diff options
| -rw-r--r-- | Doc/whatsnew/3.2.rst | 112 |
1 files changed, 86 insertions, 26 deletions
diff --git a/Doc/whatsnew/3.2.rst b/Doc/whatsnew/3.2.rst index 4ba871e..c0bf224 100644 --- a/Doc/whatsnew/3.2.rst +++ b/Doc/whatsnew/3.2.rst @@ -394,13 +394,13 @@ Some smaller changes made to the core Python language are: (Contributed by Marcin Wojdyr in issue:`1772833`). -* The :func:`hasattr` function used to catch and suppress any Exception. Now, - it only catches :exc:`AttributeError`. Under the hood, :func:`hasattr` works - by calling :func:`getattr` and throwing away the results. This is necessary - because dynamic attribute creation is possible using :meth:`__getattribute__` - or :meth:`__getattr__`. If :func:`hasattr` were to just scan instance and class - dictionaries it would miss the dynamic methods and make it difficult to - implement proxy objects. +* The :func:`hasattr` function works by calling :func:`getattr` and detecting + whether an exception is raised. This technique allows it to detect methods + created dynamically by :meth:`__getattr__` or :meth:`__getattribute__` which + would be absent from the class dictionary. Formerly, *hasattr* would catch + any exception, possibly masking genuine errors in those methods. Now, + *hasattr* has been tightened to only catch :exc:`AttributeError` and let + other exceptions pass through. (Discovered by Yury Selivanov and fixed by Benjamin Peterson; :issue:`9666`.) @@ -682,9 +682,10 @@ functools return ((self.lastname.lower(), self.firstname.lower()) < (other.lastname.lower(), other.firstname.lower())) - (Contributed by Raymond Hettinger.) + With the *total_ordering* decorator, the remaining comparison methods + are filled-in automatically. -.. XXX clarify what the example does + (Contributed by Raymond Hettinger.) * To aid in porting programs from Python 2, the :func:`~functools.cmp_to_key` function converts an old-style comparison function to @@ -787,12 +788,10 @@ datetime * Also, :class:`~datetime.timedelta` objects can now be multiplied by :class:`float` and divided by :class:`float` and :class:`int` objects. + And :class:`~datetime.timedelta` objects can now divide one another. -.. XXX Describe added support for dividing a timedelta by another timedelta. - See revision 80290 and issue #2706. - - (Contributed by Alexander Belopolsky in :issue:`1289118`, :issue:`5094` and - :issue:`6641`.) + (Contributed by Alexander Belopolsky in :issue:`1289118`, :issue:`5094`, + :issue:`6641`, and :issue:`2706`.) abc --- @@ -861,7 +860,7 @@ body of enclosed statements. (Contributed by Michael Foord in :issue:`9110`.) decimal and fractions ---------------------- +---------------------- Mark Dickinson crafted an elegant and efficient scheme for assuring that different numeric datatypes will have the same hash value whenever their actual @@ -902,6 +901,16 @@ contexts that correspond to the decimal interchange formats specified in IEEE (Contributed by Mark Dickinson and Raymond Hettinger.) +codecs +------ + +In an effort to keep codec aliases solely focused on bytes-to-text encodings, +the *base64*, *bz2*, *hex*, *quopri*, *rot13*, *uu* and *zlib* codecs have been +removed from the codec aliases. These bytes-to-bytes conversion are still +accessible via codecs.lookup(). + +(see :issue:`10807`.) + ftp --- @@ -930,7 +939,11 @@ also grew auto-closing context managers:: (Contributed by Tarek Ziadé and Giampaolo Rodolà in :issue:`4972`, and by Georg Brandl in :issue:`8046` and :issue:`1286`.) -.. XXX mention os.popen and subprocess.Popen auto-closing of fds +popen +----- + +The :func:`os.popen` and :func:`subprocess.Popen` functions now support +the :keyword:`with`-statement` for auto-closing of the file descriptors. gzip and zipfile ---------------- @@ -1077,6 +1090,11 @@ as recommended in public uses of HTTPS. unittest -------- +The unittest module has a number of improvements supporting test discovery for +packages, easier experimentation at the interactive prompt, new testcase +methods, improved diagnostic messages for test failures, and better method +names. + * The command-line call, ``python -m unittest`` can now accept file paths instead of module names for running specific tests (:issue:`10620`). The new test discovery can find tests within packages, locating any test importable @@ -1088,14 +1106,24 @@ unittest (Contributed by Michael Foord.) +* Experimentation at the interactive prompt is now easier because the + :class:`unittest.case.TestCase` class can now be instantiated without + arguments: + + >>> TestCase().assertEqual(pow(2, 3), 8) + + (Contributed by Michael Foord.) + * The :mod:`unittest` module has two new methods, :meth:`~unittest.TestCase.assertWarns` and - :meth:`~unittest.TestCase.assertWarnsRegex` to check that a given warning type + :meth:`~unittest.TestCase.assertWarnsRegex` to verify that a given warning type is triggered by the code under test: >>> with self.assertWarns(DeprecationWarning): ... legacy_function('XYZ') + (Contributed by Michael Foord and Ezio Melotti.) + Another new method, :meth:`~unittest.TestCase.assertCountEqual` is used to compare two iterables to determine if their element counts are equal (whether the same elements are present with the same number of occurrences regardless @@ -1104,23 +1132,28 @@ unittest def test_anagram(self): self.assertCountEqual('algorithm', 'logarithm') - A principal feature of the unittest module is an effort to produce meaningful + (Contributed by Raymond Hettinger.) + +* A principal feature of the unittest module is an effort to produce meaningful diagnostics when a test fails. When possible the failure is recorded along with a diff of the output. This is especially helpful for analyzing log files of failed test runs. However, since diffs can sometime be voluminous, there is a new :attr:`~unittest.TestCase.maxDiff` attribute which sets maximum length of diffs. - In addition the naming in the module has undergone a number of clean-ups. For - example, :meth:`~unittest.TestCase.assertRegex` is the new name for +* In addition, the method names in the module have undergone a number of clean-ups. + + For example, :meth:`~unittest.TestCase.assertRegex` is the new name for :meth:`~unittest.TestCase.assertRegexpMatches` which was misnamed because the test uses :func:`re.search`, not :func:`re.match`. Other methods using - regular expressions are now named using short form "Regex" in preference - to "Regexp" -- this matches the names used in other unittest implementations, + regular expressions are now named using short form "Regex" in preference to + "Regexp" -- this matches the names used in other unittest implementations, matches Python's old name for the :mod:`re` module, and it has unambiguous camel-casing. - To improve consistency, some of long-standing method aliases are being + (Contributed by Raymond Hettinger and implemented by Ezio Melotti.) + +* To improve consistency, some of long-standing method aliases are being deprecated in favor of the preferred names: - replace :meth:`assert_` with :meth:`.assertTrue` @@ -1135,6 +1168,13 @@ unittest (Contributed by Ezio Melotti; :issue:`9424`.) +* The :meth:`~unittest.TestCase.assertDictContainsSubset` method was deprecated + because it was mis-implemented with the arguments in the wrong order. This + created hard-to-debug optical illusions where tests like + ``TestCase().assertDictContainsSubset({'a':1, 'b':2}, {'a':1})`` would fail. + + (Contributed by Raymond Hettinger.) + random ------ @@ -1548,12 +1588,22 @@ The :mod:`datetime` module now has an auxiliary implementation in pure Python. No functionality was changed. This just provides an easier-to-read alternate implementation. (Contributed by Alexander Belopolsky.) +The unmaintained *Demo* directory has been removed. Some demos were integrated +into the documentation, some were moved to the *Tools/demo* directory, and +others were removed altogether. (Contributed by Georg Brandl.) + IDLE ==== * The format menu now has an option to clean-up source files by stripping - trailing whitespace (:issue:`5150`). + trailing whitespace. + + (Contributed by Raymond Hettinger; :issue:`5150`.) + +* IDLE on Mac OS X now works with both Carbon AquaTk and Cocoa AquaTk. + + (Contributed by Kevin Walzer, Ned Deily, and Ronald Oussoren; :issue:`6075`.) Build and C API Changes @@ -1561,6 +1611,9 @@ Build and C API Changes Changes to Python's build process and to the C API include: +* The *idle*, *pydoc* and *2to3* scripts are now installed with a + version-specific suffix on ``make altinstall`` (:issue:`10679`). + * The C functions that access the Unicode Database now accept and return characters from the full Unicode range, even on narrow unicode builds (Py_UNICODE_TOLOWER, Py_UNICODE_ISDECIMAL, and others). A visible difference @@ -1713,6 +1766,13 @@ require changes to your code: (Contributed by Georg Brandl and Mattias Brändström; `appspot issue 53094 <http://codereview.appspot.com/53094>`_.) -* :func:`struct.pack` no longer implicitly encodes unicode to UTF-8: use - explicit conversion instead and replace unicode literals by bytes literals. +* :func:`struct.pack` now only allows bytes for the ``s`` string pack code. + Formerly, it would accept text arguments and implicitly encode them to bytes + using UTF-8. This was problematic because it made assumptions about the + correct encoding and because a variable length encoding can fail when writing + to fixed length segment of a structure. + + Code such as ``struct.pack('<6sHHBBB', 'GIF87a', x, y)`` should be rewritten + with to use bytes instead of text, ``struct.pack('<6sHHBBB', b'GIF87a', x, y)``. + (Discovered by David Beazley and fixed by Victor Stinner; :issue:`10783`. |