Merge 'origin/main' into gh-116738-bisect-threadsafe-doc

Author: nascheme

Doc/library/array.rst

@@ -24,7 +24,7 @@ defined:
 +-----------+--------------------+-------------------+-----------------------+-------+
 | ``'u'``   | wchar_t            | Unicode character | 2                     | \(1)  |
 +-----------+--------------------+-------------------+-----------------------+-------+
-| ``'w'``   | Py_UCS4            | Unicode character | 4                     |       |
+| ``'w'``   | Py_UCS4            | Unicode character | 4                     | \(2)  |
 +-----------+--------------------+-------------------+-----------------------+-------+
 | ``'h'``   | signed short       | int               | 2                     |       |
 +-----------+--------------------+-------------------+-----------------------+-------+
@@ -60,6 +60,9 @@ Notes:
    .. deprecated-removed:: 3.3 3.16
       Please migrate to ``'w'`` typecode.
 
+(2)
+   .. versionadded:: 3.13
+
 
 The actual representation of values is determined by the machine architecture
 (strictly speaking, by the C implementation).  The actual size can be accessed

Doc/library/asyncio-eventloop.rst

@@ -611,6 +611,12 @@ Opening network connections
      to bind the socket locally.  The *local_host* and *local_port*
      are looked up using :meth:`getaddrinfo`.
 
+     .. note::
+
+        On Windows, when using the proactor event loop with ``local_addr=None``,
+        an :exc:`OSError` with :attr:`!errno.WSAEINVAL` will be raised
+        when running it.
+
    * *remote_addr*, if given, is a ``(remote_host, remote_port)`` tuple used
      to connect the socket to a remote address.  The *remote_host* and
      *remote_port* are looked up using :meth:`getaddrinfo`.

Doc/library/asyncio-queue.rst

@@ -102,17 +102,34 @@ Queue
 
    .. method:: shutdown(immediate=False)
 
-      Shut down the queue, making :meth:`~Queue.get` and :meth:`~Queue.put`
+      Put a :class:`Queue` instance into a shutdown mode.
+
+      The queue can no longer grow.
+      Future calls to :meth:`~Queue.put` raise :exc:`QueueShutDown`.
+      Currently blocked callers of :meth:`~Queue.put` will be unblocked
+      and will raise :exc:`QueueShutDown` in the formerly blocked thread.
+
+      If *immediate* is false (the default), the queue can be wound
+      down normally with :meth:`~Queue.get` calls to extract tasks
+      that have already been loaded.
+
+      And if :meth:`~Queue.task_done` is called for each remaining task, a
+      pending :meth:`~Queue.join` will be unblocked normally.
+
+      Once the queue is empty, future calls to :meth:`~Queue.get` will
       raise :exc:`QueueShutDown`.
 
-      By default, :meth:`~Queue.get` on a shut down queue will only
-      raise once the queue is empty. Set *immediate* to true to make
-      :meth:`~Queue.get` raise immediately instead.
+      If *immediate* is true, the queue is terminated immediately.
+      The queue is drained to be completely empty and the count
+      of unfinished tasks is reduced by the number of tasks drained.
+      If unfinished tasks is zero, callers of :meth:`~Queue.join`
+      are unblocked.  Also, blocked callers of :meth:`~Queue.get`
+      are unblocked and will raise :exc:`QueueShutDown` because the
+      queue is empty.
 
-      All blocked callers of :meth:`~Queue.put` and :meth:`~Queue.get`
-      will be unblocked. If *immediate* is true, a task will be marked
-      as done for each remaining item in the queue, which may unblock
-      callers of :meth:`~Queue.join`.
+      Use caution when using :meth:`~Queue.join` with *immediate* set
+      to true. This unblocks the join even when no work has been done
+      on the tasks, violating the usual invariant for joining a queue.
 
       .. versionadded:: 3.13
 
@@ -129,9 +146,6 @@ Queue
       call was received for every item that had been :meth:`~Queue.put`
       into the queue).
 
-      ``shutdown(immediate=True)`` calls :meth:`task_done` for each
-      remaining item in the queue.
-
       Raises :exc:`ValueError` if called more times than there were
       items placed in the queue.
 

Doc/library/bdb.rst

@@ -192,12 +192,8 @@ The :mod:`bdb` module also defines two classes:
         entered.
       * ``"return"``: A function or other code block is about to return.
       * ``"exception"``: An exception has occurred.
-      * ``"c_call"``: A C function is about to be called.
-      * ``"c_return"``: A C function has returned.
-      * ``"c_exception"``: A C function has raised an exception.
 
-      For the Python events, specialized functions (see below) are called.  For
-      the C events, no action is taken.
+      For all the events, specialized functions (see below) are called.
 
       The *arg* parameter depends on the previous event.
 

Doc/library/codecs.rst

@@ -1483,6 +1483,36 @@ to :class:`bytes` mappings. They are not supported by :meth:`bytes.decode`
    Restoration of the aliases for the binary transforms.
 
 
+.. _standalone-codec-functions:
+
+Standalone Codec Functions
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The following functions provide encoding and decoding functionality similar to codecs,
+but are not available as named codecs through :func:`codecs.encode` or :func:`codecs.decode`.
+They are used internally (for example, by :mod:`pickle`) and behave similarly to the
+``string_escape`` codec that was removed in Python 3.
+
+.. function:: codecs.escape_encode(input, errors=None)
+
+   Encode *input* using escape sequences. Similar to how :func:`repr` on bytes
+   produces escaped byte values.
+
+   *input* must be a :class:`bytes` object.
+
+   Returns a tuple ``(output, length)`` where *output* is a :class:`bytes`
+   object and *length* is the number of bytes consumed.
+
+.. function:: codecs.escape_decode(input, errors=None)
+
+   Decode *input* from escape sequences back to the original bytes.
+
+   *input* must be a :term:`bytes-like object`.
+
+   Returns a tuple ``(output, length)`` where *output* is a :class:`bytes`
+   object and *length* is the number of bytes consumed.
+
+
 .. _text-transforms:
 
 Text Transforms

Doc/library/concurrent.futures.rst

@@ -342,6 +342,11 @@ that :class:`ProcessPoolExecutor` will not work in the interactive interpreter.
 Calling :class:`Executor` or :class:`Future` methods from a callable submitted
 to a :class:`ProcessPoolExecutor` will result in deadlock.
 
+Note that the restrictions on functions and arguments needing to picklable as
+per :class:`multiprocessing.Process` apply when using :meth:`~Executor.submit`
+and :meth:`~Executor.map` on a :class:`ProcessPoolExecutor`. A function defined
+in a REPL or a lambda should not be expected to work.
+
 .. class:: ProcessPoolExecutor(max_workers=None, mp_context=None, initializer=None, initargs=(), max_tasks_per_child=None)
 
    An :class:`Executor` subclass that executes calls asynchronously using a pool

Doc/library/concurrent.interpreters.rst

@@ -134,7 +134,7 @@ makes them similar to processes, but they still enjoy in-process
 efficiency, like threads.
 
 All that said, interpreters do naturally support certain flavors of
-concurrency, as a powerful side effect of that isolation.
+concurrency.
 There's a powerful side effect of that isolation.  It enables a
 different approach to concurrency than you can take with async or
 threads.  It's a similar concurrency model to CSP or the actor model,

Doc/library/http.cookies.rst

@@ -148,9 +148,12 @@ Morsel Objects
    in HTTP requests, and is not accessible through JavaScript. This is intended
    to mitigate some forms of cross-site scripting.
 
-   The attribute :attr:`samesite` specifies that the browser is not allowed to
-   send the cookie along with cross-site requests. This helps to mitigate CSRF
-   attacks. Valid values for this attribute are "Strict" and "Lax".
+   The attribute :attr:`samesite` controls when the browser sends the cookie with
+   cross-site requests. This helps to mitigate CSRF attacks. Valid values are
+   "Strict" (only sent with same-site requests), "Lax" (sent with same-site
+   requests and top-level navigations), and "None" (sent with same-site and
+   cross-site requests). When using "None", the "secure" attribute must also
+   be set, as required by modern browsers.
 
    The attribute :attr:`partitioned` indicates to user agents that these
    cross-site cookies *should* only be available in the same top-level context

Doc/library/multiprocessing.rst

@@ -97,6 +97,10 @@ To show the individual process IDs involved, here is an expanded example::
 For an explanation of why the ``if __name__ == '__main__'`` part is
 necessary, see :ref:`multiprocessing-programming`.
 
+The arguments to :class:`Process` usually need to be unpickleable from within
+the child process. If you tried typing the above example directly into a REPL it
+could lead to an :exc:`AttributeError` in the child process trying to locate the
+*f* function in the ``__main__`` module.
 
 
 .. _multiprocessing-start-methods:
@@ -233,9 +237,12 @@ processes for a different context.  In particular, locks created using
 the *fork* context cannot be passed to processes started using the
 *spawn* or *forkserver* start methods.
 
-A library which wants to use a particular start method should probably
-use :func:`get_context` to avoid interfering with the choice of the
-library user.
+Libraries using :mod:`multiprocessing` or
+:class:`~concurrent.futures.ProcessPoolExecutor` should be designed to allow
+their users to provide their own multiprocessing context.  Using a specific
+context of your own within a library can lead to incompatibilities with the
+rest of the library user's application.  Always document if your library
+requires a specific start method.
 
 .. warning::
 
@@ -538,9 +545,42 @@ The :mod:`multiprocessing` package mostly replicates the API of the
    to pass to *target*.
 
    If a subclass overrides the constructor, it must make sure it invokes the
-   base class constructor (:meth:`Process.__init__`) before doing anything else
+   base class constructor (``super().__init__()``) before doing anything else
    to the process.
 
+   .. note::
+
+      In general, all arguments to :class:`Process` must be picklable.  This is
+      frequently observed when trying to create a :class:`Process` or use a
+      :class:`concurrent.futures.ProcessPoolExecutor` from a REPL with a
+      locally defined *target* function.
+
+      Passing a callable object defined in the current REPL session causes the
+      child process to die via an uncaught :exc:`AttributeError` exception when
+      starting as *target* must have been defined within an importable module
+      in order to be loaded during unpickling.
+
+      Example of this uncatchable error from the child::
+
+         >>> import multiprocessing as mp
+         >>> def knigit():
+         ...     print("Ni!")
+         ...
+         >>> process = mp.Process(target=knigit)
+         >>> process.start()
+         >>> Traceback (most recent call last):
+           File ".../multiprocessing/spawn.py", line ..., in spawn_main
+           File ".../multiprocessing/spawn.py", line ..., in _main
+         AttributeError: module '__main__' has no attribute 'knigit'
+         >>> process
+         <SpawnProcess name='SpawnProcess-1' pid=379473 parent=378707 stopped exitcode=1>
+
+      See :ref:`multiprocessing-programming-spawn`.  While this restriction is
+      not true if using the ``"fork"`` start method, as of Python ``3.14`` that
+      is no longer the default on any platform.  See
+      :ref:`multiprocessing-start-methods`.
+      See also :gh:`132898`.
+
    .. versionchanged:: 3.3
       Added the *daemon* parameter.
 
@@ -3070,10 +3110,10 @@ start method.
 
 More picklability
 
-    Ensure that all arguments to :meth:`Process.__init__` are picklable.
-    Also, if you subclass :class:`~multiprocessing.Process` then make sure that
-    instances will be picklable when the :meth:`Process.start
-    <multiprocessing.Process.start>` method is called.
+    Ensure that all arguments to :class:`~multiprocessing.Process` are
+    picklable.  Also, if you subclass ``Process.__init__``, you must make sure
+    that instances will be picklable when the
+    :meth:`Process.start <multiprocessing.Process.start>` method is called.
 
 Global variables
 

Doc/library/queue.rst

@@ -187,9 +187,6 @@ fully processed by daemon consumer threads.
    processed (meaning that a :meth:`task_done` call was received for every item
    that had been :meth:`put` into the queue).
 
-   ``shutdown(immediate=True)`` calls :meth:`task_done` for each remaining item
-   in the queue.
-
    Raises a :exc:`ValueError` if called more times than there were items placed in
    the queue.
 
@@ -204,6 +201,9 @@ fully processed by daemon consumer threads.
    count of unfinished tasks drops to zero, :meth:`join` unblocks.
 
 
+Waiting for task completion
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
 Example of how to wait for enqueued tasks to be completed::
 
     import threading
@@ -233,22 +233,39 @@ Example of how to wait for enqueued tasks to be completed::
 Terminating queues
 ^^^^^^^^^^^^^^^^^^
 
-:class:`Queue` objects can be made to prevent further interaction by shutting
-them down.
+When no longer needed, :class:`Queue` objects can be wound down
+until empty or terminated immediately with a hard shutdown.
 
 .. method:: Queue.shutdown(immediate=False)
 
-   Shut down the queue, making :meth:`~Queue.get` and :meth:`~Queue.put` raise
-   :exc:`ShutDown`.
+   Put a :class:`Queue` instance into a shutdown mode.
+
+   The queue can no longer grow.
+   Future calls to :meth:`~Queue.put` raise :exc:`ShutDown`.
+   Currently blocked callers of :meth:`~Queue.put` will be unblocked
+   and will raise :exc:`ShutDown` in the formerly blocked thread.
+
+   If *immediate* is false (the default), the queue can be wound
+   down normally with :meth:`~Queue.get` calls to extract tasks
+   that have already been loaded.
+
+   And if :meth:`~Queue.task_done` is called for each remaining task, a
+   pending :meth:`~Queue.join` will be unblocked normally.
+
+   Once the queue is empty, future calls to :meth:`~Queue.get` will
+   raise :exc:`ShutDown`.
 
-   By default, :meth:`~Queue.get` on a shut down queue will only raise once the
-   queue is empty. Set *immediate* to true to make :meth:`~Queue.get` raise
-   immediately instead.
+   If *immediate* is true, the queue is terminated immediately.
+   The queue is drained to be completely empty and the count
+   of unfinished tasks is reduced by the number of tasks drained.
+   If unfinished tasks is zero, callers of :meth:`~Queue.join`
+   are unblocked.  Also, blocked callers of :meth:`~Queue.get`
+   are unblocked and will raise :exc:`ShutDown` because the
+   queue is empty.
 
-   All blocked callers of :meth:`~Queue.put` and :meth:`~Queue.get` will be
-   unblocked. If *immediate* is true, a task will be marked as done for each
-   remaining item in the queue, which may unblock callers of
-   :meth:`~Queue.join`.
+   Use caution when using :meth:`~Queue.join` with *immediate* set
+   to true. This unblocks the join even when no work has been done
+   on the tasks, violating the usual invariant for joining a queue.
 
    .. versionadded:: 3.13