator`.
+      It looks like a coroutine function defined with :keyword:`async def`
+      except that it contains :keyword:`yield` expressions for producing a
+      series of values usable in an :keyword:`async for` loop.  See :pep:`525`.
 
       An asynchronous generator function may contain :keyword:`await`
       expressions as well as :keyword:`async for`, and :keyword:`async with`
       statements.
 
    asynchronous generator iterator
-      An object created by an :term:`asynchronous generator` function.
+      An object created by an :term:`asynchronous generator function`.
 
       This is an :term:`asynchronous iterator` which when called using the
       :meth:`~object.__anext__` method returns an awaitable object which will execute
@@ -641,23 +644,33 @@ Glossary
       .. index:: single: generator
 
    generator
-      A function which returns a :term:`generator iterator`.  It looks like a
-      normal function except that it contains :keyword:`yield` expressions
-      for producing a series of values usable in a for-loop or that can be
-      retrieved one at a time with the :func:`next` function.
+      Informally used to mean either a :term:`generator function` or a
+      :term:`generator iterator`, depending on context.  The formal terms
+      :term:`generator function` and :term:`generator iterator` are uncommon
+      in practice; "generator" alone is almost always sufficient.
 
-      Usually refers to a generator function, but may refer to a
-      *generator iterator* in some contexts.  In cases where the intended
-      meaning isn't clear, using the full terms avoids ambiguity.
+      .. index:: single: generator function
+
+   generator function
+      A function which returns a :term:`generator` object.  It looks like a
+      normal function except that it contains :keyword:`yield` expressions
+      for producing a series of values usable in a :keyword:`for`\-loop or
+      that can be retrieved one at a time with the :func:`next` function.
+      See :ref:`yieldexpr`.
 
    generator iterator
-      An object created by a :term:`generator` function.
+      An object created by a :term:`generator function` or a
+      :term:`generator expression`.
 
       Each :keyword:`yield` temporarily suspends processing, remembering the
-      execution state (including local variables and pending
-      try-statements).  When the *generator iterator* resumes, it picks up where
-      it left off (in contrast to functions which start fresh on every
-      invocation).
+      execution state (including local variables and pending try-statements).
+      When the *generator iterator* resumes, it picks up where it left off
+      (in contrast to functions which start fresh on every invocation).
+
+      Generator iterators also implement the :meth:`~generator.send` method
+      to send a value into the suspended generator, and the
+      :meth:`~generator.throw` method to raise an exception at the point
+      where the generator was paused.  See :ref:`generator-methods`.
 
       .. index:: single: generator expression
 

Doc/library/codecs.rst

@@ -1399,6 +1399,14 @@ encodings.
 | punycode           |         | Implement :rfc:`3492`.    |
 |                    |         | Stateful codecs are not   |
 |                    |         | supported.                |
+|                    |         |                           |
+|                    |         | .. warning::              |
+|                    |         |                           |
+|                    |         |    The decoding and       |
+|                    |         |    encoding algorithms    |
+|                    |         |    scale poorly, so       |
+|                    |         |    limit the length of    |
+|                    |         |    untrusted input.       |
 +--------------------+---------+---------------------------+
 | raw_unicode_escape |         | Latin-1 encoding with     |
 |                    |         | :samp:`\\u{XXXX}` and     |

Doc/library/csv.rst

@@ -81,6 +81,13 @@ The :mod:`!csv` module defines the following functions:
       Spam, Spam, Spam, Spam, Spam, Baked Beans
       Spam, Lovely Spam, Wonderful Spam
 
+   where :file:`eggs.csv` contains:
+
+   .. code-block:: text
+
+      Spam Spam Spam Spam Spam |Baked Beans|
+      Spam |Lovely Spam| |Wonderful Spam|
+
 
 .. function:: writer(csvfile, /, dialect='excel', **fmtparams)
 
@@ -110,6 +117,13 @@ The :mod:`!csv` module defines the following functions:
           spamwriter.writerow(['Spam'] * 5 + ['Baked Beans'])
           spamwriter.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])
 
+   which writes :file:`eggs.csv` containing:
+
+   .. code-block:: text
+
+      Spam Spam Spam Spam Spam |Baked Beans|
+      Spam |Lovely Spam| |Wonderful Spam|
+
 
 .. function:: register_dialect(name, /, dialect='excel', **fmtparams)
 
@@ -191,6 +205,14 @@ The :mod:`!csv` module defines the following classes:
        >>> print(row)
        {'first_name': 'John', 'last_name': 'Cleese'}
 
+   where :file:`names.csv` contains:
+
+   .. code-block:: text
+
+      first_name,last_name
+      Eric,Idle
+      John,Cleese
+
 
 .. class:: DictWriter(f, fieldnames, restval='', extrasaction='raise', \
                       dialect='excel', *args, **kwds)
@@ -228,6 +250,15 @@ The :mod:`!csv` module defines the following classes:
            writer.writerow({'first_name': 'Lovely', 'last_name': 'Spam'})
            writer.writerow({'first_name': 'Wonderful', 'last_name': 'Spam'})
 
+   which writes :file:`names.csv` containing:
+
+   .. code-block:: text
+
+      first_name,last_name
+      Baked,Beans
+      Lovely,Spam
+      Wonderful,Spam
+
 
 .. class:: Dialect
 

Doc/library/curses.ascii.rst

@@ -114,7 +114,7 @@ C library:
 
 .. function:: isblank(c)
 
-   Checks for an ASCII whitespace character; space or horizontal tab.
+   Checks for an ASCII blank character; space or horizontal tab.
 
 
 .. function:: iscntrl(c)
@@ -168,7 +168,8 @@ C library:
 
 .. function:: isctrl(c)
 
-   Checks for an ASCII control character (ordinal values 0 to 31).
+   Checks for an ASCII control character (ordinal values 0 to 31).  Unlike
+   :func:`iscntrl`, this does not include the delete character (0x7f).
 
 
 .. function:: ismeta(c)

Doc/library/curses.panel.rst

@@ -26,7 +26,8 @@ The module :mod:`!curses.panel` defines the following functions:
 
 .. function:: new_panel(win)
 
-   Returns a panel object, associating it with the given window *win*. Be aware
+   Returns a panel object, associating it with the given window *win* and
+   placing the new panel on top of the panel stack.  Be aware
    that you need to keep the returned panel object referenced explicitly.  If you
    don't, the panel object is garbage collected and removed from the panel stack.
 
@@ -44,7 +45,7 @@ The module :mod:`!curses.panel` defines the following functions:
 
 .. _curses-panel-objects:
 
-Panel Objects
+Panel objects
 -------------
 
 Panel objects, as returned by :func:`new_panel` above, are windows with a
@@ -99,7 +100,8 @@ Panel objects have the following methods:
 
 .. method:: Panel.show()
 
-   Display the panel (which might have been hidden).
+   Display the panel (which might have been hidden), placing it on top of
+   the panel stack.
 
 
 .. method:: Panel.top()