diff options
Diffstat (limited to 'Doc/library')
| -rw-r--r-- | Doc/library/codecs.rst | 8 | ||||
| -rw-r--r-- | Doc/library/compression.zstd.rst | 10 | ||||
| -rw-r--r-- | Doc/library/concurrent.interpreters.rst | 223 | ||||
| -rw-r--r-- | Doc/library/csv.rst | 42 | ||||
| -rw-r--r-- | Doc/library/exceptions.rst | 9 | ||||
| -rw-r--r-- | Doc/library/fractions.rst | 2 | ||||
| -rw-r--r-- | Doc/library/math.rst | 2 | ||||
| -rw-r--r-- | Doc/library/shutil.rst | 11 | ||||
| -rw-r--r-- | Doc/library/sys.monitoring.rst | 61 | ||||
| -rw-r--r-- | Doc/library/tarfile.rst | 31 | ||||
| -rw-r--r-- | Doc/library/time.rst | 7 | ||||
| -rw-r--r-- | Doc/library/unittest.rst | 9 | ||||
| -rw-r--r-- | Doc/library/venv.rst | 70 | ||||
| -rw-r--r-- | Doc/library/zipfile.rst | 44 |
14 files changed, 422 insertions, 107 deletions
diff --git a/Doc/library/codecs.rst b/Doc/library/codecs.rst index 86511602fa5..b231fa568cf 100644 --- a/Doc/library/codecs.rst +++ b/Doc/library/codecs.rst @@ -53,6 +53,14 @@ any codec: :exc:`UnicodeDecodeError`). Refer to :ref:`codec-base-classes` for more information on codec error handling. +.. function:: charmap_build(string) + + Return a mapping suitable for encoding with a custom single-byte encoding. + Given a :class:`str` *string* of up to 256 characters representing a + decoding table, returns either a compact internal mapping object + ``EncodingMap`` or a :class:`dictionary <dict>` mapping character ordinals + to byte values. Raises a :exc:`TypeError` on invalid input. + The full details for each codec can also be looked up directly: .. function:: lookup(encoding, /) diff --git a/Doc/library/compression.zstd.rst b/Doc/library/compression.zstd.rst index 57ad8e3377f..a901403621b 100644 --- a/Doc/library/compression.zstd.rst +++ b/Doc/library/compression.zstd.rst @@ -523,8 +523,14 @@ Advanced parameter control .. attribute:: compression_level A high-level means of setting other compression parameters that affect - the speed and ratio of compressing data. Setting the level to zero uses - :attr:`COMPRESSION_LEVEL_DEFAULT`. + the speed and ratio of compressing data. + + Regular compression levels are greater than ``0``. Values greater than + ``20`` are considered "ultra" compression and require more memory than + other levels. Negative values can be used to trade off faster compression + for worse compression ratios. + + Setting the level to zero uses :attr:`COMPRESSION_LEVEL_DEFAULT`. .. attribute:: window_log diff --git a/Doc/library/concurrent.interpreters.rst b/Doc/library/concurrent.interpreters.rst index 8860418e87a..524d505bcf1 100644 --- a/Doc/library/concurrent.interpreters.rst +++ b/Doc/library/concurrent.interpreters.rst @@ -13,17 +13,26 @@ -------------- - -Introduction ------------- - The :mod:`!concurrent.interpreters` module constructs higher-level interfaces on top of the lower level :mod:`!_interpreters` module. -.. XXX Add references to the upcoming HOWTO docs in the seealso block. +The module is primarily meant to provide a basic API for managing +interpreters (AKA "subinterpreters") and running things in them. +Running mostly involves switching to an interpreter (in the current +thread) and calling a function in that execution context. + +For concurrency, interpreters themselves (and this module) don't +provide much more than isolation, which on its own isn't useful. +Actual concurrency is available separately through +:mod:`threads <threading>` See `below <interp-concurrency_>`_ .. seealso:: + :class:`~concurrent.futures.InterpreterPoolExecutor` + combines threads with interpreters in a familiar interface. + + .. XXX Add references to the upcoming HOWTO docs in the seealso block. + :ref:`isolating-extensions-howto` how to update an extension module to support multiple interpreters @@ -41,18 +50,155 @@ interfaces on top of the lower level :mod:`!_interpreters` module. Key details ----------- -Before we dive into examples, there are a small number of details +Before we dive in further, there are a small number of details to keep in mind about using multiple interpreters: -* isolated, by default +* `isolated <interp-isolation_>`_, by default * no implicit threads * not all PyPI packages support use in multiple interpreters yet .. XXX Are there other relevant details to list? -In the context of multiple interpreters, "isolated" means that -different interpreters do not share any state. In practice, there is some -process-global data they all share, but that is managed by the runtime. + +.. _interpreters-intro: + +Introduction +------------ + +An "interpreter" is effectively the execution context of the Python +runtime. It contains all of the state the runtime needs to execute +a program. This includes things like the import state and builtins. +(Each thread, even if there's only the main thread, has some extra +runtime state, in addition to the current interpreter, related to +the current exception and the bytecode eval loop.) + +The concept and functionality of the interpreter have been a part of +Python since version 2.2, but the feature was only available through +the C-API and not well known, and the `isolation <interp-isolation_>`_ +was relatively incomplete until version 3.12. + +.. _interp-isolation: + +Multiple Interpreters and Isolation +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +A Python implementation may support using multiple interpreters in the +same process. CPython has this support. Each interpreter is +effectively isolated from the others (with a limited number of +carefully managed process-global exceptions to the rule). + +That isolation is primarily useful as a strong separation between +distinct logical components of a program, where you want to have +careful control of how those components interact. + +.. note:: + + Interpreters in the same process can technically never be strictly + isolated from one another since there are few restrictions on memory + access within the same process. The Python runtime makes a best + effort at isolation but extension modules may easily violate that. + Therefore, do not use multiple interpreters in security-sensitive + situations, where they shouldn't have access to each other's data. + +Running in an Interpreter +^^^^^^^^^^^^^^^^^^^^^^^^^ + +Running in a different interpreter involves switching to it in the +current thread and then calling some function. The runtime will +execute the function using the current interpreter's state. The +:mod:`!concurrent.interpreters` module provides a basic API for +creating and managing interpreters, as well as the switch-and-call +operation. + +No other threads are automatically started for the operation. +There is `a helper <interp-call-in-thread_>`_ for that though. +There is another dedicated helper for calling the builtin +:func:`exec` in an interpreter. + +When :func:`exec` (or :func:`eval`) are called in an interpreter, +they run using the interpreter's :mod:`!__main__` module as the +"globals" namespace. The same is true for functions that aren't +associated with any module. This is the same as how scripts invoked +from the command-line run in the :mod:`!__main__` module. + + +.. _interp-concurrency: + +Concurrency and Parallelism +^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +As noted earlier, interpreters do not provide any concurrency +on their own. They strictly represent the isolated execution +context the runtime will use *in the current thread*. That isolation +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. +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, +a model which is relatively easy to reason about. + +You can take advantage of that concurrency model in a single thread, +switching back and forth between interpreters, Stackless-style. +However, this model is more useful when you combine interpreters +with multiple threads. This mostly involves starting a new thread, +where you switch to another interpreter and run what you want there. + +Each actual thread in Python, even if you're only running in the main +thread, has its own *current* execution context. Multiple threads can +use the same interpreter or different ones. + +At a high level, you can think of the combination of threads and +interpreters as threads with opt-in sharing. + +As a significant bonus, interpreters are sufficiently isolated that +they do not share the :term:`GIL`, which means combining threads with +multiple interpreters enables full multi-core parallelism. +(This has been the case since Python 3.12.) + +Communication Between Interpreters +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +In practice, multiple interpreters are useful only if we have a way +to communicate between them. This usually involves some form of +message passing, but can even mean sharing data in some carefully +managed way. + +With this in mind, the :mod:`!concurrent.interpreters` module provides +a :class:`queue.Queue` implementation, available through +:func:`create_queue`. + +.. _interp-object-sharing: + +"Sharing" Objects +^^^^^^^^^^^^^^^^^ + +Any data actually shared between interpreters loses the thread-safety +provided by the :term:`GIL`. There are various options for dealing with +this in extension modules. However, from Python code the lack of +thread-safety means objects can't actually be shared, with a few +exceptions. Instead, a copy must be created, which means mutable +objects won't stay in sync. + +By default, most objects are copied with :mod:`pickle` when they are +passed to another interpreter. Nearly all of the immutable builtin +objects are either directly shared or copied efficiently. For example: + +* :const:`None` +* :class:`bool` (:const:`True` and :const:`False`) +* :class:`bytes` +* :class:`str` +* :class:`int` +* :class:`float` +* :class:`tuple` (of similarly supported objects) + +There is a small number of Python types that actually share mutable +data between interpreters: + +* :class:`memoryview` +* :class:`Queue` Reference @@ -73,12 +219,19 @@ This module defines the following functions: .. function:: get_main() Return an :class:`Interpreter` object for the main interpreter. + This is the interpreter the runtime created to run the :term:`REPL` + or the script given at the command-line. It is usually the only one. .. function:: create() Initialize a new (idle) Python interpreter and return a :class:`Interpreter` object for it. +.. function:: create_queue() + + Initialize a new cross-interpreter queue and return a :class:`Queue` + object for it. + Interpreter objects ^^^^^^^^^^^^^^^^^^^ @@ -94,7 +247,7 @@ Interpreter objects (read-only) - The interpreter's ID. + The underlying interpreter's ID. .. attribute:: whence @@ -113,8 +266,10 @@ Interpreter objects .. method:: prepare_main(ns=None, **kwargs) - Bind "shareable" objects in the interpreter's - :mod:`!__main__` module. + Bind objects in the interpreter's :mod:`!__main__` module. + + Some objects are actually shared and some are copied efficiently, + but most are copied via :mod:`pickle`. See :ref:`interp-object-sharing`. .. method:: exec(code, /, dedent=True) @@ -125,6 +280,8 @@ Interpreter objects Return the result of calling running the given function in the interpreter (in the current thread). + .. _interp-call-in-thread: + .. method:: call_in_thread(callable, /, *args, **kwargs) Run the given function in the interpreter (in a new thread). @@ -159,7 +316,36 @@ Exceptions an object cannot be sent to another interpreter. -.. XXX Add functions for communicating between interpreters. +Communicating Between Interpreters +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. class:: Queue(id) + + A wrapper around a low-level, cross-interpreter queue, which + implements the :class:`queue.Queue` interface. The underlying queue + can only be created through :func:`create_queue`. + + Some objects are actually shared and some are copied efficiently, + but most are copied via :mod:`pickle`. See :ref:`interp-object-sharing`. + + .. attribute:: id + + (read-only) + + The queue's ID. + + +.. exception:: QueueEmptyError + + This exception, a subclass of :exc:`queue.Empty`, is raised from + :meth:`!Queue.get` and :meth:`!Queue.get_nowait` when the queue + is empty. + +.. exception:: QueueFullError + + This exception, a subclass of :exc:`queue.Full`, is raised from + :meth:`!Queue.put` and :meth:`!Queue.put_nowait` when the queue + is full. Basic usage @@ -184,6 +370,12 @@ Creating an interpreter and running code in it:: print('spam!') """)) + def run(arg): + return arg + + res = interp.call(run, 'spam!') + print(res) + def run(): print('spam!') @@ -193,6 +385,3 @@ Creating an interpreter and running code in it:: t = interp.call_in_thread(run) t.join() - - -.. XXX Explain about object "sharing". diff --git a/Doc/library/csv.rst b/Doc/library/csv.rst index 2e513bff651..d39c4ca4a58 100644 --- a/Doc/library/csv.rst +++ b/Doc/library/csv.rst @@ -53,7 +53,7 @@ The :mod:`csv` module defines the following functions: .. index:: single: universal newlines; csv.reader function -.. function:: reader(csvfile, dialect='excel', **fmtparams) +.. function:: reader(csvfile, /, dialect='excel', **fmtparams) Return a :ref:`reader object <reader-objects>` that will process lines from the given *csvfile*. A csvfile must be an iterable of @@ -84,7 +84,7 @@ The :mod:`csv` module defines the following functions: Spam, Lovely Spam, Wonderful Spam -.. function:: writer(csvfile, dialect='excel', **fmtparams) +.. function:: writer(csvfile, /, dialect='excel', **fmtparams) Return a writer object responsible for converting the user's data into delimited strings on the given file-like object. *csvfile* can be any object with a @@ -323,8 +323,8 @@ The :mod:`csv` module defines the following constants: .. data:: QUOTE_MINIMAL Instructs :class:`writer` objects to only quote those fields which contain - special characters such as *delimiter*, *quotechar* or any of the characters in - *lineterminator*. + special characters such as *delimiter*, *quotechar*, ``'\r'``, ``'\n'`` + or any of the characters in *lineterminator*. .. data:: QUOTE_NONNUMERIC @@ -342,10 +342,13 @@ The :mod:`csv` module defines the following constants: .. data:: QUOTE_NONE - Instructs :class:`writer` objects to never quote fields. When the current - *delimiter* occurs in output data it is preceded by the current *escapechar* - character. If *escapechar* is not set, the writer will raise :exc:`Error` if + Instructs :class:`writer` objects to never quote fields. + When the current *delimiter*, *quotechar*, *escapechar*, ``'\r'``, ``'\n'`` + or any of the characters in *lineterminator* occurs in output data + it is preceded by the current *escapechar* character. + If *escapechar* is not set, the writer will raise :exc:`Error` if any characters that require escaping are encountered. + Set *quotechar* to ``None`` to prevent its escaping. Instructs :class:`reader` objects to perform no special processing of quote characters. @@ -414,9 +417,16 @@ Dialects support the following attributes: .. attribute:: Dialect.escapechar - A one-character string used by the writer to escape the *delimiter* if *quoting* - is set to :const:`QUOTE_NONE` and the *quotechar* if *doublequote* is - :const:`False`. On reading, the *escapechar* removes any special meaning from + A one-character string used by the writer to escape characters that + require escaping: + + * the *delimiter*, the *quotechar*, ``'\r'``, ``'\n'`` and any of the + characters in *lineterminator* are escaped if *quoting* is set to + :const:`QUOTE_NONE`; + * the *quotechar* is escaped if *doublequote* is :const:`False`; + * the *escapechar* itself. + + On reading, the *escapechar* removes any special meaning from the following character. It defaults to :const:`None`, which disables escaping. .. versionchanged:: 3.11 @@ -436,9 +446,12 @@ Dialects support the following attributes: .. attribute:: Dialect.quotechar - A one-character string used to quote fields containing special characters, such - as the *delimiter* or *quotechar*, or which contain new-line characters. It - defaults to ``'"'``. + A one-character string used to quote fields containing special characters, + such as the *delimiter* or the *quotechar*, or which contain new-line + characters (``'\r'``, ``'\n'`` or any of the characters in *lineterminator*). + It defaults to ``'"'``. + Can be set to ``None`` to prevent escaping ``'"'`` if *quoting* is set + to :const:`QUOTE_NONE`. .. versionchanged:: 3.11 An empty *quotechar* is not allowed. @@ -447,7 +460,8 @@ Dialects support the following attributes: Controls when quotes should be generated by the writer and recognised by the reader. It can take on any of the :ref:`QUOTE_\* constants <csv-constants>` - and defaults to :const:`QUOTE_MINIMAL`. + and defaults to :const:`QUOTE_MINIMAL` if *quotechar* is not ``None``, + and :const:`QUOTE_NONE` otherwise. .. attribute:: Dialect.skipinitialspace diff --git a/Doc/library/exceptions.rst b/Doc/library/exceptions.rst index 9806ae80905..c09e1615a5b 100644 --- a/Doc/library/exceptions.rst +++ b/Doc/library/exceptions.rst @@ -429,7 +429,9 @@ The following exceptions are the exceptions that are usually raised. * Creating a new Python thread. * :meth:`Joining <threading.Thread.join>` a running daemon thread. - * :func:`os.fork`. + * :func:`os.fork`, + * acquiring a lock such as :class:`threading.Lock`, when it is known that + the operation would otherwise deadlock. See also the :func:`sys.is_finalizing` function. @@ -440,6 +442,11 @@ The following exceptions are the exceptions that are usually raised. :meth:`threading.Thread.join` can now raise this exception. + .. versionchanged:: next + + This exception may be raised when acquiring :meth:`threading.Lock` + or :meth:`threading.RLock`. + .. exception:: RecursionError This exception is derived from :exc:`RuntimeError`. It is raised when the diff --git a/Doc/library/fractions.rst b/Doc/library/fractions.rst index fc7f9a6301a..392b6d40e86 100644 --- a/Doc/library/fractions.rst +++ b/Doc/library/fractions.rst @@ -142,7 +142,7 @@ another rational number, or from a string. .. versionadded:: 3.12 - .. classmethod:: from_float(flt) + .. classmethod:: from_float(f) Alternative constructor which only accepts instances of :class:`float` or :class:`numbers.Integral`. Beware that diff --git a/Doc/library/math.rst b/Doc/library/math.rst index 03da0e4713c..bf7a00549fc 100644 --- a/Doc/library/math.rst +++ b/Doc/library/math.rst @@ -804,7 +804,7 @@ Constants The mathematical constant *τ* = 6.283185..., to available precision. Tau is a circle constant equal to 2\ *π*, the ratio of a circle's circumference to its radius. To learn more about Tau, check out Vi Hart's video `Pi is (still) - Wrong <https://www.youtube.com/watch?v=jG7vhMMXagQ>`_, and start celebrating + Wrong <https://vimeo.com/147792667>`_, and start celebrating `Tau day <https://tauday.com/>`_ by eating twice as much pie! .. versionadded:: 3.6 diff --git a/Doc/library/shutil.rst b/Doc/library/shutil.rst index 2dde40c9d92..dde38498206 100644 --- a/Doc/library/shutil.rst +++ b/Doc/library/shutil.rst @@ -618,7 +618,8 @@ provided. They rely on the :mod:`zipfile` and :mod:`tarfile` modules. *format* is the archive format: one of "zip" (if the :mod:`zlib` module is available), "tar", "gztar" (if the :mod:`zlib` module is available), "bztar" (if the :mod:`bz2` module is - available), or "xztar" (if the :mod:`lzma` module is available). + available), "xztar" (if the :mod:`lzma` module is available), or "zstdtar" + (if the :mod:`compression.zstd` module is available). *root_dir* is a directory that will be the root directory of the archive, all paths in the archive will be relative to it; for example, @@ -673,6 +674,8 @@ provided. They rely on the :mod:`zipfile` and :mod:`tarfile` modules. - *gztar*: gzip'ed tar-file (if the :mod:`zlib` module is available). - *bztar*: bzip2'ed tar-file (if the :mod:`bz2` module is available). - *xztar*: xz'ed tar-file (if the :mod:`lzma` module is available). + - *zstdtar*: Zstandard compressed tar-file (if the :mod:`compression.zstd` + module is available). You can register new formats or provide your own archiver for any existing formats, by using :func:`register_archive_format`. @@ -716,8 +719,8 @@ provided. They rely on the :mod:`zipfile` and :mod:`tarfile` modules. *extract_dir* is the name of the target directory where the archive is unpacked. If not provided, the current working directory is used. - *format* is the archive format: one of "zip", "tar", "gztar", "bztar", or - "xztar". Or any other format registered with + *format* is the archive format: one of "zip", "tar", "gztar", "bztar", + "xztar", or "zstdtar". Or any other format registered with :func:`register_unpack_format`. If not provided, :func:`unpack_archive` will use the archive file name extension and see if an unpacker was registered for that extension. In case none is found, @@ -789,6 +792,8 @@ provided. They rely on the :mod:`zipfile` and :mod:`tarfile` modules. - *gztar*: gzip'ed tar-file (if the :mod:`zlib` module is available). - *bztar*: bzip2'ed tar-file (if the :mod:`bz2` module is available). - *xztar*: xz'ed tar-file (if the :mod:`lzma` module is available). + - *zstdtar*: Zstandard compressed tar-file (if the :mod:`compression.zstd` + module is available). You can register new formats or provide your own unpacker for any existing formats, by using :func:`register_unpack_format`. diff --git a/Doc/library/sys.monitoring.rst b/Doc/library/sys.monitoring.rst index 0674074b8c0..f62a4011e41 100644 --- a/Doc/library/sys.monitoring.rst +++ b/Doc/library/sys.monitoring.rst @@ -137,7 +137,8 @@ The following events are supported: .. monitoring-event:: PY_UNWIND - Exit from a Python function during exception unwinding. + Exit from a Python function during exception unwinding. This includes exceptions raised directly within the + function and that are allowed to continue to propagate. .. monitoring-event:: PY_YIELD @@ -171,7 +172,7 @@ events, use the expression ``PY_RETURN | PY_START``. if get_events(DEBUGGER_ID) == NO_EVENTS: ... -Events are divided into three groups: + Setting this event deactivates all events. .. _monitoring-event-local: @@ -243,20 +244,23 @@ raise an exception unless it would be visible to other code. To allow tools to monitor for real exceptions without slowing down generators and coroutines, the :monitoring-event:`STOP_ITERATION` event is provided. -:monitoring-event:`STOP_ITERATION` can be locally disabled, unlike :monitoring-event:`RAISE`. +:monitoring-event:`STOP_ITERATION` can be locally disabled, unlike +:monitoring-event:`RAISE`. -Note that the :monitoring-event:`STOP_ITERATION` event and the :monitoring-event:`RAISE` -event for a :exc:`StopIteration` exception are equivalent, and are treated as interchangeable -when generating events. Implementations will favor :monitoring-event:`STOP_ITERATION` for -performance reasons, but may generate a :monitoring-event:`RAISE` event with a :exc:`StopIteration`. +Note that the :monitoring-event:`STOP_ITERATION` event and the +:monitoring-event:`RAISE` event for a :exc:`StopIteration` exception are +equivalent, and are treated as interchangeable when generating events. +Implementations will favor :monitoring-event:`STOP_ITERATION` for performance +reasons, but may generate a :monitoring-event:`RAISE` event with a +:exc:`StopIteration`. Turning events on and off ------------------------- In order to monitor an event, it must be turned on and a corresponding callback -must be registered. -Events can be turned on or off by setting the events either globally or -for a particular code object. +must be registered. Events can be turned on or off by setting the events either +globally and/or for a particular code object. An event will trigger only once, +even if it is turned on both globally and locally. Setting events globally @@ -292,10 +296,6 @@ in Python (see :ref:`c-api-monitoring`). Activates all the local events for *code* which are set in *event_set*. Raises a :exc:`ValueError` if *tool_id* is not in use. -Local events add to global events, but do not mask them. -In other words, all global events will trigger for a code object, -regardless of the local events. - Disabling events '''''''''''''''' @@ -325,8 +325,6 @@ except for a few breakpoints. Registering callback functions ------------------------------ -To register a callable for events call - .. function:: register_callback(tool_id: int, event: int, func: Callable | None, /) -> Callable | None Registers the callable *func* for the *event* with the given *tool_id* @@ -335,12 +333,16 @@ To register a callable for events call it is unregistered and returned. Otherwise :func:`register_callback` returns ``None``. - Functions can be unregistered by calling ``sys.monitoring.register_callback(tool_id, event, None)``. Callback functions can be registered and unregistered at any time. +Callbacks are called only once regardless if the event is turned on both +globally and locally. As such, if an event could be turned on for both global +and local events by your code then the callback needs to be written to handle +either trigger. + Registering or unregistering a callback function will generate a :func:`sys.audit` event. @@ -353,37 +355,46 @@ Callback function arguments that there are no arguments to the call. When an active event occurs, the registered callback function is called. +Callback functions returning an object other than :data:`DISABLE` will have no effect. Different events will provide the callback function with different arguments, as follows: * :monitoring-event:`PY_START` and :monitoring-event:`PY_RESUME`:: - func(code: CodeType, instruction_offset: int) -> DISABLE | Any + func(code: CodeType, instruction_offset: int) -> object * :monitoring-event:`PY_RETURN` and :monitoring-event:`PY_YIELD`:: - func(code: CodeType, instruction_offset: int, retval: object) -> DISABLE | Any + func(code: CodeType, instruction_offset: int, retval: object) -> object -* :monitoring-event:`CALL`, :monitoring-event:`C_RAISE` and :monitoring-event:`C_RETURN`:: +* :monitoring-event:`CALL`, :monitoring-event:`C_RAISE` and :monitoring-event:`C_RETURN` + (*arg0* can be :data:`MISSING` specifically):: - func(code: CodeType, instruction_offset: int, callable: object, arg0: object | MISSING) -> DISABLE | Any + func(code: CodeType, instruction_offset: int, callable: object, arg0: object) -> object + *code* represents the code object where the call is being made, while + *callable* is the object that is about to be called (and thus + triggered the event). If there are no arguments, *arg0* is set to :data:`sys.monitoring.MISSING`. + For instance methods, *callable* will be the function object as found on the + class with *arg0* set to the instance (i.e. the ``self`` argument to the + method). + * :monitoring-event:`RAISE`, :monitoring-event:`RERAISE`, :monitoring-event:`EXCEPTION_HANDLED`, :monitoring-event:`PY_UNWIND`, :monitoring-event:`PY_THROW` and :monitoring-event:`STOP_ITERATION`:: - func(code: CodeType, instruction_offset: int, exception: BaseException) -> DISABLE | Any + func(code: CodeType, instruction_offset: int, exception: BaseException) -> object * :monitoring-event:`LINE`:: - func(code: CodeType, line_number: int) -> DISABLE | Any + func(code: CodeType, line_number: int) -> object * :monitoring-event:`BRANCH_LEFT`, :monitoring-event:`BRANCH_RIGHT` and :monitoring-event:`JUMP`:: - func(code: CodeType, instruction_offset: int, destination_offset: int) -> DISABLE | Any + func(code: CodeType, instruction_offset: int, destination_offset: int) -> object Note that the *destination_offset* is where the code will next execute. * :monitoring-event:`INSTRUCTION`:: - func(code: CodeType, instruction_offset: int) -> DISABLE | Any + func(code: CodeType, instruction_offset: int) -> object diff --git a/Doc/library/tarfile.rst b/Doc/library/tarfile.rst index 7cec108a5bd..70466fbbc4d 100644 --- a/Doc/library/tarfile.rst +++ b/Doc/library/tarfile.rst @@ -18,8 +18,8 @@ higher-level functions in :ref:`shutil <archiving-operations>`. Some facts and figures: -* reads and writes :mod:`gzip`, :mod:`bz2` and :mod:`lzma` compressed archives - if the respective modules are available. +* reads and writes :mod:`gzip`, :mod:`bz2`, :mod:`compression.zstd`, and + :mod:`lzma` compressed archives if the respective modules are available. * read/write support for the POSIX.1-1988 (ustar) format. @@ -47,6 +47,10 @@ Some facts and figures: or paths outside of the destination. Previously, the filter strategy was equivalent to :func:`fully_trusted <fully_trusted_filter>`. +.. versionchanged:: 3.14 + + Added support for Zstandard compression using :mod:`compression.zstd`. + .. function:: open(name=None, mode='r', fileobj=None, bufsize=10240, **kwargs) Return a :class:`TarFile` object for the pathname *name*. For detailed @@ -71,6 +75,8 @@ Some facts and figures: +------------------+---------------------------------------------+ | ``'r:xz'`` | Open for reading with lzma compression. | +------------------+---------------------------------------------+ + | ``'r:zst'`` | Open for reading with Zstandard compression.| + +------------------+---------------------------------------------+ | ``'x'`` or | Create a tarfile exclusively without | | ``'x:'`` | compression. | | | Raise a :exc:`FileExistsError` exception | @@ -88,6 +94,10 @@ Some facts and figures: | | Raise a :exc:`FileExistsError` exception | | | if it already exists. | +------------------+---------------------------------------------+ + | ``'x:zst'`` | Create a tarfile with Zstandard compression.| + | | Raise a :exc:`FileExistsError` exception | + | | if it already exists. | + +------------------+---------------------------------------------+ | ``'a' or 'a:'`` | Open for appending with no compression. The | | | file is created if it does not exist. | +------------------+---------------------------------------------+ @@ -99,6 +109,8 @@ Some facts and figures: +------------------+---------------------------------------------+ | ``'w:xz'`` | Open for lzma compressed writing. | +------------------+---------------------------------------------+ + | ``'w:zst'`` | Open for Zstandard compressed writing. | + +------------------+---------------------------------------------+ Note that ``'a:gz'``, ``'a:bz2'`` or ``'a:xz'`` is not possible. If *mode* is not suitable to open a certain (compressed) file for reading, @@ -115,6 +127,15 @@ Some facts and figures: For modes ``'w:xz'``, ``'x:xz'`` and ``'w|xz'``, :func:`tarfile.open` accepts the keyword argument *preset* to specify the compression level of the file. + For modes ``'w:zst'``, ``'x:zst'`` and ``'w|zst'``, :func:`tarfile.open` + accepts the keyword argument *level* to specify the compression level of + the file. The keyword argument *options* may also be passed, providing + advanced Zstandard compression parameters described by + :class:`~compression.zstd.CompressionParameter`. The keyword argument + *zstd_dict* can be passed to provide a :class:`~compression.zstd.ZstdDict`, + a Zstandard dictionary used to improve compression of smaller amounts of + data. + For special purposes, there is a second format for *mode*: ``'filemode|[compression]'``. :func:`tarfile.open` will return a :class:`TarFile` object that processes its data as a stream of blocks. No random seeking will @@ -146,6 +167,9 @@ Some facts and figures: | ``'r|xz'`` | Open an lzma compressed *stream* for | | | reading. | +-------------+--------------------------------------------+ + | ``'r|zst'`` | Open a Zstandard compressed *stream* for | + | | reading. | + +-------------+--------------------------------------------+ | ``'w|'`` | Open an uncompressed *stream* for writing. | +-------------+--------------------------------------------+ | ``'w|gz'`` | Open a gzip compressed *stream* for | @@ -157,6 +181,9 @@ Some facts and figures: | ``'w|xz'`` | Open an lzma compressed *stream* for | | | writing. | +-------------+--------------------------------------------+ + | ``'w|zst'`` | Open a Zstandard compressed *stream* for | + | | writing. | + +-------------+--------------------------------------------+ .. versionchanged:: 3.5 The ``'x'`` (exclusive creation) mode was added. diff --git a/Doc/library/time.rst b/Doc/library/time.rst index 542493a82af..29b695a9b19 100644 --- a/Doc/library/time.rst +++ b/Doc/library/time.rst @@ -712,13 +712,18 @@ Functions Clock: - * On Windows, call ``GetSystemTimeAsFileTime()``. + * On Windows, call ``GetSystemTimePreciseAsFileTime()``. * Call ``clock_gettime(CLOCK_REALTIME)`` if available. * Otherwise, call ``gettimeofday()``. Use :func:`time_ns` to avoid the precision loss caused by the :class:`float` type. +.. versionchanged:: 3.13 + + On Windows, calls ``GetSystemTimePreciseAsFileTime()`` instead of + ``GetSystemTimeAsFileTime()``. + .. function:: time_ns() -> int diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst index dcdda1719bf..d526e835caa 100644 --- a/Doc/library/unittest.rst +++ b/Doc/library/unittest.rst @@ -1131,7 +1131,7 @@ Test cases .. versionchanged:: 3.3 Added the *msg* keyword argument when used as a context manager. - .. method:: assertLogs(logger=None, level=None) + .. method:: assertLogs(logger=None, level=None, formatter=None) A context manager to test that at least one message is logged on the *logger* or one of its children, with at least the given @@ -1146,6 +1146,10 @@ Test cases its string equivalent (for example either ``"ERROR"`` or :const:`logging.ERROR`). The default is :const:`logging.INFO`. + If given, *formatter* should be a :class:`logging.Formatter` object. + The default is a formatter with format string + ``"%(levelname)s:%(name)s:%(message)s"`` + The test passes if at least one message emitted inside the ``with`` block matches the *logger* and *level* conditions, otherwise it fails. @@ -1173,6 +1177,9 @@ Test cases .. versionadded:: 3.4 + .. versionchanged:: next + Now accepts a *formatter* to control how messages are formatted. + .. method:: assertNoLogs(logger=None, level=None) A context manager to test that no messages are logged on diff --git a/Doc/library/venv.rst b/Doc/library/venv.rst index bed799aedfd..f16e24eac08 100644 --- a/Doc/library/venv.rst +++ b/Doc/library/venv.rst @@ -105,36 +105,52 @@ The command, if run with ``-h``, will show the available options:: Creates virtual Python environments in one or more target directories. - positional arguments: - ENV_DIR A directory to create the environment in. - - options: - -h, --help show this help message and exit - --system-site-packages - Give the virtual environment access to the system - site-packages dir. - --symlinks Try to use symlinks rather than copies, when - symlinks are not the default for the platform. - --copies Try to use copies rather than symlinks, even when - symlinks are the default for the platform. - --clear Delete the contents of the environment directory - if it already exists, before environment creation. - --upgrade Upgrade the environment directory to use this - version of Python, assuming Python has been - upgraded in-place. - --without-pip Skips installing or upgrading pip in the virtual - environment (pip is bootstrapped by default) - --prompt PROMPT Provides an alternative prompt prefix for this - environment. - --upgrade-deps Upgrade core dependencies (pip) to the latest - version in PyPI - --without-scm-ignore-files - Skips adding SCM ignore files to the environment - directory (Git is supported by default). - Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory. +.. _venv-cli: +.. program:: venv + +.. option:: ENV_DIR + + A required argument specifying the directory to create the environment in. + +.. option:: --system-site-packages + + Give the virtual environment access to the system site-packages directory. + +.. option:: --symlinks + + Try to use symlinks rather than copies, when symlinks are not the default for the platform. + +.. option:: --copies + + Try to use copies rather than symlinks, even when symlinks are the default for the platform. + +.. option:: --clear + + Delete the contents of the environment directory if it already exists, before environment creation. + +.. option:: --upgrade + + Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. + +.. option:: --without-pip + + Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default). + +.. option:: --prompt <PROMPT> + + Provides an alternative prompt prefix for this environment. + +.. option:: --upgrade-deps + + Upgrade core dependencies (pip) to the latest version in PyPI. + +.. option:: --without-scm-ignore-files + + Skips adding SCM ignore files to the environment directory (Git is supported by default). + .. versionchanged:: 3.4 Installs pip by default, added the ``--without-pip`` and ``--copies`` diff --git a/Doc/library/zipfile.rst b/Doc/library/zipfile.rst index 6a4fa67332e..bf9136a2139 100644 --- a/Doc/library/zipfile.rst +++ b/Doc/library/zipfile.rst @@ -129,14 +129,28 @@ The module defines the following items: .. versionadded:: 3.3 +.. data:: ZIP_ZSTANDARD + + The numeric constant for Zstandard compression. This requires the + :mod:`compression.zstd` module. + .. note:: - The ZIP file format specification has included support for bzip2 compression - since 2001, and for LZMA compression since 2006. However, some tools - (including older Python releases) do not support these compression - methods, and may either refuse to process the ZIP file altogether, - or fail to extract individual files. + In APPNOTE 6.3.7, the method ID ``20`` was assigned to Zstandard + compression. This was changed in APPNOTE 6.3.8 to method ID ``93`` to + avoid conflicts, with method ID ``20`` being deprecated. For + compatibility, the :mod:`!zipfile` module reads both method IDs but will + only write data with method ID ``93``. + + .. versionadded:: 3.14 + +.. note:: + The ZIP file format specification has included support for bzip2 compression + since 2001, for LZMA compression since 2006, and Zstandard compression since + 2020. However, some tools (including older Python releases) do not support + these compression methods, and may either refuse to process the ZIP file + altogether, or fail to extract individual files. .. seealso:: @@ -176,10 +190,11 @@ ZipFile Objects *compression* is the ZIP compression method to use when writing the archive, and should be :const:`ZIP_STORED`, :const:`ZIP_DEFLATED`, - :const:`ZIP_BZIP2` or :const:`ZIP_LZMA`; unrecognized - values will cause :exc:`NotImplementedError` to be raised. If - :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2` or :const:`ZIP_LZMA` is specified - but the corresponding module (:mod:`zlib`, :mod:`bz2` or :mod:`lzma`) is not + :const:`ZIP_BZIP2`, :const:`ZIP_LZMA`, or :const:`ZIP_ZSTANDARD`; + unrecognized values will cause :exc:`NotImplementedError` to be raised. If + :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2`, :const:`ZIP_LZMA`, or + :const:`ZIP_ZSTANDARD` is specified but the corresponding module + (:mod:`zlib`, :mod:`bz2`, :mod:`lzma`, or :mod:`compression.zstd`) is not available, :exc:`RuntimeError` is raised. The default is :const:`ZIP_STORED`. If *allowZip64* is ``True`` (the default) zipfile will create ZIP files that @@ -194,6 +209,10 @@ ZipFile Objects (see :class:`zlib <zlib.compressobj>` for more information). When using :const:`ZIP_BZIP2` integers ``1`` through ``9`` are accepted (see :class:`bz2 <bz2.BZ2File>` for more information). + When using :const:`ZIP_ZSTANDARD` integers ``-131072`` through ``22`` are + commonly accepted (see + :attr:`CompressionParameter.compression_level <compression.zstd.CompressionParameter.compression_level>` + for more on retrieving valid values and their meaning). The *strict_timestamps* argument, when set to ``False``, allows to zip files older than 1980-01-01 at the cost of setting the @@ -415,9 +434,10 @@ ZipFile Objects read or append. *pwd* is the password used for encrypted files as a :class:`bytes` object and, if specified, overrides the default password set with :meth:`setpassword`. Calling :meth:`read` on a ZipFile that uses a compression method other than - :const:`ZIP_STORED`, :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2` or - :const:`ZIP_LZMA` will raise a :exc:`NotImplementedError`. An error will also - be raised if the corresponding compression module is not available. + :const:`ZIP_STORED`, :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2`, + :const:`ZIP_LZMA`, or :const:`ZIP_ZSTANDARD` will raise a + :exc:`NotImplementedError`. An error will also be raised if the + corresponding compression module is not available. .. versionchanged:: 3.6 Calling :meth:`read` on a closed ZipFile will raise a :exc:`ValueError`. |