Add various items
This commit is contained in:
Andrew M. Kuchling
parent
915b1206f2
commit
5a9c40b21c
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@ -49,46 +49,191 @@
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This saves the maintainer some effort going through the SVN logs
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when researching a change.
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This article explains the new features in Python 2.7.
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No release schedule has been decided yet for 2.7.
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This article explains the new features in Python 2.7. No release
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schedule has been decided yet for 2.7; the schedule will eventually be
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described in :pep:`373`.
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.. Compare with previous release in 2 - 3 sentences here.
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add hyperlink when the documentation becomes available online.
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Python 3.1
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================
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.. _whatsnew27-python31:
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Python 3.1 Features
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=======================
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Much as Python 2.6 incorporated features from Python 3.0,
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version 2.7 is influenced by features from 3.1.
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version 2.7 incorporates some of the new features
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in Python 3.1. The 2.x series continues to provide tools
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for migrating to the 3.x series.
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XXX mention importlib; anything else?
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A partial list of 3.1 features that were backported to 2.7:
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* A version of the :mod:`io` library, rewritten in C for performance.
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* The ordered-dictionary type described in :ref:`pep-0372`.
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* The new format specified described in :ref:`pep-0378`.
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* The :class:`memoryview` object.
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* A small subset of the :mod:`importlib` module `described below <#importlib-section>`__.
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One porting change: the :option:`-3` switch now automatically
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enables the :option:`-Qwarn` switch that causes warnings
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about using classic division with integers and long integers.
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Other new Python3-mode warnings include:
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* :func:`operator.isCallable` and :func:`operator.sequenceIncludes`,
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which are not supported in 3.x.
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.. ========================================================================
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.. Large, PEP-level features and changes should be described here.
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.. ========================================================================
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.. _pep-0372:
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PEP 372: Adding an ordered dictionary to collections
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====================================================
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XXX write this
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Regular Python dictionaries iterate over key/value pairs in arbitrary order.
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Over the years, a number of authors have written alternative implementations
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that remember the order that the keys were originally inserted. Based on
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the experiences from those implementations, a new
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:class:`collections.OrderedDict` class has been introduced.
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Several modules will now use :class:`OrderedDict` by default. The
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:mod:`ConfigParser` module uses :class:`OrderedDict` for the list
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of sections and the options within a section.
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The :meth:`namedtuple._asdict` method returns an :class:`OrderedDict`
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as well.
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The :class:`OrderedDict` API is substantially the same as regular dictionaries
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but will iterate over keys and values in a guaranteed order depending on
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when a key was first inserted::
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>>> from collections import OrderedDict
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>>> d = OrderedDict([('first', 1), ('second', 2),
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... ('third', 3)])
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>>> d.items()
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[('first', 1), ('second', 2), ('third', 3)]
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If a new entry overwrites an existing entry, the original insertion
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position is left unchanged::
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>>> d['second'] = 4
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>>> d.items()
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[('first', 1), ('second', 4), ('third', 3)]
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Deleting an entry and reinserting it will move it to the end::
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>>> del d['second']
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>>> d['second'] = 5
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>>> d.items()
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[('first', 1), ('third', 3), ('second', 5)]
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The :meth:`popitem` method has an optional *last* argument
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that defaults to True. If *last* is True, the most recently
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added key is returned and removed; if it's False, the
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oldest key is selected::
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>>> od = OrderedDict([(x,0) for x in range(20)])
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>>> od.popitem()
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(19, 0)
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>>> od.popitem()
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(18, 0)
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>>> od.popitem(False)
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(0, 0)
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>>> od.popitem(False)
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(1, 0)
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Comparing two ordered dictionaries checks both the keys and values,
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and requires that the insertion order was the same::
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>>> od1 = OrderedDict([('first', 1), ('second', 2),
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... ('third', 3)])
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>>> od2 = OrderedDict([('third', 3), ('first', 1),
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... ('second', 2)])
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>>> od1==od2
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False
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>>> # Move 'third' key to the end
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>>> del od2['third'] ; od2['third'] = 3
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>>> od1==od2
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True
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Comparing an :class:`OrderedDict` with a regular dictionary
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ignores the insertion order and just compares the keys and values.
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How does the :class:`OrderedDict` work? It maintains a doubly-linked
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list of keys, appending new keys to the list as they're inserted. A
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secondary dictionary maps keys to their corresponding list node, so
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deletion doesn't have to traverse the entire linked list and therefore
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remains O(1).
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.. XXX check O(1)-ness with Raymond
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The standard library now supports use of ordered dictionaries in several
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modules. The :mod:`configparser` module uses them by default. This lets
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configuration files be read, modified, and then written back in their original
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order. The *_asdict()* method for :func:`collections.namedtuple` now
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returns an ordered dictionary with the values appearing in the same order as
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the underlying tuple indicies. The :mod:`json` module is being built-out with
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an *object_pairs_hook* to allow OrderedDicts to be built by the decoder.
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Support was also added for third-party tools like `PyYAML <http://pyyaml.org/>`_.
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.. _pep-0378:
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PEP 378: Format Specifier for Thousands Separator
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====================================================
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To make program output more readable, it can be useful to add
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separators to large numbers and render them as
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18,446,744,073,709,551,616 instead of 18446744073709551616.
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The fully general solution for doing this is the :mod:`locale` module,
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which can use different separators ("," in North America, "." in
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Europe) and different grouping sizes, but :mod:`locale` is complicated
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to use and unsuitable for multi-threaded applications where different
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threads are producing output for different locales.
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Therefore, a simple comma-grouping mechanism has been added to the
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mini-language used by the string :meth:`format` method. When
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formatting a floating-point number, simply include a comma between the
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width and the precision::
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>>> '{:20,.2}'.format(f)
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'18,446,744,073,709,551,616.00'
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This mechanism is not adaptable at all; commas are always used as the
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separator and the grouping is always into three-digit groups. The
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comma-formatting mechanism isn't as general as the :mod:`locale`
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module, but it's easier to use.
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.. XXX "Format String Syntax" in string.rst doesn't describe ',';
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could use many more examples.
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.. seealso::
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:pep:`378` - Format Specifier for Thousands Separator
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PEP written by Raymond Hettinger; implemented by Eric Smith.
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Other Language Changes
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======================
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Some smaller changes made to the core Python language are:
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* :meth:`str.format` method now supports automatic numbering of the replacement
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* The :keyword:`with` statement can now use multiple context managers
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in one statement. Context managers are processed from left to right
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and each one is treated as beginning a new :keyword:`with` statement.
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This means that::
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with A() as a, B() as b:
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... suite of statements ...
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is equivalent to::
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with A() as a:
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with B() as b:
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... suite of statements ...
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The :func:`contextlib.nested` function provides a very similar
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function, so it's no longer necessary and has been deprecated.
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(Proposed in http://codereview.appspot.com/53094; implemented by
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Georg Brandl.)
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* The :meth:`str.format` method now supports automatic numbering of the replacement
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fields. This makes using :meth:`str.format` more closely resemble using
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``%s`` formatting::
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@ -102,7 +247,13 @@ Some smaller changes made to the core Python language are:
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specifier will use the next argument, and so on. You can't mix auto-numbering
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and explicit numbering -- either number all of your specifier fields or none
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of them -- but you can mix auto-numbering and named fields, as in the second
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example above. (Contributed by Eric Smith; :issue`5237`.)
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example above. (Contributed by Eric Smith; :issue:`5237`.)
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Complex numbers now correctly support usage with :func:`format`.
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Specifying a precision or comma-separation applies to both the real
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and imaginary parts of the number, but a specified field width and
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alignment is applied to the whole of the resulting ``1.5+3j``
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output. (Contributed by Eric Smith; :issue:`1588`.)
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* The :func:`int` and :func:`long` types gained a ``bit_length``
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method that returns the number of bits necessary to represent
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@ -125,7 +276,7 @@ Some smaller changes made to the core Python language are:
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point now round differently, returning the floating-point number
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closest to the number. This doesn't matter for small integers that
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can be converted exactly, but for large numbers that will
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unavoidably lose precision, Python 2.7 will now approximate more
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unavoidably lose precision, Python 2.7 now approximates more
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closely. For example, Python 2.6 computed the following::
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>>> n = 295147905179352891391
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@ -146,10 +297,20 @@ Some smaller changes made to the core Python language are:
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(Implemented by Mark Dickinson; :issue:`3166`.)
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* The :class:`bytearray` type's :meth:`translate` method will
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now accept ``None`` as its first argument. (Fixed by Georg Brandl;
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* The :class:`bytearray` type's :meth:`translate` method now accepts
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``None`` as its first argument. (Fixed by Georg Brandl;
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:issue:`4759`.)
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* When using ``@classmethod`` and ``@staticmethod`` to wrap
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methods as class or static methods, the wrapper object now
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exposes the wrapped function as their :attr:`__func__` attribute.
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(Contributed by Amaury Forgeot d'Arc, after a suggestion by
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George Sakkis; :issue:`5982`.)
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* A new encoding named "cp720", used primarily for Arabic text, is now
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supported. (Contributed by Alexander Belchenko and Amaury Forgeot
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d'Arc; :issue:`1616979`.)
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.. ======================================================================
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@ -164,6 +325,10 @@ Several performance enhancements have been added:
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and benchmark. The new mechanism is only supported on certain
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compilers, such as gcc, SunPro, and icc.
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* A new opcode was added to perform the initial setup for
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:keyword:`with` statements, looking up the :meth:`__enter__` and
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:meth:`__exit__` methods. (Contributed by Benjamin Peterson.)
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* The garbage collector now performs better when many objects are
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being allocated without deallocating any. A full garbage collection
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pass is only performed when the middle generation has been collected
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@ -184,7 +349,7 @@ Several performance enhancements have been added:
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considered and traversed by the collector.
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(Contributed by Antoine Pitrou; :issue:`4688`.)
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* Integers are now stored internally either in base 2**15 or in base
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* Long integers are now stored internally either in base 2**15 or in base
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2**30, the base being determined at build time. Previously, they
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were always stored in base 2**15. Using base 2**30 gives
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significant performance improvements on 64-bit machines, but
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@ -227,6 +392,21 @@ Several performance enhancements have been added:
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faster bytecode. (Patch by Antoine Pitrou, back-ported to 2.7
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by Jeffrey Yasskin; :issue:`4715`.)
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* The :mod:`pickle` and :mod:`cPickle` modules now automatically
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intern the strings used for attribute names, reducing memory usage
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of the objects resulting from unpickling. (Contributed by Jake
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McGuire; :issue:`5084`.)
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* The :mod:`cPickle` module now special-cases dictionaries,
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nearly halving the time required to pickle them.
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(Contributed by Collin Winter; :issue:`5670`.)
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* Converting an integer or long integer to a decimal string was made
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faster by special-casing base 10 instead of using a generalized
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conversion function that supports arbitrary bases.
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(Patch by Gawain Bolton; :issue:`6713`.)
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.. ======================================================================
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New, Improved, and Deprecated Modules
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@ -238,6 +418,14 @@ changes, sorted alphabetically by module name. Consult the
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:file:`Misc/NEWS` file in the source tree for a more complete list of
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changes, or look through the Subversion logs for all the details.
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* The :mod:`bdb` module's base debugging class :class:`Bdb`
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gained a feature for skipping modules. The constructor
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now takes an iterable containing glob-style patterns such as
|
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``django.*``; the debugger will not step into stack frames
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from a module that matches one of these patterns.
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(Contributed by Maru Newby after a suggestion by
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Senthil Kumaran; :issue:`5142`.)
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* The :mod:`bz2` module's :class:`BZ2File` now supports the context
|
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management protocol, so you can write ``with bz2.BZ2File(...) as f: ...``.
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(Contributed by Hagen Fuerstenau; :issue:`3860`.)
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|
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@ -279,6 +467,9 @@ changes, or look through the Subversion logs for all the details.
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Contributed by Raymond Hettinger; :issue:`1696199`.
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The new `OrderedDict` class is described in the earlier section
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:ref:`pep-0372`.
|
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|
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The :class:`namedtuple` class now has an optional *rename* parameter.
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If *rename* is true, field names that are invalid because they've
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been repeated or that aren't legal Python identifiers will be
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@ -295,10 +486,42 @@ changes, or look through the Subversion logs for all the details.
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The :class:`deque` data type now exposes its maximum length as the
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read-only :attr:`maxlen` attribute. (Added by Raymond Hettinger.)
|
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|
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* In Distutils, :func:`distutils.sdist.add_defaults` now uses
|
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* The :mod:`ctypes` module now always converts ``None`` to a C NULL
|
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pointer for arguments declared as pointers. (Changed by Thomas
|
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Heller; :issue:`4606`.)
|
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|
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* New method: the :class:`Decimal` class gained a
|
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:meth:`from_float` class method that performs an exact conversion
|
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of a floating-point number to a :class:`Decimal`.
|
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Note that this is an **exact** conversion that strives for the
|
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closest decimal approximation to the floating-point representation's value;
|
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the resulting decimal value will therefore still include the inaccuracy,
|
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if any.
|
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For example, ``Decimal.from_float(0.1)`` returns
|
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``Decimal('0.1000000000000000055511151231257827021181583404541015625')``.
|
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(Implemented by Raymond Hettinger; :issue:`4796`.)
|
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|
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The constructor for :class:`Decimal` now accepts non-European
|
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Unicode characters, such as Arabic-Indic digits. (Contributed by
|
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Mark Dickinson; :issue:`6595`.)
|
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|
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When using :class:`Decimal` instances with a string's
|
||||
:meth:`format` method, the default alignment was previously
|
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left-alignment. This has been changed to right-alignment, which seems
|
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more sensible for numeric types. (Changed by Mark Dickinson; :issue:`6857`.)
|
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|
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* Distutils is being more actively developed, thanks to Tarek Ziade
|
||||
has taken over maintenance of the package. A new
|
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:file:`setup.py` subcommand, ``check``, will
|
||||
check that the arguments being passed to the :func:`setup` function
|
||||
are complete and correct (:issue:`5732`).
|
||||
|
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:func:`distutils.sdist.add_defaults` now uses
|
||||
*package_dir* and *data_files* to create the MANIFEST file.
|
||||
:mod:`distutils.sysconfig` will now read the :envvar:`AR`
|
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environment variable.
|
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:mod:`distutils.sysconfig` now reads the :envvar:`AR` and
|
||||
:envvar:`ARFLAGS` environment variables.
|
||||
|
||||
.. ARFLAGS done in #5941
|
||||
|
||||
It is no longer mandatory to store clear-text passwords in the
|
||||
:file:`.pypirc` file when registering and uploading packages to PyPI. As long
|
||||
|
|
@ -312,18 +535,7 @@ changes, or look through the Subversion logs for all the details.
|
|||
process, but instead simply not install the failing extension.
|
||||
(Contributed by Georg Brandl; :issue:`5583`.)
|
||||
|
||||
* New method: the :class:`Decimal` class gained a
|
||||
:meth:`from_float` class method that performs an exact conversion
|
||||
of a floating-point number to a :class:`Decimal`.
|
||||
Note that this is an **exact** conversion that strives for the
|
||||
closest decimal approximation to the floating-point representation's value;
|
||||
the resulting decimal value will therefore still include the inaccuracy,
|
||||
if any.
|
||||
For example, ``Decimal.from_float(0.1)`` returns
|
||||
``Decimal('0.1000000000000000055511151231257827021181583404541015625')``.
|
||||
(Implemented by Raymond Hettinger; :issue:`4796`.)
|
||||
|
||||
* The :class:`Fraction` class will now accept two rational numbers
|
||||
* The :class:`Fraction` class now accepts two rational numbers
|
||||
as arguments to its constructor.
|
||||
(Implemented by Mark Dickinson; :issue:`5812`.)
|
||||
|
||||
|
|
@ -338,7 +550,32 @@ changes, or look through the Subversion logs for all the details.
|
|||
recorded in a gzipped file by providing an optional timestamp to
|
||||
the constructor. (Contributed by Jacques Frechet; :issue:`4272`.)
|
||||
|
||||
* The :class:`io.FileIO` class now raises an :exc:`OSError` when passed
|
||||
* The :mod:`hashlib` module was inconsistent about accepting
|
||||
input as a Unicode object or an object that doesn't support
|
||||
the buffer protocol. The behavior was different depending on
|
||||
whether :mod:`hashlib` was using an external OpenSSL library
|
||||
or its built-in implementations. Python 2.7 makes the
|
||||
behavior consistent, always rejecting such objects by raising a
|
||||
:exc:`TypeError`. (Fixed by Gregory P. Smith; :issue:`3745`.)
|
||||
|
||||
* The default :class:`HTTPResponse` class used by the :mod:`httplib` module now
|
||||
supports buffering, resulting in much faster reading of HTTP responses.
|
||||
(Contributed by Kristjan Valur Jonsson; :issue:`4879`.)
|
||||
|
||||
* The :mod:`imaplib` module now supports IPv6 addresses.
|
||||
(Contributed by Derek Morr; :issue:`1655`.)
|
||||
|
||||
* The :mod:`io` library has been upgraded to the version shipped with
|
||||
Python 3.1. For 3.1, the I/O library was entirely rewritten in C
|
||||
and is 2 to 20 times faster depending on the task at hand. The
|
||||
original Python version was renamed to the :mod:`_pyio` module.
|
||||
|
||||
One minor resulting change: the :class:`io.TextIOBase` class now
|
||||
has an :attr:`errors` attribute giving the error setting
|
||||
used for encoding and decoding errors (one of ``'strict'``, ``'replace'``,
|
||||
``'ignore'``).
|
||||
|
||||
The :class:`io.FileIO` class now raises an :exc:`OSError` when passed
|
||||
an invalid file descriptor. (Implemented by Benjamin Peterson;
|
||||
:issue:`4991`.)
|
||||
|
||||
|
|
@ -382,12 +619,19 @@ changes, or look through the Subversion logs for all the details.
|
|||
with any object literal that decodes to a list of pairs.
|
||||
(Contributed by Raymond Hettinger; :issue:`5381`.)
|
||||
|
||||
* New functions: the :mod:`math` module now has
|
||||
a :func:`gamma` function.
|
||||
(Contributed by Mark Dickinson and nirinA raseliarison; :issue:`3366`.)
|
||||
|
||||
* The :mod:`multiprocessing` module's :class:`Manager*` classes
|
||||
can now be passed a callable that will be called whenever
|
||||
a subprocess is started, along with a set of arguments that will be
|
||||
passed to the callable.
|
||||
(Contributed by lekma; :issue:`5585`.)
|
||||
|
||||
* The :mod:`nntplib` module now supports IPv6 addresses.
|
||||
(Contributed by Derek Morr; :issue:`1664`.)
|
||||
|
||||
* The :mod:`pydoc` module now has help for the various symbols that Python
|
||||
uses. You can now do ``help('<<')`` or ``help('@')``, for example.
|
||||
(Contributed by David Laban; :issue:`4739`.)
|
||||
|
|
@ -396,6 +640,39 @@ changes, or look through the Subversion logs for all the details.
|
|||
now accept an optional *flags* argument, for consistency with the
|
||||
other functions in the module. (Added by Gregory P. Smith.)
|
||||
|
||||
* The :mod:`shutil` module's :func:`copyfile` and :func:`copytree`
|
||||
functions now raises a :exc:`SpecialFileError` exception when
|
||||
asked to copy a named pipe. Previously the code would treat
|
||||
named pipes like a regular file by opening them for reading, and
|
||||
this would block indefinitely. (Fixed by Antoine Pitrou; :issue:`3002`.)
|
||||
|
||||
* New functions: in the :mod:`site` module, three new functions
|
||||
return various site- and user-specific paths.
|
||||
:func:`getsitepackages` returns a list containing all
|
||||
global site-packages directories, and
|
||||
:func:`getusersitepackages` returns the path of the user's
|
||||
site-packages directory.
|
||||
:func:`getuserbase` returns the value of the :envvar:``USER_BASE``
|
||||
environment variable, giving the path to a directory that can be used
|
||||
to store data.
|
||||
(Contributed by Tarek Ziade; :issue:`6693`.)
|
||||
|
||||
* The :mod:`SocketServer` module's :class:`TCPServer` class now
|
||||
has a :attr:`disable_nagle_algorithm` class attribute.
|
||||
The default value is False; if overridden to be True,
|
||||
new request connections will have the TCP_NODELAY option set to
|
||||
prevent buffering many small sends into a single TCP packet.
|
||||
(Contributed by Kristjan Valur Jonsson; :issue:`6192`.)
|
||||
|
||||
.. XXX the documentation for this attr was silently dropped from
|
||||
.. Doc/library/socketserver.rst.
|
||||
|
||||
* The :mod:`struct` module will no longer silently ignore overflow
|
||||
errors when a value is too large for a particular integer format
|
||||
code (one of ``bBhHiIlLqQ``); it now always raises a
|
||||
:exc:`struct.error` exception. (Changed by Mark Dickinson;
|
||||
:issue:`1523`.)
|
||||
|
||||
* New function: the :mod:`subprocess` module's
|
||||
:func:`check_output` runs a command with a specified set of arguments
|
||||
and returns the command's output as a string when the command runs without
|
||||
|
|
@ -422,114 +699,25 @@ changes, or look through the Subversion logs for all the details.
|
|||
named ``major``, ``minor``, ``micro``, ``releaselevel``, and ``serial``.
|
||||
(Contributed by Ross Light; :issue:`4285`.)
|
||||
|
||||
* The :mod:`tarfile` module now supports filtering the :class:`TarInfo`
|
||||
objects being added to a tar file. When you call :meth:`TarFile.add`,
|
||||
instance, you may supply an optional *filter* argument
|
||||
that's a callable. The *filter* callable will be passed the
|
||||
:class:`TarInfo` for every file being added, and can modify and return it.
|
||||
If the callable returns ``None``, the file will be excluded from the
|
||||
resulting archive. This is more powerful than the existing
|
||||
*exclude* argument, which has therefore been deprecated.
|
||||
(Added by Lars Gustaebel; :issue:`6856`.)
|
||||
|
||||
* The :mod:`threading` module's :meth:`Event.wait` method now returns
|
||||
the internal flag on exit. This means the method will usually
|
||||
return true because :meth:`wait` is supposed to block until the
|
||||
internal flag becomes true. The return value will only be false if
|
||||
a timeout was provided and the operation timed out.
|
||||
(Contributed by XXX; :issue:`1674032`.)
|
||||
(Contributed by Tim Lesher; :issue:`1674032`.)
|
||||
|
||||
* The :mod:`unittest` module was enhanced in several ways.
|
||||
The progress messages will now show 'x' for expected failures
|
||||
and 'u' for unexpected successes when run in verbose mode.
|
||||
(Contributed by Benjamin Peterson.)
|
||||
Test cases can raise the :exc:`SkipTest` exception to skip a test.
|
||||
(:issue:`1034053`.)
|
||||
|
||||
The error messages for :meth:`assertEqual`,
|
||||
:meth:`assertTrue`, and :meth:`assertFalse`
|
||||
failures now provide more information. If you set the
|
||||
:attr:`longMessage` attribute of your :class:`TestCase` classes to
|
||||
true, both the standard error message and any additional message you
|
||||
provide will be printed for failures. (Added by Michael Foord; :issue:`5663`.)
|
||||
|
||||
The :meth:`assertRaises` and :meth:`failUnlessRaises` methods now
|
||||
return a context handler when called without providing a callable
|
||||
object to run. For example, you can write this::
|
||||
|
||||
with self.assertRaises(KeyError):
|
||||
raise ValueError
|
||||
|
||||
(Implemented by Antoine Pitrou; :issue:`4444`.)
|
||||
|
||||
The methods :meth:`addCleanup` and :meth:`doCleanups` were added.
|
||||
:meth:`addCleanup` allows you to add cleanup functions that
|
||||
will be called unconditionally (after :meth:`setUp` if
|
||||
:meth:`setUp` fails, otherwise after :meth:`tearDown`). This allows
|
||||
for much simpler resource allocation and deallocation during tests.
|
||||
:issue:`5679`
|
||||
|
||||
A number of new methods were added that provide more specialized
|
||||
tests. Many of these methods were written by Google engineers
|
||||
for use in their test suites; Gregory P. Smith, Michael Foord, and
|
||||
GvR worked on merging them into Python's version of :mod:`unittest`.
|
||||
|
||||
* :meth:`assertIsNone` and :meth:`assertIsNotNone` take one
|
||||
expression and verify that the result is or is not ``None``.
|
||||
|
||||
* :meth:`assertIs` and :meth:`assertIsNot` take two values and check
|
||||
whether the two values evaluate to the same object or not.
|
||||
(Added by Michael Foord; :issue:`2578`.)
|
||||
|
||||
* :meth:`assertGreater`, :meth:`assertGreaterEqual`,
|
||||
:meth:`assertLess`, and :meth:`assertLessEqual` compare
|
||||
two quantities.
|
||||
|
||||
* :meth:`assertMultiLineEqual` compares two strings, and if they're
|
||||
not equal, displays a helpful comparison that highlights the
|
||||
differences in the two strings.
|
||||
|
||||
* :meth:`assertRegexpMatches` checks whether its first argument is a
|
||||
string matching a regular expression provided as its second argument.
|
||||
|
||||
* :meth:`assertRaisesRegexp` checks whether a particular exception
|
||||
is raised, and then also checks that the string representation of
|
||||
the exception matches the provided regular expression.
|
||||
|
||||
* :meth:`assertIn` and :meth:`assertNotIn` tests whether
|
||||
*first* is or is not in *second*.
|
||||
|
||||
* :meth:`assertSameElements` tests whether two provided sequences
|
||||
contain the same elements.
|
||||
|
||||
* :meth:`assertSetEqual` compares whether two sets are equal, and
|
||||
only reports the differences between the sets in case of error.
|
||||
|
||||
* Similarly, :meth:`assertListEqual` and :meth:`assertTupleEqual`
|
||||
compare the specified types and explain the differences.
|
||||
More generally, :meth:`assertSequenceEqual` compares two sequences
|
||||
and can optionally check whether both sequences are of a
|
||||
particular type.
|
||||
|
||||
* :meth:`assertDictEqual` compares two dictionaries and reports the
|
||||
differences. :meth:`assertDictContainsSubset` checks whether
|
||||
all of the key/value pairs in *first* are found in *second*.
|
||||
|
||||
* :meth:`assertAlmostEqual` and :meth:`assertNotAlmostEqual` short-circuit
|
||||
(automatically pass or fail without checking decimal places) if the objects
|
||||
are equal.
|
||||
|
||||
* :meth:`loadTestsFromName` properly honors the ``suiteClass`` attribute of
|
||||
the :class:`TestLoader`. (Fixed by Mark Roddy; :issue:`6866`.)
|
||||
|
||||
* A new hook, :meth:`addTypeEqualityFunc` takes a type object and a
|
||||
function. The :meth:`assertEqual` method will use the function
|
||||
when both of the objects being compared are of the specified type.
|
||||
This function should compare the two objects and raise an
|
||||
exception if they don't match; it's a good idea for the function
|
||||
to provide additional information about why the two objects are
|
||||
matching, much as the new sequence comparison methods do.
|
||||
|
||||
:func:`unittest.main` now takes an optional ``exit`` argument.
|
||||
If False ``main`` doesn't call :func:`sys.exit` allowing it to
|
||||
be used from the interactive interpreter. :issue:`3379`.
|
||||
|
||||
:class:`TestResult` has new :meth:`startTestRun` and
|
||||
:meth:`stopTestRun` methods; called immediately before
|
||||
and after a test run. :issue:`5728` by Robert Collins.
|
||||
|
||||
* The :func:`is_zipfile` function in the :mod:`zipfile` module will now
|
||||
accept a file object, in addition to the path names accepted in earlier
|
||||
* The :func:`is_zipfile` function in the :mod:`zipfile` module now
|
||||
accepts a file object, in addition to the path names accepted in earlier
|
||||
versions. (Contributed by Gabriel Genellina; :issue:`4756`.)
|
||||
|
||||
:mod:`zipfile` now supports archiving empty directories and
|
||||
|
|
@ -538,6 +726,118 @@ changes, or look through the Subversion logs for all the details.
|
|||
.. ======================================================================
|
||||
.. whole new modules get described in subsections here
|
||||
|
||||
Unit Testing Enhancements
|
||||
---------------------------------
|
||||
|
||||
The :mod:`unittest` module was enhanced in several ways.
|
||||
The progress messages now shows 'x' for expected failures
|
||||
and 'u' for unexpected successes when run in verbose mode.
|
||||
(Contributed by Benjamin Peterson.)
|
||||
Test cases can raise the :exc:`SkipTest` exception to skip a test.
|
||||
(:issue:`1034053`.)
|
||||
|
||||
.. XXX describe test discovery (Contributed by Michael Foord; :issue:`6001`.)
|
||||
|
||||
The error messages for :meth:`assertEqual`,
|
||||
:meth:`assertTrue`, and :meth:`assertFalse`
|
||||
failures now provide more information. If you set the
|
||||
:attr:`longMessage` attribute of your :class:`TestCase` classes to
|
||||
true, both the standard error message and any additional message you
|
||||
provide will be printed for failures. (Added by Michael Foord; :issue:`5663`.)
|
||||
|
||||
The :meth:`assertRaises` and :meth:`failUnlessRaises` methods now
|
||||
return a context handler when called without providing a callable
|
||||
object to run. For example, you can write this::
|
||||
|
||||
with self.assertRaises(KeyError):
|
||||
raise ValueError
|
||||
|
||||
(Implemented by Antoine Pitrou; :issue:`4444`.)
|
||||
|
||||
The methods :meth:`addCleanup` and :meth:`doCleanups` were added.
|
||||
:meth:`addCleanup` allows you to add cleanup functions that
|
||||
will be called unconditionally (after :meth:`setUp` if
|
||||
:meth:`setUp` fails, otherwise after :meth:`tearDown`). This allows
|
||||
for much simpler resource allocation and deallocation during tests.
|
||||
:issue:`5679`
|
||||
|
||||
A number of new methods were added that provide more specialized
|
||||
tests. Many of these methods were written by Google engineers
|
||||
for use in their test suites; Gregory P. Smith, Michael Foord, and
|
||||
GvR worked on merging them into Python's version of :mod:`unittest`.
|
||||
|
||||
* :meth:`assertIsNone` and :meth:`assertIsNotNone` take one
|
||||
expression and verify that the result is or is not ``None``.
|
||||
|
||||
* :meth:`assertIs` and :meth:`assertIsNot` take two values and check
|
||||
whether the two values evaluate to the same object or not.
|
||||
(Added by Michael Foord; :issue:`2578`.)
|
||||
|
||||
* :meth:`assertGreater`, :meth:`assertGreaterEqual`,
|
||||
:meth:`assertLess`, and :meth:`assertLessEqual` compare
|
||||
two quantities.
|
||||
|
||||
* :meth:`assertMultiLineEqual` compares two strings, and if they're
|
||||
not equal, displays a helpful comparison that highlights the
|
||||
differences in the two strings.
|
||||
|
||||
* :meth:`assertRegexpMatches` checks whether its first argument is a
|
||||
string matching a regular expression provided as its second argument.
|
||||
|
||||
* :meth:`assertRaisesRegexp` checks whether a particular exception
|
||||
is raised, and then also checks that the string representation of
|
||||
the exception matches the provided regular expression.
|
||||
|
||||
* :meth:`assertIn` and :meth:`assertNotIn` tests whether
|
||||
*first* is or is not in *second*.
|
||||
|
||||
* :meth:`assertSameElements` tests whether two provided sequences
|
||||
contain the same elements.
|
||||
|
||||
* :meth:`assertSetEqual` compares whether two sets are equal, and
|
||||
only reports the differences between the sets in case of error.
|
||||
|
||||
* Similarly, :meth:`assertListEqual` and :meth:`assertTupleEqual`
|
||||
compare the specified types and explain the differences.
|
||||
More generally, :meth:`assertSequenceEqual` compares two sequences
|
||||
and can optionally check whether both sequences are of a
|
||||
particular type.
|
||||
|
||||
* :meth:`assertDictEqual` compares two dictionaries and reports the
|
||||
differences. :meth:`assertDictContainsSubset` checks whether
|
||||
all of the key/value pairs in *first* are found in *second*.
|
||||
|
||||
* :meth:`assertAlmostEqual` and :meth:`assertNotAlmostEqual` short-circuit
|
||||
(automatically pass or fail without checking decimal places) if the objects
|
||||
are equal.
|
||||
|
||||
* :meth:`loadTestsFromName` properly honors the ``suiteClass`` attribute of
|
||||
the :class:`TestLoader`. (Fixed by Mark Roddy; :issue:`6866`.)
|
||||
|
||||
* A new hook, :meth:`addTypeEqualityFunc` takes a type object and a
|
||||
function. The :meth:`assertEqual` method will use the function
|
||||
when both of the objects being compared are of the specified type.
|
||||
This function should compare the two objects and raise an
|
||||
exception if they don't match; it's a good idea for the function
|
||||
to provide additional information about why the two objects are
|
||||
matching, much as the new sequence comparison methods do.
|
||||
|
||||
:func:`unittest.main` now takes an optional ``exit`` argument.
|
||||
If False ``main`` doesn't call :func:`sys.exit` allowing it to
|
||||
be used from the interactive interpreter. :issue:`3379`.
|
||||
|
||||
:class:`TestResult` has new :meth:`startTestRun` and
|
||||
:meth:`stopTestRun` methods; called immediately before
|
||||
and after a test run. :issue:`5728` by Robert Collins.
|
||||
|
||||
With all these changes, the :file:`unittest.py` was becoming awkwardly
|
||||
large, so the module was turned into a package and the code split into
|
||||
several files (by Benjamin Peterson). This doesn't affect how the
|
||||
module is imported.
|
||||
|
||||
|
||||
.. _importlib-section:
|
||||
|
||||
importlib: Importing Modules
|
||||
------------------------------
|
||||
|
||||
|
|
@ -549,7 +849,7 @@ import process. Python 2.7 doesn't contain the complete
|
|||
:mod:`importlib` package, but instead has a tiny subset that contains
|
||||
a single function, :func:`import_module`.
|
||||
|
||||
``import_module(*name*, *package*=None)`` imports a module. *name* is
|
||||
``import_module(name, package=None)`` imports a module. *name* is
|
||||
a string containing the module or package's name. It's possible to do
|
||||
relative imports by providing a string that begins with a ``.``
|
||||
character, such as ``..utils.errors``. For relative imports, the
|
||||
|
|
@ -599,8 +899,8 @@ Build and C API Changes
|
|||
Changes to Python's build process and to the C API include:
|
||||
|
||||
* If you use the :file:`.gdbinit` file provided with Python,
|
||||
the "pyo" macro in the 2.7 version will now work when the thread being
|
||||
debugged doesn't hold the GIL; the macro will now acquire it before printing.
|
||||
the "pyo" macro in the 2.7 version now works correctly when the thread being
|
||||
debugged doesn't hold the GIL; the macro now acquires it before printing.
|
||||
(Contributed by Victor Stinner; :issue:`3632`.)
|
||||
|
||||
* :cfunc:`Py_AddPendingCall` is now thread-safe, letting any
|
||||
|
|
@ -608,8 +908,57 @@ Changes to Python's build process and to the C API include:
|
|||
is particularly useful for asynchronous IO operations.
|
||||
(Contributed by Kristjan Valur Jonsson; :issue:`4293`.)
|
||||
|
||||
* New function: :cfunc:`PyCode_NewEmpty` creates an empty code object;
|
||||
only the filename, function name, and first line number are required.
|
||||
This is useful to extension modules that are attempting to
|
||||
construct a more useful traceback stack. Previously such
|
||||
extensions needed to call :cfunc:`PyCode_New`, which had many
|
||||
more arguments. (Added by Jeffrey Yasskin.)
|
||||
|
||||
* New function: :cfunc:`PyFrame_GetLineNumber` takes a frame object
|
||||
and returns the line number that the frame is currently executing.
|
||||
Previously code would need to get the index of the bytecode
|
||||
instruction currently executing, and then look up the line number
|
||||
corresponding to that address. (Added by Jeffrey Yasskin.)
|
||||
|
||||
* New macros: the Python header files now define the following macros:
|
||||
:cmacro:`Py_ISALNUM`,
|
||||
:cmacro:`Py_ISALPHA`,
|
||||
:cmacro:`Py_ISDIGIT`,
|
||||
:cmacro:`Py_ISLOWER`,
|
||||
:cmacro:`Py_ISSPACE`,
|
||||
:cmacro:`Py_ISUPPER`,
|
||||
:cmacro:`Py_ISXDIGIT`,
|
||||
and :cmacro:`Py_TOLOWER`, :cmacro:`Py_TOUPPER`.
|
||||
All of these functions are analogous to the C
|
||||
standard macros for classifying characters, but ignore the current
|
||||
locale setting, because in
|
||||
several places Python needs to analyze characters in a
|
||||
locale-independent way. (Added by Eric Smith;
|
||||
:issue:`5793`.)
|
||||
|
||||
.. XXX these macros don't seem to be described in the c-api docs.
|
||||
|
||||
* The complicated interaction between threads and process forking has
|
||||
been changed. Previously, the child process created by
|
||||
:func:`os.fork` might fail because the child is created with only a
|
||||
single thread running, the thread performing the :func:`os.fork`.
|
||||
If other threads were holding a lock, such as Python's import lock,
|
||||
when the fork was performed, the lock would still be marked as
|
||||
"held" in the new process. But in the child process nothing would
|
||||
ever release the lock, since the other threads weren't replicated,
|
||||
and the child process would no longer be able to perform imports.
|
||||
|
||||
Python 2.7 now acquires the import lock before performing an
|
||||
:func:`os.fork`, and will also clean up any locks created using the
|
||||
:mod:`threading` module. C extension modules that have internal
|
||||
locks, or that call :cfunc:`fork()` themselves, will not benefit
|
||||
from this clean-up.
|
||||
|
||||
(Fixed by Thomas Wouters; :issue:`1590864`.)
|
||||
|
||||
* Global symbols defined by the :mod:`ctypes` module are now prefixed
|
||||
with ``Py`, or with ``_ctypes``. (Implemented by Thomas
|
||||
with ``Py``, or with ``_ctypes``. (Implemented by Thomas
|
||||
Heller; :issue:`3102`.)
|
||||
|
||||
* The :program:`configure` script now checks for floating-point rounding bugs
|
||||
|
|
@ -618,6 +967,12 @@ Changes to Python's build process and to the C API include:
|
|||
but it's available if anyone wishes to use it.
|
||||
(Added by Mark Dickinson; :issue:`2937`.)
|
||||
|
||||
* The build process now creates the necessary files for pkg-config
|
||||
support. (Contributed by Clinton Roy; :issue:`3585`.)
|
||||
|
||||
* The build process now supports Subversion 1.7. (Contributed by
|
||||
Arfrever Frehtes Taifersar Arahesis; :issue:`6094`.)
|
||||
|
||||
.. ======================================================================
|
||||
|
||||
Port-Specific Changes: Windows
|
||||
|
|
@ -634,12 +989,15 @@ Port-Specific Changes: Windows
|
|||
the native thread-local storage functions are now used.
|
||||
(Contributed by Kristjan Valur Jonsson; :issue:`3582`.)
|
||||
|
||||
* The :func:`os.listdir` function now correctly fails
|
||||
for an empty path. (Fixed by Hirokazu Yamamoto; :issue:`5913`.)
|
||||
|
||||
.. ======================================================================
|
||||
|
||||
Port-Specific Changes: Mac OS X
|
||||
-----------------------------------
|
||||
|
||||
* The ``/Library/Python/2.7/site-packages`` is now appended to
|
||||
* The path ``/Library/Python/2.7/site-packages`` is now appended to
|
||||
``sys.path``, in order to share added packages between the system
|
||||
installation and a user-installed copy of the same version.
|
||||
(Changed by Ronald Oussoren; :issue:`4865`.)
|
||||
|
|
@ -658,12 +1016,12 @@ Other Changes and Fixes
|
|||
* The :file:`regrtest.py` script now takes a :option:`--randseed=`
|
||||
switch that takes an integer that will be used as the random seed
|
||||
for the :option:`-r` option that executes tests in random order.
|
||||
The :option:`-r` option also now reports the seed that was used
|
||||
The :option:`-r` option also reports the seed that was used
|
||||
(Added by Collin Winter.)
|
||||
|
||||
* The :file:`regrtest.py` script now takes a :option:`-j` switch
|
||||
that takes an integer specifying how many tests run in parallel. This
|
||||
allows to shorten the total runtime on multi-core machines.
|
||||
allows reducing the total runtime on multi-core machines.
|
||||
This option is compatible with several other options, including the
|
||||
:option:`-R` switch which is known to produce long runtimes.
|
||||
(Added by Antoine Pitrou, :issue:`6152`.)
|
||||
|
|
@ -676,6 +1034,17 @@ Porting to Python 2.7
|
|||
This section lists previously described changes and other bugfixes
|
||||
that may require changes to your code:
|
||||
|
||||
* When using :class:`Decimal` instances with a string's
|
||||
:meth:`format` method, the default alignment was previously
|
||||
left-alignment. This has been changed to right-alignment, which might
|
||||
change the output of your programs.
|
||||
(Changed by Mark Dickinson; :issue:`6857`.)
|
||||
|
||||
Another :meth:`format`-related change: the default precision used
|
||||
for floating-point and complex numbers was changed from 6 decimal
|
||||
places to 12, which matches the precision used by :func:`str`.
|
||||
(Changed by Eric Smith; :issue:`5920`.)
|
||||
|
||||
* Because of an optimization for the :keyword:`with` statement, the special
|
||||
methods :meth:`__enter__` and :meth:`__exit__` must belong to the object's
|
||||
type, and cannot be directly attached to the object's instance. This
|
||||
|
|
|
|||
Loading…
Reference in New Issue