diff options
Diffstat (limited to 'Doc/library')
36 files changed, 855 insertions, 321 deletions
diff --git a/Doc/library/annotationlib.rst b/Doc/library/annotationlib.rst index 41c9ce479ff..7dfc11449a6 100644 --- a/Doc/library/annotationlib.rst +++ b/Doc/library/annotationlib.rst @@ -211,6 +211,10 @@ Classes means may not have any information about their scope, so passing arguments to this method may be necessary to evaluate them successfully. + If no *owner*, *globals*, *locals*, or *type_params* are provided and the + :class:`~ForwardRef` does not contain information about its origin, + empty globals and locals dictionaries are used. + .. versionadded:: 3.14 diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst index 29396c7a036..17f126cc065 100644 --- a/Doc/library/argparse.rst +++ b/Doc/library/argparse.rst @@ -2122,12 +2122,15 @@ Partial parsing .. method:: ArgumentParser.parse_known_args(args=None, namespace=None) - Sometimes a script may only parse a few of the command-line arguments, passing - the remaining arguments on to another script or program. In these cases, the - :meth:`~ArgumentParser.parse_known_args` method can be useful. It works much like - :meth:`~ArgumentParser.parse_args` except that it does not produce an error when - extra arguments are present. Instead, it returns a two item tuple containing - the populated namespace and the list of remaining argument strings. + Sometimes a script only needs to handle a specific set of command-line + arguments, leaving any unrecognized arguments for another script or program. + In these cases, the :meth:`~ArgumentParser.parse_known_args` method can be + useful. + + This method works similarly to :meth:`~ArgumentParser.parse_args`, but it does + not raise an error for extra, unrecognized arguments. Instead, it parses the + known arguments and returns a two item tuple that contains the populated + namespace and the list of any unrecognized arguments. :: diff --git a/Doc/library/ast.rst b/Doc/library/ast.rst index ca9a6b0712c..ef6c62dca1e 100644 --- a/Doc/library/ast.rst +++ b/Doc/library/ast.rst @@ -252,12 +252,11 @@ Root nodes >>> print(ast.dump(ast.parse('(int, str) -> List[int]', mode='func_type'), indent=4)) FunctionType( argtypes=[ - Name(id='int', ctx=Load()), - Name(id='str', ctx=Load())], + Name(id='int'), + Name(id='str')], returns=Subscript( - value=Name(id='List', ctx=Load()), - slice=Name(id='int', ctx=Load()), - ctx=Load())) + value=Name(id='List'), + slice=Name(id='int'))) .. versionadded:: 3.8 @@ -268,9 +267,9 @@ Literals .. class:: Constant(value) A constant value. The ``value`` attribute of the ``Constant`` literal contains the - Python object it represents. The values represented can be simple types - such as a number, string or ``None``, but also immutable container types - (tuples and frozensets) if all of their elements are constant. + Python object it represents. The values represented can be instances of :class:`str`, + :class:`bytes`, :class:`int`, :class:`float`, :class:`complex`, and :class:`bool`, + and the constants :data:`None` and :data:`Ellipsis`. .. doctest:: @@ -312,14 +311,14 @@ Literals values=[ Constant(value='sin('), FormattedValue( - value=Name(id='a', ctx=Load()), + value=Name(id='a'), conversion=-1), Constant(value=') is '), FormattedValue( value=Call( - func=Name(id='sin', ctx=Load()), + func=Name(id='sin'), args=[ - Name(id='a', ctx=Load())]), + Name(id='a')]), conversion=-1, format_spec=JoinedStr( values=[ @@ -341,16 +340,14 @@ Literals elts=[ Constant(value=1), Constant(value=2), - Constant(value=3)], - ctx=Load())) + Constant(value=3)])) >>> print(ast.dump(ast.parse('(1, 2, 3)', mode='eval'), indent=4)) Expression( body=Tuple( elts=[ Constant(value=1), Constant(value=2), - Constant(value=3)], - ctx=Load())) + Constant(value=3)])) .. class:: Set(elts) @@ -388,7 +385,7 @@ Literals None], values=[ Constant(value=1), - Name(id='d', ctx=Load())])) + Name(id='d')])) Variables @@ -414,7 +411,7 @@ Variables Module( body=[ Expr( - value=Name(id='a', ctx=Load()))]) + value=Name(id='a'))]) >>> print(ast.dump(ast.parse('a = 1'), indent=4)) Module( @@ -452,7 +449,7 @@ Variables value=Name(id='b', ctx=Store()), ctx=Store())], ctx=Store())], - value=Name(id='it', ctx=Load()))]) + value=Name(id='it'))]) .. _ast-expressions: @@ -475,7 +472,7 @@ Expressions Expr( value=UnaryOp( op=USub(), - operand=Name(id='a', ctx=Load())))]) + operand=Name(id='a')))]) .. class:: UnaryOp(op, operand) @@ -498,7 +495,7 @@ Expressions Expression( body=UnaryOp( op=Not(), - operand=Name(id='x', ctx=Load()))) + operand=Name(id='x'))) .. class:: BinOp(left, op, right) @@ -511,9 +508,9 @@ Expressions >>> print(ast.dump(ast.parse('x + y', mode='eval'), indent=4)) Expression( body=BinOp( - left=Name(id='x', ctx=Load()), + left=Name(id='x'), op=Add(), - right=Name(id='y', ctx=Load()))) + right=Name(id='y'))) .. class:: Add @@ -549,8 +546,8 @@ Expressions body=BoolOp( op=Or(), values=[ - Name(id='x', ctx=Load()), - Name(id='y', ctx=Load())])) + Name(id='x'), + Name(id='y')])) .. class:: And @@ -575,7 +572,7 @@ Expressions LtE(), Lt()], comparators=[ - Name(id='a', ctx=Load()), + Name(id='a'), Constant(value=10)])) @@ -609,18 +606,17 @@ Expressions >>> print(ast.dump(ast.parse('func(a, b=c, *d, **e)', mode='eval'), indent=4)) Expression( body=Call( - func=Name(id='func', ctx=Load()), + func=Name(id='func'), args=[ - Name(id='a', ctx=Load()), + Name(id='a'), Starred( - value=Name(id='d', ctx=Load()), - ctx=Load())], + value=Name(id='d'))], keywords=[ keyword( arg='b', - value=Name(id='c', ctx=Load())), + value=Name(id='c')), keyword( - value=Name(id='e', ctx=Load()))])) + value=Name(id='e'))])) .. class:: keyword(arg, value) @@ -639,9 +635,9 @@ Expressions >>> print(ast.dump(ast.parse('a if b else c', mode='eval'), indent=4)) Expression( body=IfExp( - test=Name(id='b', ctx=Load()), - body=Name(id='a', ctx=Load()), - orelse=Name(id='c', ctx=Load()))) + test=Name(id='b'), + body=Name(id='a'), + orelse=Name(id='c'))) .. class:: Attribute(value, attr, ctx) @@ -656,9 +652,8 @@ Expressions >>> print(ast.dump(ast.parse('snake.colour', mode='eval'), indent=4)) Expression( body=Attribute( - value=Name(id='snake', ctx=Load()), - attr='colour', - ctx=Load())) + value=Name(id='snake'), + attr='colour')) .. class:: NamedExpr(target, value) @@ -694,15 +689,13 @@ Subscripting >>> print(ast.dump(ast.parse('l[1:2, 3]', mode='eval'), indent=4)) Expression( body=Subscript( - value=Name(id='l', ctx=Load()), + value=Name(id='l'), slice=Tuple( elts=[ Slice( lower=Constant(value=1), upper=Constant(value=2)), - Constant(value=3)], - ctx=Load()), - ctx=Load())) + Constant(value=3)]))) .. class:: Slice(lower, upper, step) @@ -716,11 +709,10 @@ Subscripting >>> print(ast.dump(ast.parse('l[1:2]', mode='eval'), indent=4)) Expression( body=Subscript( - value=Name(id='l', ctx=Load()), + value=Name(id='l'), slice=Slice( lower=Constant(value=1), - upper=Constant(value=2)), - ctx=Load())) + upper=Constant(value=2)))) Comprehensions @@ -745,11 +737,11 @@ Comprehensions ... )) Expression( body=ListComp( - elt=Name(id='x', ctx=Load()), + elt=Name(id='x'), generators=[ comprehension( target=Name(id='x', ctx=Store()), - iter=Name(id='numbers', ctx=Load()), + iter=Name(id='numbers'), is_async=0)])) >>> print(ast.dump( ... ast.parse('{x: x**2 for x in numbers}', mode='eval'), @@ -757,15 +749,15 @@ Comprehensions ... )) Expression( body=DictComp( - key=Name(id='x', ctx=Load()), + key=Name(id='x'), value=BinOp( - left=Name(id='x', ctx=Load()), + left=Name(id='x'), op=Pow(), right=Constant(value=2)), generators=[ comprehension( target=Name(id='x', ctx=Store()), - iter=Name(id='numbers', ctx=Load()), + iter=Name(id='numbers'), is_async=0)])) >>> print(ast.dump( ... ast.parse('{x for x in numbers}', mode='eval'), @@ -773,11 +765,11 @@ Comprehensions ... )) Expression( body=SetComp( - elt=Name(id='x', ctx=Load()), + elt=Name(id='x'), generators=[ comprehension( target=Name(id='x', ctx=Store()), - iter=Name(id='numbers', ctx=Load()), + iter=Name(id='numbers'), is_async=0)])) @@ -798,17 +790,17 @@ Comprehensions Expression( body=ListComp( elt=Call( - func=Name(id='ord', ctx=Load()), + func=Name(id='ord'), args=[ - Name(id='c', ctx=Load())]), + Name(id='c')]), generators=[ comprehension( target=Name(id='line', ctx=Store()), - iter=Name(id='file', ctx=Load()), + iter=Name(id='file'), is_async=0), comprehension( target=Name(id='c', ctx=Store()), - iter=Name(id='line', ctx=Load()), + iter=Name(id='line'), is_async=0)])) >>> print(ast.dump(ast.parse('(n**2 for n in it if n>5 if n<10)', mode='eval'), @@ -816,22 +808,22 @@ Comprehensions Expression( body=GeneratorExp( elt=BinOp( - left=Name(id='n', ctx=Load()), + left=Name(id='n'), op=Pow(), right=Constant(value=2)), generators=[ comprehension( target=Name(id='n', ctx=Store()), - iter=Name(id='it', ctx=Load()), + iter=Name(id='it'), ifs=[ Compare( - left=Name(id='n', ctx=Load()), + left=Name(id='n'), ops=[ Gt()], comparators=[ Constant(value=5)]), Compare( - left=Name(id='n', ctx=Load()), + left=Name(id='n'), ops=[ Lt()], comparators=[ @@ -842,11 +834,11 @@ Comprehensions ... indent=4)) # Async comprehension Expression( body=ListComp( - elt=Name(id='i', ctx=Load()), + elt=Name(id='i'), generators=[ comprehension( target=Name(id='i', ctx=Store()), - iter=Name(id='soc', ctx=Load()), + iter=Name(id='soc'), is_async=1)])) @@ -888,7 +880,7 @@ Statements Name(id='a', ctx=Store()), Name(id='b', ctx=Store())], ctx=Store())], - value=Name(id='c', ctx=Load()))]) + value=Name(id='c'))]) .. class:: AnnAssign(target, annotation, value, simple) @@ -911,7 +903,7 @@ Statements body=[ AnnAssign( target=Name(id='c', ctx=Store()), - annotation=Name(id='int', ctx=Load()), + annotation=Name(id='int'), simple=1)]) >>> print(ast.dump(ast.parse('(a): int = 1'), indent=4)) # Annotation with parenthesis @@ -919,7 +911,7 @@ Statements body=[ AnnAssign( target=Name(id='a', ctx=Store()), - annotation=Name(id='int', ctx=Load()), + annotation=Name(id='int'), value=Constant(value=1), simple=0)]) @@ -928,10 +920,10 @@ Statements body=[ AnnAssign( target=Attribute( - value=Name(id='a', ctx=Load()), + value=Name(id='a'), attr='b', ctx=Store()), - annotation=Name(id='int', ctx=Load()), + annotation=Name(id='int'), simple=0)]) >>> print(ast.dump(ast.parse('a[1]: int'), indent=4)) # Subscript annotation @@ -939,10 +931,10 @@ Statements body=[ AnnAssign( target=Subscript( - value=Name(id='a', ctx=Load()), + value=Name(id='a'), slice=Constant(value=1), ctx=Store()), - annotation=Name(id='int', ctx=Load()), + annotation=Name(id='int'), simple=0)]) @@ -979,8 +971,8 @@ Statements Module( body=[ Raise( - exc=Name(id='x', ctx=Load()), - cause=Name(id='y', ctx=Load()))]) + exc=Name(id='x'), + cause=Name(id='y'))]) .. class:: Assert(test, msg) @@ -994,8 +986,8 @@ Statements Module( body=[ Assert( - test=Name(id='x', ctx=Load()), - msg=Name(id='y', ctx=Load()))]) + test=Name(id='x'), + msg=Name(id='y'))]) .. class:: Delete(targets) @@ -1041,7 +1033,7 @@ Statements body=[ TypeAlias( name=Name(id='Alias', ctx=Store()), - value=Name(id='int', ctx=Load()))]) + value=Name(id='int'))]) .. versionadded:: 3.12 @@ -1134,13 +1126,13 @@ Control flow Module( body=[ If( - test=Name(id='x', ctx=Load()), + test=Name(id='x'), body=[ Expr( value=Constant(value=Ellipsis))], orelse=[ If( - test=Name(id='y', ctx=Load()), + test=Name(id='y'), body=[ Expr( value=Constant(value=Ellipsis))], @@ -1174,7 +1166,7 @@ Control flow body=[ For( target=Name(id='x', ctx=Store()), - iter=Name(id='y', ctx=Load()), + iter=Name(id='y'), body=[ Expr( value=Constant(value=Ellipsis))], @@ -1199,7 +1191,7 @@ Control flow Module( body=[ While( - test=Name(id='x', ctx=Load()), + test=Name(id='x'), body=[ Expr( value=Constant(value=Ellipsis))], @@ -1227,11 +1219,11 @@ Control flow body=[ For( target=Name(id='a', ctx=Store()), - iter=Name(id='b', ctx=Load()), + iter=Name(id='b'), body=[ If( test=Compare( - left=Name(id='a', ctx=Load()), + left=Name(id='a'), ops=[ Gt()], comparators=[ @@ -1269,12 +1261,12 @@ Control flow value=Constant(value=Ellipsis))], handlers=[ ExceptHandler( - type=Name(id='Exception', ctx=Load()), + type=Name(id='Exception'), body=[ Expr( value=Constant(value=Ellipsis))]), ExceptHandler( - type=Name(id='OtherException', ctx=Load()), + type=Name(id='OtherException'), name='e', body=[ Expr( @@ -1309,7 +1301,7 @@ Control flow value=Constant(value=Ellipsis))], handlers=[ ExceptHandler( - type=Name(id='Exception', ctx=Load()), + type=Name(id='Exception'), body=[ Expr( value=Constant(value=Ellipsis))])])]) @@ -1337,12 +1329,12 @@ Control flow body=[ Expr( value=BinOp( - left=Name(id='a', ctx=Load()), + left=Name(id='a'), op=Add(), right=Constant(value=1)))], handlers=[ ExceptHandler( - type=Name(id='TypeError', ctx=Load()), + type=Name(id='TypeError'), body=[ Pass()])])]) @@ -1375,18 +1367,18 @@ Control flow With( items=[ withitem( - context_expr=Name(id='a', ctx=Load()), + context_expr=Name(id='a'), optional_vars=Name(id='b', ctx=Store())), withitem( - context_expr=Name(id='c', ctx=Load()), + context_expr=Name(id='c'), optional_vars=Name(id='d', ctx=Store()))], body=[ Expr( value=Call( - func=Name(id='something', ctx=Load()), + func=Name(id='something'), args=[ - Name(id='b', ctx=Load()), - Name(id='d', ctx=Load())]))])]) + Name(id='b'), + Name(id='d')]))])]) Pattern matching @@ -1426,14 +1418,14 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchSequence( patterns=[ MatchAs(name='x')]), guard=Compare( - left=Name(id='x', ctx=Load()), + left=Name(id='x'), ops=[ Gt()], comparators=[ @@ -1443,7 +1435,7 @@ Pattern matching value=Constant(value=Ellipsis))]), match_case( pattern=MatchClass( - cls=Name(id='tuple', ctx=Load())), + cls=Name(id='tuple')), body=[ Expr( value=Constant(value=Ellipsis))])])]) @@ -1467,7 +1459,7 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchValue( @@ -1494,7 +1486,7 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchSingleton(value=None), @@ -1521,7 +1513,7 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchSequence( @@ -1554,7 +1546,7 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchSequence( @@ -1603,7 +1595,7 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchMapping( @@ -1653,11 +1645,11 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchClass( - cls=Name(id='Point2D', ctx=Load()), + cls=Name(id='Point2D'), patterns=[ MatchValue( value=Constant(value=0)), @@ -1668,7 +1660,7 @@ Pattern matching value=Constant(value=Ellipsis))]), match_case( pattern=MatchClass( - cls=Name(id='Point3D', ctx=Load()), + cls=Name(id='Point3D'), kwd_attrs=[ 'x', 'y', @@ -1709,7 +1701,7 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchAs( @@ -1746,7 +1738,7 @@ Pattern matching Module( body=[ Match( - subject=Name(id='x', ctx=Load()), + subject=Name(id='x'), cases=[ match_case( pattern=MatchOr( @@ -1786,7 +1778,7 @@ Type annotations body=[ AnnAssign( target=Name(id='x', ctx=Store()), - annotation=Name(id='bool', ctx=Load()), + annotation=Name(id='bool'), value=Constant(value=1), simple=1)], type_ignores=[ @@ -1824,12 +1816,11 @@ aliases. type_params=[ TypeVar( name='T', - bound=Name(id='int', ctx=Load()), - default_value=Name(id='bool', ctx=Load()))], + bound=Name(id='int'), + default_value=Name(id='bool'))], value=Subscript( - value=Name(id='list', ctx=Load()), - slice=Name(id='T', ctx=Load()), - ctx=Load()))]) + value=Name(id='list'), + slice=Name(id='T')))]) .. versionadded:: 3.12 @@ -1854,17 +1845,14 @@ aliases. name='P', default_value=List( elts=[ - Name(id='int', ctx=Load()), - Name(id='str', ctx=Load())], - ctx=Load()))], + Name(id='int'), + Name(id='str')]))], value=Subscript( - value=Name(id='Callable', ctx=Load()), + value=Name(id='Callable'), slice=Tuple( elts=[ - Name(id='P', ctx=Load()), - Name(id='int', ctx=Load())], - ctx=Load()), - ctx=Load()))]) + Name(id='P'), + Name(id='int')])))]) .. versionadded:: 3.12 @@ -1885,18 +1873,13 @@ aliases. TypeAlias( name=Name(id='Alias', ctx=Store()), type_params=[ - TypeVarTuple( - name='Ts', - default_value=Tuple(ctx=Load()))], + TypeVarTuple(name='Ts', default_value=Tuple())], value=Subscript( - value=Name(id='tuple', ctx=Load()), + value=Name(id='tuple'), slice=Tuple( elts=[ Starred( - value=Name(id='Ts', ctx=Load()), - ctx=Load())], - ctx=Load()), - ctx=Load()))]) + value=Name(id='Ts'))])))]) .. versionadded:: 3.12 @@ -2001,8 +1984,8 @@ Function and class definitions body=[ Pass()], decorator_list=[ - Name(id='decorator1', ctx=Load()), - Name(id='decorator2', ctx=Load())], + Name(id='decorator1'), + Name(id='decorator2')], returns=Constant(value='return annotation'))]) @@ -2032,14 +2015,14 @@ Function and class definitions body=[ Expr( value=Yield( - value=Name(id='x', ctx=Load())))]) + value=Name(id='x')))]) >>> print(ast.dump(ast.parse('yield from x'), indent=4)) Module( body=[ Expr( value=YieldFrom( - value=Name(id='x', ctx=Load())))]) + value=Name(id='x')))]) .. class:: Global(names) @@ -2094,17 +2077,17 @@ Function and class definitions ClassDef( name='Foo', bases=[ - Name(id='base1', ctx=Load()), - Name(id='base2', ctx=Load())], + Name(id='base1'), + Name(id='base2')], keywords=[ keyword( arg='metaclass', - value=Name(id='meta', ctx=Load()))], + value=Name(id='meta'))], body=[ Pass()], decorator_list=[ - Name(id='decorator1', ctx=Load()), - Name(id='decorator2', ctx=Load())])]) + Name(id='decorator1'), + Name(id='decorator2')])]) .. versionchanged:: 3.12 Added ``type_params``. @@ -2141,7 +2124,7 @@ Async and await Expr( value=Await( value=Call( - func=Name(id='other_func', ctx=Load()))))])]) + func=Name(id='other_func'))))])]) .. class:: AsyncFor(target, iter, body, orelse, type_comment) @@ -2402,7 +2385,7 @@ and classes for traversing abstract syntax trees: def visit_Name(self, node): return Subscript( - value=Name(id='data', ctx=Load()), + value=Name(id='data'), slice=Constant(value=node.id), ctx=node.ctx ) @@ -2445,8 +2428,26 @@ and classes for traversing abstract syntax trees: indents that many spaces per level. If *indent* is a string (such as ``"\t"``), that string is used to indent each level. - If *show_empty* is ``False`` (the default), empty lists and fields that are ``None`` - will be omitted from the output. + If *show_empty* is false (the default), optional empty lists and + ``Load()`` values will be omitted from the output. + Optional ``None`` values are always omitted. + + .. doctest:: + + >>> tree = ast.parse('print(None)', '?', 'eval') + >>> print(ast.dump(tree, indent=4)) + Expression( + body=Call( + func=Name(id='print'), + args=[ + Constant(value=None)])) + >>> print(ast.dump(tree, indent=4, show_empty=True)) + Expression( + body=Call( + func=Name(id='print', ctx=Load()), + args=[ + Constant(value=None)], + keywords=[])) .. versionchanged:: 3.9 Added the *indent* option. @@ -2454,32 +2455,8 @@ and classes for traversing abstract syntax trees: .. versionchanged:: 3.13 Added the *show_empty* option. - .. doctest:: - - >>> print(ast.dump(ast.parse("""\ - ... async def f(): - ... await other_func() - ... """), indent=4, show_empty=True)) - Module( - body=[ - AsyncFunctionDef( - name='f', - args=arguments( - posonlyargs=[], - args=[], - kwonlyargs=[], - kw_defaults=[], - defaults=[]), - body=[ - Expr( - value=Await( - value=Call( - func=Name(id='other_func', ctx=Load()), - args=[], - keywords=[])))], - decorator_list=[], - type_params=[])], - type_ignores=[]) + .. versionchanged:: next + Omit optional ``Load()`` values by default. .. _ast-compiler-flags: diff --git a/Doc/library/asyncio-stream.rst b/Doc/library/asyncio-stream.rst index c56166cabb9..90c90862ca1 100644 --- a/Doc/library/asyncio-stream.rst +++ b/Doc/library/asyncio-stream.rst @@ -171,13 +171,17 @@ and work with streams: .. function:: start_unix_server(client_connected_cb, path=None, \ *, limit=None, sock=None, backlog=100, ssl=None, \ ssl_handshake_timeout=None, \ - ssl_shutdown_timeout=None, start_serving=True) + ssl_shutdown_timeout=None, start_serving=True, cleanup_socket=True) :async: Start a Unix socket server. Similar to :func:`start_server` but works with Unix sockets. + If *cleanup_socket* is true then the Unix socket will automatically + be removed from the filesystem when the server is closed, unless the + socket has been replaced after the server has been created. + See also the documentation of :meth:`loop.create_unix_server`. .. note:: @@ -198,6 +202,9 @@ and work with streams: .. versionchanged:: 3.11 Added the *ssl_shutdown_timeout* parameter. + .. versionchanged:: 3.13 + Added the *cleanup_socket* parameter. + StreamReader ============ diff --git a/Doc/library/calendar.rst b/Doc/library/calendar.rst index 39090e36ed9..b292d828841 100644 --- a/Doc/library/calendar.rst +++ b/Doc/library/calendar.rst @@ -251,7 +251,7 @@ interpreted as prescribed by the ISO 8601 standard. Year 0 is 1 BC, year -1 is 3) specifies the number of months per row. *css* is the name for the cascading style sheet to be used. :const:`None` can be passed if no style sheet should be used. *encoding* specifies the encoding to be used for the - output (defaulting to the system default encoding). + output (defaulting to ``'utf-8'``). .. method:: formatmonthname(theyear, themonth, withyear=True) diff --git a/Doc/library/compileall.rst b/Doc/library/compileall.rst index c42288419c4..ebbbf857e71 100644 --- a/Doc/library/compileall.rst +++ b/Doc/library/compileall.rst @@ -56,11 +56,18 @@ compile Python sources. executed. .. option:: -s strip_prefix + + Remove the given prefix from paths recorded in the ``.pyc`` files. + Paths are made relative to the prefix. + + This option can be used with ``-p`` but not with ``-d``. + .. option:: -p prepend_prefix - Remove (``-s``) or append (``-p``) the given prefix of paths - recorded in the ``.pyc`` files. - Cannot be combined with ``-d``. + Prepend the given prefix to paths recorded in the ``.pyc`` files. + Use ``-p /`` to make the paths absolute. + + This option can be used with ``-s`` but not with ``-d``. .. option:: -x regex diff --git a/Doc/library/compression.zstd.rst b/Doc/library/compression.zstd.rst index 1e1802155a1..57ad8e3377f 100644 --- a/Doc/library/compression.zstd.rst +++ b/Doc/library/compression.zstd.rst @@ -247,6 +247,27 @@ Compressing and decompressing data in memory The *mode* argument is a :class:`ZstdCompressor` attribute, either :attr:`~.FLUSH_BLOCK`, or :attr:`~.FLUSH_FRAME`. + .. method:: set_pledged_input_size(size) + + Specify the amount of uncompressed data *size* that will be provided for + the next frame. *size* will be written into the frame header of the next + frame unless :attr:`CompressionParameter.content_size_flag` is ``False`` + or ``0``. A size of ``0`` means that the frame is empty. If *size* is + ``None``, the frame header will omit the frame size. Frames that include + the uncompressed data size require less memory to decompress, especially + at higher compression levels. + + If :attr:`last_mode` is not :attr:`FLUSH_FRAME`, a + :exc:`ValueError` is raised as the compressor is not at the start of + a frame. If the pledged size does not match the actual size of data + provided to :meth:`.compress`, future calls to :meth:`!compress` or + :meth:`flush` may raise :exc:`ZstdError` and the last chunk of data may + be lost. + + After :meth:`flush` or :meth:`.compress` are called with mode + :attr:`FLUSH_FRAME`, the next frame will not include the frame size into + the header unless :meth:`!set_pledged_input_size` is called again. + .. attribute:: CONTINUE Collect more data for compression, which may or may not generate output @@ -266,6 +287,13 @@ Compressing and decompressing data in memory :meth:`~.compress` will be written into a new frame and *cannot* reference past data. + .. attribute:: last_mode + + The last mode passed to either :meth:`~.compress` or :meth:`~.flush`. + The value can be one of :attr:`~.CONTINUE`, :attr:`~.FLUSH_BLOCK`, or + :attr:`~.FLUSH_FRAME`. The initial value is :attr:`~.FLUSH_FRAME`, + signifying that the compressor is at the start of a new frame. + .. class:: ZstdDecompressor(zstd_dict=None, options=None) @@ -615,6 +643,29 @@ Advanced parameter control A value of zero causes the value to be selected automatically. + .. attribute:: content_size_flag + + Write the size of the data to be compressed into the Zstandard frame + header when known prior to compressing. + + This flag only takes effect under the following scenarios: + + * Calling :func:`compress` for one-shot compression + * Providing all of the data to be compressed in the frame in a single + :meth:`ZstdCompressor.compress` call, with the + :attr:`ZstdCompressor.FLUSH_FRAME` mode. + * Calling :meth:`ZstdCompressor.set_pledged_input_size` with the exact + amount of data that will be provided to the compressor prior to any + calls to :meth:`ZstdCompressor.compress` for the current frame. + :meth:`!ZstdCompressor.set_pledged_input_size` must be called for each + new frame. + + All other compression calls may not write the size information into the + frame header. + + ``True`` or ``1`` enable the content size flag while ``False`` or ``0`` + disable it. + .. attribute:: checksum_flag A four-byte checksum using XXHash64 of the uncompressed content is diff --git a/Doc/library/concurrency.rst b/Doc/library/concurrency.rst index 5be1a1106b0..18f9443cbfe 100644 --- a/Doc/library/concurrency.rst +++ b/Doc/library/concurrency.rst @@ -18,6 +18,7 @@ multitasking). Here's an overview: multiprocessing.shared_memory.rst concurrent.rst concurrent.futures.rst + concurrent.interpreters.rst subprocess.rst sched.rst queue.rst diff --git a/Doc/library/concurrent.interpreters.rst b/Doc/library/concurrent.interpreters.rst new file mode 100644 index 00000000000..8860418e87a --- /dev/null +++ b/Doc/library/concurrent.interpreters.rst @@ -0,0 +1,198 @@ +:mod:`!concurrent.interpreters` --- Multiple interpreters in the same process +============================================================================= + +.. module:: concurrent.interpreters + :synopsis: Multiple interpreters in the same process + +.. moduleauthor:: Eric Snow <ericsnowcurrently@gmail.com> +.. sectionauthor:: Eric Snow <ericsnowcurrently@gmail.com> + +.. versionadded:: 3.14 + +**Source code:** :source:`Lib/concurrent/interpreters.py` + +-------------- + + +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. + +.. seealso:: + + :ref:`isolating-extensions-howto` + how to update an extension module to support multiple interpreters + + :pep:`554` + + :pep:`734` + + :pep:`684` + +.. XXX Why do we disallow multiple interpreters on WASM? + +.. include:: ../includes/wasm-notavail.rst + + +Key details +----------- + +Before we dive into examples, there are a small number of details +to keep in mind about using multiple interpreters: + +* isolated, 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. + + +Reference +--------- + +This module defines the following functions: + +.. function:: list_all() + + Return a :class:`list` of :class:`Interpreter` objects, + one for each existing interpreter. + +.. function:: get_current() + + Return an :class:`Interpreter` object for the currently running + interpreter. + +.. function:: get_main() + + Return an :class:`Interpreter` object for the main interpreter. + +.. function:: create() + + Initialize a new (idle) Python interpreter + and return a :class:`Interpreter` object for it. + + +Interpreter objects +^^^^^^^^^^^^^^^^^^^ + +.. class:: Interpreter(id) + + A single interpreter in the current process. + + Generally, :class:`Interpreter` shouldn't be called directly. + Instead, use :func:`create` or one of the other module functions. + + .. attribute:: id + + (read-only) + + The interpreter's ID. + + .. attribute:: whence + + (read-only) + + A string describing where the interpreter came from. + + .. method:: is_running() + + Return ``True`` if the interpreter is currently executing code + in its :mod:`!__main__` module and ``False`` otherwise. + + .. method:: close() + + Finalize and destroy the interpreter. + + .. method:: prepare_main(ns=None, **kwargs) + + Bind "shareable" objects in the interpreter's + :mod:`!__main__` module. + + .. method:: exec(code, /, dedent=True) + + Run the given source code in the interpreter (in the current thread). + + .. method:: call(callable, /, *args, **kwargs) + + Return the result of calling running the given function in the + interpreter (in the current thread). + + .. method:: call_in_thread(callable, /, *args, **kwargs) + + Run the given function in the interpreter (in a new thread). + +Exceptions +^^^^^^^^^^ + +.. exception:: InterpreterError + + This exception, a subclass of :exc:`Exception`, is raised when + an interpreter-related error happens. + +.. exception:: InterpreterNotFoundError + + This exception, a subclass of :exc:`InterpreterError`, is raised when + the targeted interpreter no longer exists. + +.. exception:: ExecutionFailed + + This exception, a subclass of :exc:`InterpreterError`, is raised when + the running code raised an uncaught exception. + + .. attribute:: excinfo + + A basic snapshot of the exception raised in the other interpreter. + +.. XXX Document the excinfoattrs? + +.. exception:: NotShareableError + + This exception, a subclass of :exc:`TypeError`, is raised when + an object cannot be sent to another interpreter. + + +.. XXX Add functions for communicating between interpreters. + + +Basic usage +----------- + +Creating an interpreter and running code in it:: + + from concurrent import interpreters + + interp = interpreters.create() + + # Run in the current OS thread. + + interp.exec('print("spam!")') + + interp.exec("""if True: + print('spam!') + """) + + from textwrap import dedent + interp.exec(dedent(""" + print('spam!') + """)) + + def run(): + print('spam!') + + interp.call(run) + + # Run in new OS thread. + + t = interp.call_in_thread(run) + t.join() + + +.. XXX Explain about object "sharing". diff --git a/Doc/library/concurrent.rst b/Doc/library/concurrent.rst index 8caea78bbb5..748c72c733b 100644 --- a/Doc/library/concurrent.rst +++ b/Doc/library/concurrent.rst @@ -1,6 +1,7 @@ The :mod:`!concurrent` package ============================== -Currently, there is only one module in this package: +This package contains the following modules: * :mod:`concurrent.futures` -- Launching parallel tasks +* :mod:`concurrent.interpreters` -- Multiple interpreters in the same process diff --git a/Doc/library/copy.rst b/Doc/library/copy.rst index 95b41f988a0..210ad718800 100644 --- a/Doc/library/copy.rst +++ b/Doc/library/copy.rst @@ -122,6 +122,8 @@ and only supports named tuples created by :func:`~collections.namedtuple`, This method should create a new object of the same type, replacing fields with values from *changes*. + .. versionadded:: 3.13 + .. seealso:: diff --git a/Doc/library/csv.rst b/Doc/library/csv.rst index 533cdf13974..2e513bff651 100644 --- a/Doc/library/csv.rst +++ b/Doc/library/csv.rst @@ -70,7 +70,7 @@ The :mod:`csv` module defines the following functions: section :ref:`csv-fmt-params`. Each row read from the csv file is returned as a list of strings. No - automatic data type conversion is performed unless the ``QUOTE_NONNUMERIC`` format + automatic data type conversion is performed unless the :data:`QUOTE_NONNUMERIC` format option is specified (in which case unquoted fields are transformed into floats). A short usage example:: @@ -331,8 +331,14 @@ The :mod:`csv` module defines the following constants: Instructs :class:`writer` objects to quote all non-numeric fields. - Instructs :class:`reader` objects to convert all non-quoted fields to type *float*. + Instructs :class:`reader` objects to convert all non-quoted fields to type :class:`float`. + .. note:: + Some numeric types, such as :class:`bool`, :class:`~fractions.Fraction`, + or :class:`~enum.IntEnum`, have a string representation that cannot be + converted to :class:`float`. + They cannot be read in the :data:`QUOTE_NONNUMERIC` and + :data:`QUOTE_STRINGS` modes. .. data:: QUOTE_NONE @@ -603,7 +609,7 @@ A slightly more advanced use of the reader --- catching and reporting errors:: for row in reader: print(row) except csv.Error as e: - sys.exit('file {}, line {}: {}'.format(filename, reader.line_num, e)) + sys.exit(f'file {filename}, line {reader.line_num}: {e}') And while the module doesn't directly support parsing strings, it can easily be done:: diff --git a/Doc/library/ctypes.rst b/Doc/library/ctypes.rst index 5b733d5321e..e00fe9c8145 100644 --- a/Doc/library/ctypes.rst +++ b/Doc/library/ctypes.rst @@ -714,10 +714,16 @@ item in the :attr:`~Structure._fields_` tuples:: ... ("second_16", c_int, 16)] ... >>> print(Int.first_16) - <Field type=c_long, ofs=0:0, bits=16> + <ctypes.CField 'first_16' type=c_int, ofs=0, bit_size=16, bit_offset=0> >>> print(Int.second_16) - <Field type=c_long, ofs=0:16, bits=16> - >>> + <ctypes.CField 'second_16' type=c_int, ofs=0, bit_size=16, bit_offset=16> + +It is important to note that bit field allocation and layout in memory are not +defined as a C standard; their implementation is compiler-specific. +By default, Python will attempt to match the behavior of a "native" compiler +for the current platform. +See the :attr:`~Structure._layout_` attribute for details on the default +behavior and how to change it. .. _ctypes-arrays: @@ -876,7 +882,7 @@ invalid non-\ ``NULL`` pointers would crash Python):: Thread safety without the GIL ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -In Python 3.13, the :term:`GIL` may be disabled on :term:`experimental free threaded <free threading>` builds. +From Python 3.13 onward, the :term:`GIL` can be disabled on :term:`free threaded <free threading>` builds. In ctypes, reads and writes to a single object concurrently is safe, but not across multiple objects: .. code-block:: pycon @@ -2031,35 +2037,55 @@ Utility functions pointer. -.. function:: create_string_buffer(init_or_size, size=None) +.. function:: create_string_buffer(init, size=None) + create_string_buffer(size) This function creates a mutable character buffer. The returned object is a ctypes array of :class:`c_char`. - *init_or_size* must be an integer which specifies the size of the array, or a - bytes object which will be used to initialize the array items. + If *size* is given (and not ``None``), it must be an :class:`int`. + It specifies the size of the returned array. + + If the *init* argument is given, it must be :class:`bytes`. It is used + to initialize the array items. Bytes not initialized this way are + set to zero (NUL). + + If *size* is not given (or if it is ``None``), the buffer is made one element + larger than *init*, effectively adding a NUL terminator. + + If both arguments are given, *size* must not be less than ``len(init)``. - If a bytes object is specified as first argument, the buffer is made one item - larger than its length so that the last element in the array is a NUL - termination character. An integer can be passed as second argument which allows - specifying the size of the array if the length of the bytes should not be used. + .. warning:: + + If *size* is equal to ``len(init)``, a NUL terminator is + not added. Do not treat such a buffer as a C string. + + For example:: + + >>> bytes(create_string_buffer(2)) + b'\x00\x00' + >>> bytes(create_string_buffer(b'ab')) + b'ab\x00' + >>> bytes(create_string_buffer(b'ab', 2)) + b'ab' + >>> bytes(create_string_buffer(b'ab', 4)) + b'ab\x00\x00' + >>> bytes(create_string_buffer(b'abcdef', 2)) + Traceback (most recent call last): + ... + ValueError: byte string too long .. audit-event:: ctypes.create_string_buffer init,size ctypes.create_string_buffer -.. function:: create_unicode_buffer(init_or_size, size=None) +.. function:: create_unicode_buffer(init, size=None) + create_unicode_buffer(size) This function creates a mutable unicode character buffer. The returned object is a ctypes array of :class:`c_wchar`. - *init_or_size* must be an integer which specifies the size of the array, or a - string which will be used to initialize the array items. - - If a string is specified as first argument, the buffer is made one item - larger than the length of the string so that the last element in the array is a - NUL termination character. An integer can be passed as second argument which - allows specifying the size of the array if the length of the string should not - be used. + The function takes the same arguments as :func:`~create_string_buffer` except + *init* must be a string and *size* counts :class:`c_wchar`. .. audit-event:: ctypes.create_unicode_buffer init,size ctypes.create_unicode_buffer diff --git a/Doc/library/dataclasses.rst b/Doc/library/dataclasses.rst index f18c7cc9c02..299c8aa399c 100644 --- a/Doc/library/dataclasses.rst +++ b/Doc/library/dataclasses.rst @@ -121,8 +121,11 @@ Module contents :meth:`!__le__`, :meth:`!__gt__`, or :meth:`!__ge__`, then :exc:`TypeError` is raised. - - *unsafe_hash*: If ``False`` (the default), a :meth:`~object.__hash__` method - is generated according to how *eq* and *frozen* are set. + - *unsafe_hash*: If true, force ``dataclasses`` to create a + :meth:`~object.__hash__` method, even though it may not be safe to do so. + Otherwise, generate a :meth:`~object.__hash__` method according to how + *eq* and *frozen* are set. + The default value is ``False``. :meth:`!__hash__` is used by built-in :meth:`hash`, and when objects are added to hashed collections such as dictionaries and sets. Having a diff --git a/Doc/library/dbm.rst b/Doc/library/dbm.rst index 36221c026d6..39e287b1521 100644 --- a/Doc/library/dbm.rst +++ b/Doc/library/dbm.rst @@ -15,10 +15,16 @@ * :mod:`dbm.ndbm` If none of these modules are installed, the -slow-but-simple implementation in module :mod:`dbm.dumb` will be used. There +slow-but-simple implementation in module :mod:`dbm.dumb` will be used. There is a `third party interface <https://www.jcea.es/programacion/pybsddb.htm>`_ to the Oracle Berkeley DB. +.. note:: + None of the underlying modules will automatically shrink the disk space used by + the database file. However, :mod:`dbm.sqlite3`, :mod:`dbm.gnu` and :mod:`dbm.dumb` + provide a :meth:`!reorganize` method that can be used for this purpose. + + .. exception:: error A tuple containing the exceptions that can be raised by each of the supported @@ -186,6 +192,17 @@ or any other SQLite browser, including the SQLite CLI. The Unix file access mode of the file (default: octal ``0o666``), used only when the database has to be created. + .. method:: sqlite3.reorganize() + + If you have carried out a lot of deletions and would like to shrink the space + used on disk, this method will reorganize the database; otherwise, deleted file + space will be kept and reused as new (key, value) pairs are added. + + .. note:: + While reorganizing, as much as two times the size of the original database is required + in free disk space. However, be aware that this factor changes for each :mod:`dbm` submodule. + + .. versionadded:: next :mod:`dbm.gnu` --- GNU database manager --------------------------------------- @@ -237,6 +254,9 @@ functionality like crash tolerance. * ``'s'``: Synchronized mode. Changes to the database will be written immediately to the file. * ``'u'``: Do not lock database. + * ``'m'``: Do not use :manpage:`mmap(2)`. + This may harm performance, but improve crash tolerance. + .. versionadded:: next Not all flags are valid for all versions of GDBM. See the :data:`open_flags` member for a list of supported flag characters. @@ -284,6 +304,10 @@ functionality like crash tolerance. reorganization; otherwise, deleted file space will be kept and reused as new (key, value) pairs are added. + .. note:: + While reorganizing, as much as one time the size of the original database is required + in free disk space. However, be aware that this factor changes for each :mod:`dbm` submodule. + .. method:: gdbm.sync() When the database has been opened in fast mode, this method forces any @@ -438,6 +462,11 @@ The :mod:`!dbm.dumb` module defines the following: with a sufficiently large/complex entry due to stack depth limitations in Python's AST compiler. + .. warning:: + :mod:`dbm.dumb` does not support concurrent read/write access. (Multiple + simultaneous read accesses are safe.) When a program has the database open + for writing, no other program should have it open for reading or writing. + .. versionchanged:: 3.5 :func:`~dbm.dumb.open` always creates a new database when *flag* is ``'n'``. @@ -460,3 +489,15 @@ The :mod:`!dbm.dumb` module defines the following: .. method:: dumbdbm.close() Close the database. + + .. method:: dumbdbm.reorganize() + + If you have carried out a lot of deletions and would like to shrink the space + used on disk, this method will reorganize the database; otherwise, deleted file + space will not be reused. + + .. note:: + While reorganizing, no additional free disk space is required. However, be aware + that this factor changes for each :mod:`dbm` submodule. + + .. versionadded:: next diff --git a/Doc/library/doctest.rst b/Doc/library/doctest.rst index b86fef9fd6f..fb43cf918b8 100644 --- a/Doc/library/doctest.rst +++ b/Doc/library/doctest.rst @@ -174,7 +174,7 @@ with assorted summaries at the end. You can force verbose mode by passing ``verbose=True`` to :func:`testmod`, or prohibit it by passing ``verbose=False``. In either of those cases, -``sys.argv`` is not examined by :func:`testmod` (so passing ``-v`` or not +:data:`sys.argv` is not examined by :func:`testmod` (so passing ``-v`` or not has no effect). There is also a command line shortcut for running :func:`testmod`, see section @@ -231,7 +231,7 @@ documentation:: As with :func:`testmod`, :func:`testfile` won't display anything unless an example fails. If an example does fail, then the failing example(s) and the cause(s) of the failure(s) are printed to stdout, using the same format as -:func:`testmod`. +:func:`!testmod`. By default, :func:`testfile` looks for files in the calling module's directory. See section :ref:`doctest-basic-api` for a description of the optional arguments @@ -311,6 +311,9 @@ Which Docstrings Are Examined? The module docstring, and all function, class and method docstrings are searched. Objects imported into the module are not searched. +.. attribute:: module.__test__ + :no-typesetting: + In addition, there are cases when you want tests to be part of a module but not part of the help text, which requires that the tests not be included in the docstring. Doctest looks for a module-level variable called ``__test__`` and uses it to locate other @@ -533,7 +536,7 @@ Some details you should read once, but won't need to remember: * The interactive shell omits the traceback header line for some :exc:`SyntaxError`\ s. But doctest uses the traceback header line to distinguish exceptions from non-exceptions. So in the rare case where you need - to test a :exc:`SyntaxError` that omits the traceback header, you will need to + to test a :exc:`!SyntaxError` that omits the traceback header, you will need to manually add the traceback header line to your test example. .. index:: single: ^ (caret); marker @@ -860,15 +863,15 @@ The :const:`ELLIPSIS` directive gives a nice approach for the last example: <C object at 0x...> Floating-point numbers are also subject to small output variations across -platforms, because Python defers to the platform C library for float formatting, -and C libraries vary widely in quality here. :: +platforms, because Python defers to the platform C library for some +floating-point calculations, and C libraries vary widely in quality here. :: - >>> 1./7 # risky - 0.14285714285714285 - >>> print(1./7) # safer - 0.142857142857 - >>> print(round(1./7, 6)) # much safer - 0.142857 + >>> 1000**0.1 # risky + 1.9952623149688797 + >>> round(1000**0.1, 9) # safer + 1.995262315 + >>> print(f'{1000**0.1:.4f}') # much safer + 1.9953 Numbers of the form ``I/2.**J`` are safe across all platforms, and I often contrive doctest examples to produce numbers of that form:: @@ -938,13 +941,13 @@ and :ref:`doctest-simple-testfile`. Optional argument *verbose* prints lots of stuff if true, and prints only failures if false; by default, or if ``None``, it's true if and only if ``'-v'`` - is in ``sys.argv``. + is in :data:`sys.argv`. Optional argument *report* prints a summary at the end when true, else prints nothing at the end. In verbose mode, the summary is detailed, else the summary is very brief (in fact, empty if all tests passed). - Optional argument *optionflags* (default value 0) takes the + Optional argument *optionflags* (default value ``0``) takes the :ref:`bitwise OR <bitwise>` of option flags. See section :ref:`doctest-options`. @@ -1043,12 +1046,15 @@ from text files and modules with doctests: Convert doctest tests from one or more text files to a :class:`unittest.TestSuite`. - The returned :class:`unittest.TestSuite` is to be run by the unittest framework - and runs the interactive examples in each file. If an example in any file - fails, then the synthesized unit test fails, and a :exc:`failureException` - exception is raised showing the name of the file containing the test and a - (sometimes approximate) line number. If all the examples in a file are - skipped, then the synthesized unit test is also marked as skipped. + The returned :class:`unittest.TestSuite` is to be run by the unittest + framework and runs the interactive examples in each file. + Each file is run as a separate unit test, and each example in a file + is run as a :ref:`subtest <subtests>`. + If any example in a file fails, then the synthesized unit test fails. + The traceback for failure or error contains the name of the file + containing the test and a (sometimes approximate) line number. + If all the examples in a file are skipped, then the synthesized unit + test is also marked as skipped. Pass one or more paths (as strings) to text files to be examined. @@ -1078,13 +1084,14 @@ from text files and modules with doctests: Optional argument *setUp* specifies a set-up function for the test suite. This is called before running the tests in each file. The *setUp* function - will be passed a :class:`DocTest` object. The setUp function can access the - test globals as the *globs* attribute of the test passed. + will be passed a :class:`DocTest` object. The *setUp* function can access the + test globals as the :attr:`~DocTest.globs` attribute of the test passed. Optional argument *tearDown* specifies a tear-down function for the test suite. This is called after running the tests in each file. The *tearDown* - function will be passed a :class:`DocTest` object. The setUp function can - access the test globals as the *globs* attribute of the test passed. + function will be passed a :class:`DocTest` object. The *tearDown* function can + access the test globals as the :attr:`~DocTest.globs` attribute of the test + passed. Optional argument *globs* is a dictionary containing the initial global variables for the tests. A new copy of this dictionary is created for each @@ -1105,16 +1112,22 @@ from text files and modules with doctests: The global ``__file__`` is added to the globals provided to doctests loaded from a text file using :func:`DocFileSuite`. + .. versionchanged:: next + Run each example as a :ref:`subtest <subtests>`. + .. function:: DocTestSuite(module=None, globs=None, extraglobs=None, test_finder=None, setUp=None, tearDown=None, optionflags=0, checker=None) Convert doctest tests for a module to a :class:`unittest.TestSuite`. - The returned :class:`unittest.TestSuite` is to be run by the unittest framework - and runs each doctest in the module. If any of the doctests fail, then the - synthesized unit test fails, and a :exc:`failureException` exception is raised - showing the name of the file containing the test and a (sometimes approximate) - line number. If all the examples in a docstring are skipped, then the + The returned :class:`unittest.TestSuite` is to be run by the unittest + framework and runs each doctest in the module. + Each docstring is run as a separate unit test, and each example in + a docstring is run as a :ref:`subtest <subtests>`. + If any of the doctests fail, then the synthesized unit test fails. + The traceback for failure or error contains the name of the file + containing the test and a (sometimes approximate) line number. + If all the examples in a docstring are skipped, then the synthesized unit test is also marked as skipped. Optional argument *module* provides the module to be tested. It can be a module @@ -1123,7 +1136,7 @@ from text files and modules with doctests: Optional argument *globs* is a dictionary containing the initial global variables for the tests. A new copy of this dictionary is created for each - test. By default, *globs* is a new empty dictionary. + test. By default, *globs* is the module's :attr:`~module.__dict__`. Optional argument *extraglobs* specifies an extra set of global variables, which is merged into *globs*. By default, no extra globals are used. @@ -1132,7 +1145,7 @@ from text files and modules with doctests: drop-in replacement) that is used to extract doctests from the module. Optional arguments *setUp*, *tearDown*, and *optionflags* are the same as for - function :func:`DocFileSuite` above. + function :func:`DocFileSuite` above, but they are called for each docstring. This function uses the same search technique as :func:`testmod`. @@ -1140,11 +1153,8 @@ from text files and modules with doctests: :func:`DocTestSuite` returns an empty :class:`unittest.TestSuite` if *module* contains no docstrings instead of raising :exc:`ValueError`. -.. exception:: failureException - - When doctests which have been converted to unit tests by :func:`DocFileSuite` - or :func:`DocTestSuite` fail, this exception is raised showing the name of - the file containing the test and a (sometimes approximate) line number. + .. versionchanged:: next + Run each example as a :ref:`subtest <subtests>`. Under the covers, :func:`DocTestSuite` creates a :class:`unittest.TestSuite` out of :class:`!doctest.DocTestCase` instances, and :class:`!DocTestCase` is a @@ -1158,15 +1168,15 @@ of :class:`!DocTestCase`. So both ways of creating a :class:`unittest.TestSuite` run instances of :class:`!DocTestCase`. This is important for a subtle reason: when you run -:mod:`doctest` functions yourself, you can control the :mod:`doctest` options in -use directly, by passing option flags to :mod:`doctest` functions. However, if -you're writing a :mod:`unittest` framework, :mod:`unittest` ultimately controls +:mod:`doctest` functions yourself, you can control the :mod:`!doctest` options in +use directly, by passing option flags to :mod:`!doctest` functions. However, if +you're writing a :mod:`unittest` framework, :mod:`!unittest` ultimately controls when and how tests get run. The framework author typically wants to control -:mod:`doctest` reporting options (perhaps, e.g., specified by command line -options), but there's no way to pass options through :mod:`unittest` to -:mod:`doctest` test runners. +:mod:`!doctest` reporting options (perhaps, e.g., specified by command line +options), but there's no way to pass options through :mod:`!unittest` to +:mod:`!doctest` test runners. -For this reason, :mod:`doctest` also supports a notion of :mod:`doctest` +For this reason, :mod:`doctest` also supports a notion of :mod:`!doctest` reporting flags specific to :mod:`unittest` support, via this function: @@ -1181,12 +1191,12 @@ reporting flags specific to :mod:`unittest` support, via this function: :mod:`unittest`: the :meth:`!runTest` method of :class:`!DocTestCase` looks at the option flags specified for the test case when the :class:`!DocTestCase` instance was constructed. If no reporting flags were specified (which is the - typical and expected case), :mod:`!doctest`'s :mod:`unittest` reporting flags are + typical and expected case), :mod:`!doctest`'s :mod:`!unittest` reporting flags are :ref:`bitwise ORed <bitwise>` into the option flags, and the option flags so augmented are passed to the :class:`DocTestRunner` instance created to run the doctest. If any reporting flags were specified when the :class:`!DocTestCase` instance was constructed, :mod:`!doctest`'s - :mod:`unittest` reporting flags are ignored. + :mod:`!unittest` reporting flags are ignored. The value of the :mod:`unittest` reporting flags in effect before the function was called is returned by the function. @@ -1279,7 +1289,7 @@ DocTest Objects .. attribute:: filename The name of the file that this :class:`DocTest` was extracted from; or - ``None`` if the filename is unknown, or if the :class:`DocTest` was not + ``None`` if the filename is unknown, or if the :class:`!DocTest` was not extracted from a file. @@ -1419,10 +1429,10 @@ DocTestFinder objects The globals for each :class:`DocTest` is formed by combining *globs* and *extraglobs* (bindings in *extraglobs* override bindings in *globs*). A new - shallow copy of the globals dictionary is created for each :class:`DocTest`. - If *globs* is not specified, then it defaults to the module's *__dict__*, if - specified, or ``{}`` otherwise. If *extraglobs* is not specified, then it - defaults to ``{}``. + shallow copy of the globals dictionary is created for each :class:`!DocTest`. + If *globs* is not specified, then it defaults to the module's + :attr:`~module.__dict__`, if specified, or ``{}`` otherwise. + If *extraglobs* is not specified, then it defaults to ``{}``. .. _doctest-doctestparser: @@ -1446,7 +1456,7 @@ DocTestParser objects :class:`DocTest` object. *globs*, *name*, *filename*, and *lineno* are attributes for the new - :class:`DocTest` object. See the documentation for :class:`DocTest` for more + :class:`!DocTest` object. See the documentation for :class:`DocTest` for more information. @@ -1461,7 +1471,7 @@ DocTestParser objects Divide the given string into examples and intervening text, and return them as a list of alternating :class:`Example`\ s and strings. Line numbers for the - :class:`Example`\ s are 0-based. The optional argument *name* is a name + :class:`!Example`\ s are 0-based. The optional argument *name* is a name identifying this string, and is only used for error messages. @@ -1501,14 +1511,14 @@ DocTestRunner objects :class:`OutputChecker`. This comparison may be customized with a number of option flags; see section :ref:`doctest-options` for more information. If the option flags are insufficient, then the comparison may also be customized by - passing a subclass of :class:`OutputChecker` to the constructor. + passing a subclass of :class:`!OutputChecker` to the constructor. The test runner's display output can be controlled in two ways. First, an output function can be passed to :meth:`run`; this function will be called with strings that should be displayed. It defaults to ``sys.stdout.write``. If capturing the output is not sufficient, then the display output can be also customized by subclassing DocTestRunner, and overriding the methods - :meth:`report_start`, :meth:`report_success`, + :meth:`report_skip`, :meth:`report_start`, :meth:`report_success`, :meth:`report_unexpected_exception`, and :meth:`report_failure`. The optional keyword argument *checker* specifies the :class:`OutputChecker` @@ -1533,6 +1543,19 @@ DocTestRunner objects :class:`DocTestRunner` defines the following methods: + .. method:: report_skip(out, test, example) + + Report that the given example was skipped. This method is provided to + allow subclasses of :class:`DocTestRunner` to customize their output; it + should not be called directly. + + *example* is the example about to be processed. *test* is the test + containing *example*. *out* is the output function that was passed to + :meth:`DocTestRunner.run`. + + .. versionadded:: next + + .. method:: report_start(out, test, example) Report that the test runner is about to process the given example. This method @@ -1540,7 +1563,7 @@ DocTestRunner objects output; it should not be called directly. *example* is the example about to be processed. *test* is the test - *containing example*. *out* is the output function that was passed to + containing *example*. *out* is the output function that was passed to :meth:`DocTestRunner.run`. @@ -1940,7 +1963,7 @@ several options for organizing tests: containing test cases for the named topics. These functions can be included in the same file as the module, or separated out into a separate test file. -* Define a ``__test__`` dictionary mapping from regression test topics to +* Define a :attr:`~module.__test__` dictionary mapping from regression test topics to docstrings containing test cases. When you have placed your tests in a module, the module can itself be the test diff --git a/Doc/library/email.header.rst b/Doc/library/email.header.rst index 219fad0d2f6..c3392a62b8e 100644 --- a/Doc/library/email.header.rst +++ b/Doc/library/email.header.rst @@ -178,16 +178,36 @@ The :mod:`email.header` module also provides the following convenient functions. Decode a message header value without converting the character set. The header value is in *header*. - This function returns a list of ``(decoded_string, charset)`` pairs containing - each of the decoded parts of the header. *charset* is ``None`` for non-encoded - parts of the header, otherwise a lower case string containing the name of the - character set specified in the encoded string. + For historical reasons, this function may return either: - Here's an example:: + 1. A list of pairs containing each of the decoded parts of the header, + ``(decoded_bytes, charset)``, where *decoded_bytes* is always an instance of + :class:`bytes`, and *charset* is either: + + - A lower case string containing the name of the character set specified. + + - ``None`` for non-encoded parts of the header. + + 2. A list of length 1 containing a pair ``(string, None)``, where + *string* is always an instance of :class:`str`. + + An :exc:`email.errors.HeaderParseError` may be raised when certain decoding + errors occur (e.g. a base64 decoding exception). + + Here are examples: >>> from email.header import decode_header >>> decode_header('=?iso-8859-1?q?p=F6stal?=') [(b'p\xf6stal', 'iso-8859-1')] + >>> decode_header('unencoded_string') + [('unencoded_string', None)] + >>> decode_header('bar =?utf-8?B?ZsOzbw==?=') + [(b'bar ', None), (b'f\xc3\xb3o', 'utf-8')] + + .. note:: + + This function exists for for backwards compatibility only. For + new code, we recommend using :class:`email.headerregistry.HeaderRegistry`. .. function:: make_header(decoded_seq, maxlinelen=None, header_name=None, continuation_ws=' ') @@ -203,3 +223,7 @@ The :mod:`email.header` module also provides the following convenient functions. :class:`Header` instance. Optional *maxlinelen*, *header_name*, and *continuation_ws* are as in the :class:`Header` constructor. + .. note:: + + This function exists for for backwards compatibility only, and is + not recommended for use in new code. diff --git a/Doc/library/hashlib.rst b/Doc/library/hashlib.rst index 4818a4944a5..8bba6700930 100644 --- a/Doc/library/hashlib.rst +++ b/Doc/library/hashlib.rst @@ -94,6 +94,13 @@ accessible by name via :func:`new`. See :data:`algorithms_available`. OpenSSL does not provide we fall back to a verified implementation from the `HACL\* project`_. +.. deprecated-removed:: 3.15 3.19 + The undocumented ``string`` keyword parameter in :func:`!_hashlib.new` + and hash-named constructors such as :func:`!_md5.md5` is deprecated. + Prefer passing the initial data as a positional argument for maximum + backwards compatibility. + + Usage ----- diff --git a/Doc/library/logging.config.rst b/Doc/library/logging.config.rst index 0e9dc33ae21..f8c71005a53 100644 --- a/Doc/library/logging.config.rst +++ b/Doc/library/logging.config.rst @@ -548,7 +548,7 @@ mnemonic that the corresponding value is a callable. The ``filters`` member of ``handlers`` and ``loggers`` can take filter instances in addition to ids. -You can also specify a special key ``'.'`` whose value is a dictionary is a +You can also specify a special key ``'.'`` whose value is a mapping of attribute names to values. If found, the specified attributes will be set on the user-defined object before it is returned. Thus, with the following configuration:: diff --git a/Doc/library/logging.handlers.rst b/Doc/library/logging.handlers.rst index 63ef533e82c..8f3aa1dfdd0 100644 --- a/Doc/library/logging.handlers.rst +++ b/Doc/library/logging.handlers.rst @@ -352,6 +352,10 @@ module, supports rotation of disk log files. Outputs the record to the file, catering for rollover as described previously. + .. method:: shouldRollover(record) + + See if the supplied record would cause the file to exceed the configured size limit. + .. _timed-rotating-file-handler: TimedRotatingFileHandler @@ -459,7 +463,11 @@ timed intervals. .. method:: getFilesToDelete() Returns a list of filenames which should be deleted as part of rollover. These - are the absolute paths of the oldest backup log files written by the handler. + + .. method:: shouldRollover(record) + + See if enough time has passed for a rollover to occur and if it has, compute + the next rollover time. .. _socket-handler: diff --git a/Doc/library/math.rst b/Doc/library/math.rst index 394a462b946..ecb1d4102ca 100644 --- a/Doc/library/math.rst +++ b/Doc/library/math.rst @@ -10,8 +10,8 @@ -------------- -This module provides access to the mathematical functions defined by the C -standard. +This module provides access to common mathematical functions and constants, +including those defined by the C standard. These functions cannot be used with complex numbers; use the functions of the same name from the :mod:`cmath` module if you require support for complex @@ -53,6 +53,8 @@ noted otherwise, all return values are floats. :func:`frexp(x) <frexp>` Mantissa and exponent of *x* :func:`isclose(a, b, rel_tol, abs_tol) <isclose>` Check if the values *a* and *b* are close to each other :func:`isfinite(x) <isfinite>` Check if *x* is neither an infinity nor a NaN +:func:`isnormal(x) <isnormal>` Check if *x* is a normal number +:func:`issubnormal(x) <issubnormal>` Check if *x* is a subnormal number :func:`isinf(x) <isinf>` Check if *x* is a positive or negative infinity :func:`isnan(x) <isnan>` Check if *x* is a NaN (not a number) :func:`ldexp(x, i) <ldexp>` ``x * (2**i)``, inverse of function :func:`frexp` @@ -373,6 +375,24 @@ Floating point manipulation functions .. versionadded:: 3.2 +.. function:: isnormal(x) + + Return ``True`` if *x* is a normal number, that is a finite + nonzero number that is not a subnormal (see :func:`issubnormal`). + Return ``False`` otherwise. + + .. versionadded:: next + + +.. function:: issubnormal(x) + + Return ``True`` if *x* is a subnormal number, that is a finite + nonzero number with a magnitude smaller than :data:`sys.float_info.min`. + Return ``False`` otherwise. + + .. versionadded:: next + + .. function:: isinf(x) Return ``True`` if *x* is a positive or negative infinity, and diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst index 80e33c4a1df..fc3c1134f97 100644 --- a/Doc/library/multiprocessing.rst +++ b/Doc/library/multiprocessing.rst @@ -1081,7 +1081,7 @@ Miscellaneous .. function:: freeze_support() Add support for when a program which uses :mod:`multiprocessing` has been - frozen to produce a Windows executable. (Has been tested with **py2exe**, + frozen to produce an executable. (Has been tested with **py2exe**, **PyInstaller** and **cx_Freeze**.) One needs to call this function straight after the ``if __name__ == @@ -1099,10 +1099,10 @@ Miscellaneous If the ``freeze_support()`` line is omitted then trying to run the frozen executable will raise :exc:`RuntimeError`. - Calling ``freeze_support()`` has no effect when invoked on any operating - system other than Windows. In addition, if the module is being run - normally by the Python interpreter on Windows (the program has not been - frozen), then ``freeze_support()`` has no effect. + Calling ``freeze_support()`` has no effect when the start method is not + *spawn*. In addition, if the module is being run normally by the Python + interpreter (the program has not been frozen), then ``freeze_support()`` + has no effect. .. function:: get_all_start_methods() diff --git a/Doc/library/os.path.rst b/Doc/library/os.path.rst index ecbbc1d7605..f72aee19d8f 100644 --- a/Doc/library/os.path.rst +++ b/Doc/library/os.path.rst @@ -408,9 +408,26 @@ the :mod:`glob` module.) system). On Windows, this function will also resolve MS-DOS (also called 8.3) style names such as ``C:\\PROGRA~1`` to ``C:\\Program Files``. - If a path doesn't exist or a symlink loop is encountered, and *strict* is - ``True``, :exc:`OSError` is raised. If *strict* is ``False`` these errors - are ignored, and so the result might be missing or otherwise inaccessible. + By default, the path is evaluated up to the first component that does not + exist, is a symlink loop, or whose evaluation raises :exc:`OSError`. + All such components are appended unchanged to the existing part of the path. + + Some errors that are handled this way include "access denied", "not a + directory", or "bad argument to internal function". Thus, the + resulting path may be missing or inaccessible, may still contain + links or loops, and may traverse non-directories. + + This behavior can be modified by keyword arguments: + + If *strict* is ``True``, the first error encountered when evaluating the path is + re-raised. + In particular, :exc:`FileNotFoundError` is raised if *path* does not exist, + or another :exc:`OSError` if it is otherwise inaccessible. + + If *strict* is :py:data:`os.path.ALLOW_MISSING`, errors other than + :exc:`FileNotFoundError` are re-raised (as with ``strict=True``). + Thus, the returned path will not contain any symbolic links, but the named + file and some of its parent directories may be missing. .. note:: This function emulates the operating system's procedure for making a path @@ -429,6 +446,15 @@ the :mod:`glob` module.) .. versionchanged:: 3.10 The *strict* parameter was added. + .. versionchanged:: next + The :py:data:`~os.path.ALLOW_MISSING` value for the *strict* parameter + was added. + +.. data:: ALLOW_MISSING + + Special value used for the *strict* argument in :func:`realpath`. + + .. versionadded:: next .. function:: relpath(path, start=os.curdir) diff --git a/Doc/library/python.rst b/Doc/library/python.rst index c2c231af7c3..c5c762e11b9 100644 --- a/Doc/library/python.rst +++ b/Doc/library/python.rst @@ -27,3 +27,8 @@ overview: inspect.rst annotationlib.rst site.rst + +.. seealso:: + + * See the :mod:`concurrent.interpreters` module, which similarly + exposes core runtime functionality. diff --git a/Doc/library/shelve.rst b/Doc/library/shelve.rst index 6e74a59b82b..23a2e0c3d0c 100644 --- a/Doc/library/shelve.rst +++ b/Doc/library/shelve.rst @@ -75,8 +75,15 @@ Two additional methods are supported: Write back all entries in the cache if the shelf was opened with *writeback* set to :const:`True`. Also empty the cache and synchronize the persistent - dictionary on disk, if feasible. This is called automatically when the shelf - is closed with :meth:`close`. + dictionary on disk, if feasible. This is called automatically when + :meth:`reorganize` is called or the shelf is closed with :meth:`close`. + +.. method:: Shelf.reorganize() + + Calls :meth:`sync` and attempts to shrink space used on disk by removing empty + space resulting from deletions. + + .. versionadded:: next .. method:: Shelf.close() @@ -116,6 +123,11 @@ Restrictions * On macOS :mod:`dbm.ndbm` can silently corrupt the database file on updates, which can cause hard crashes when trying to read from the database. +* :meth:`Shelf.reorganize` may not be available for all database packages and + may temporarely increase resource usage (especially disk space) when called. + Additionally, it will never run automatically and instead needs to be called + explicitly. + .. class:: Shelf(dict, protocol=None, writeback=False, keyencoding='utf-8') diff --git a/Doc/library/socket.rst b/Doc/library/socket.rst index 75fd637045d..bc89a3228f0 100644 --- a/Doc/library/socket.rst +++ b/Doc/library/socket.rst @@ -1492,7 +1492,7 @@ The :mod:`socket` module also offers various network-related services: The *fds* parameter is a sequence of file descriptors. Consult :meth:`~socket.sendmsg` for the documentation of these parameters. - .. availability:: Unix, Windows, not WASI. + .. availability:: Unix, not WASI. Unix platforms supporting :meth:`~socket.sendmsg` and :const:`SCM_RIGHTS` mechanism. @@ -1506,9 +1506,9 @@ The :mod:`socket` module also offers various network-related services: Return ``(msg, list(fds), flags, addr)``. Consult :meth:`~socket.recvmsg` for the documentation of these parameters. - .. availability:: Unix, Windows, not WASI. + .. availability:: Unix, not WASI. - Unix platforms supporting :meth:`~socket.sendmsg` + Unix platforms supporting :meth:`~socket.recvmsg` and :const:`SCM_RIGHTS` mechanism. .. versionadded:: 3.9 diff --git a/Doc/library/sqlite3.rst b/Doc/library/sqlite3.rst index 2d0f9a740c6..12761baf792 100644 --- a/Doc/library/sqlite3.rst +++ b/Doc/library/sqlite3.rst @@ -1482,7 +1482,9 @@ Cursor objects :type parameters: :class:`dict` | :term:`sequence` :raises ProgrammingError: - If *sql* contains more than one SQL statement. + When *sql* contains more than one SQL statement. + When :ref:`named placeholders <sqlite3-placeholders>` are used + and *parameters* is a sequence instead of a :class:`dict`. If :attr:`~Connection.autocommit` is :data:`LEGACY_TRANSACTION_CONTROL`, @@ -1491,13 +1493,11 @@ Cursor objects and there is no open transaction, a transaction is implicitly opened before executing *sql*. - .. deprecated-removed:: 3.12 3.14 + .. versionchanged:: 3.14 - :exc:`DeprecationWarning` is emitted if + :exc:`ProgrammingError` is emitted if :ref:`named placeholders <sqlite3-placeholders>` are used and *parameters* is a sequence instead of a :class:`dict`. - Starting with Python 3.14, :exc:`ProgrammingError` will - be raised instead. Use :meth:`executescript` to execute multiple SQL statements. @@ -1519,8 +1519,10 @@ Cursor objects :type parameters: :term:`iterable` :raises ProgrammingError: - If *sql* contains more than one SQL statement, - or is not a DML statement. + When *sql* contains more than one SQL statement + or is not a DML statement, + When :ref:`named placeholders <sqlite3-placeholders>` are used + and the items in *parameters* are sequences instead of :class:`dict`\s. Example: @@ -1544,14 +1546,12 @@ Cursor objects .. _RETURNING clauses: https://www.sqlite.org/lang_returning.html - .. deprecated-removed:: 3.12 3.14 + .. versionchanged:: 3.14 - :exc:`DeprecationWarning` is emitted if + :exc:`ProgrammingError` is emitted if :ref:`named placeholders <sqlite3-placeholders>` are used and the items in *parameters* are sequences instead of :class:`dict`\s. - Starting with Python 3.14, :exc:`ProgrammingError` will - be raised instead. .. method:: executescript(sql_script, /) diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst index 31d71031bca..394c302fd35 100644 --- a/Doc/library/stdtypes.rst +++ b/Doc/library/stdtypes.rst @@ -1018,7 +1018,7 @@ operations have the same priority as the corresponding numeric operations. [3]_ | ``s * n`` or | equivalent to adding *s* to | (2)(7) | | ``n * s`` | itself *n* times | | +--------------------------+--------------------------------+----------+ -| ``s[i]`` | *i*\ th item of *s*, origin 0 | \(3) | +| ``s[i]`` | *i*\ th item of *s*, origin 0 | (3)(9) | +--------------------------+--------------------------------+----------+ | ``s[i:j]`` | slice of *s* from *i* to *j* | (3)(4) | +--------------------------+--------------------------------+----------+ @@ -1150,6 +1150,9 @@ Notes: without copying any data and with the returned index being relative to the start of the sequence rather than the start of the slice. +(9) + An :exc:`IndexError` is raised if *i* is outside the sequence range. + .. _typesseq-immutable: @@ -1214,6 +1217,8 @@ accepts integers that meet the value restriction ``0 <= x <= 255``). | ``s[i] = x`` | item *i* of *s* is replaced by | | | | *x* | | +------------------------------+--------------------------------+---------------------+ +| ``del s[i]`` | removes item *i* of *s* | | ++------------------------------+--------------------------------+---------------------+ | ``s[i:j] = t`` | slice of *s* from *i* to *j* | | | | is replaced by the contents of | | | | the iterable *t* | | @@ -1836,6 +1841,14 @@ expression support in the :mod:`re` module). unless an encoding error actually occurs, :ref:`devmode` is enabled or a :ref:`debug build <debug-build>` is used. + For example:: + + >>> encoded_str_to_bytes = 'Python'.encode() + >>> type(encoded_str_to_bytes) + <class 'bytes'> + >>> encoded_str_to_bytes + b'Python' + .. versionchanged:: 3.1 Added support for keyword arguments. @@ -1850,7 +1863,19 @@ expression support in the :mod:`re` module). Return ``True`` if the string ends with the specified *suffix*, otherwise return ``False``. *suffix* can also be a tuple of suffixes to look for. With optional *start*, test beginning at that position. With optional *end*, stop comparing - at that position. + at that position. Using *start* and *end* is equivalent to + ``str[start:end].endswith(suffix)``. For example:: + + >>> 'Python'.endswith('on') + True + >>> 'a tuple of suffixes'.endswith(('at', 'in')) + False + >>> 'a tuple of suffixes'.endswith(('at', 'es')) + True + >>> 'Python is amazing'.endswith('is', 0, 9) + True + + See also :meth:`startswith` and :meth:`removesuffix`. .. method:: str.expandtabs(tabsize=8) @@ -1866,12 +1891,15 @@ expression support in the :mod:`re` module). (``\n``) or return (``\r``), it is copied and the current column is reset to zero. Any other character is copied unchanged and the current column is incremented by one regardless of how the character is represented when - printed. + printed. For example:: >>> '01\t012\t0123\t01234'.expandtabs() '01 012 0123 01234' >>> '01\t012\t0123\t01234'.expandtabs(4) '01 012 0123 01234' + >>> print('01\t012\n0123\t01234'.expandtabs(4)) + 01 012 + 0123 01234 .. method:: str.find(sub[, start[, end]]) diff --git a/Doc/library/string.rst b/Doc/library/string.rst index c4012483a52..23e15780075 100644 --- a/Doc/library/string.rst +++ b/Doc/library/string.rst @@ -328,7 +328,7 @@ The general form of a *standard format specifier* is: sign: "+" | "-" | " " width_and_precision: [`width_with_grouping`][`precision_with_grouping`] width_with_grouping: [`width`][`grouping`] - precision_with_grouping: "." [`precision`][`grouping`] + precision_with_grouping: "." [`precision`][`grouping`] | "." `grouping` width: `~python-grammar:digit`+ precision: `~python-grammar:digit`+ grouping: "," | "_" diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst index 55e442b20ff..71f9999464a 100644 --- a/Doc/library/sys.rst +++ b/Doc/library/sys.rst @@ -1933,6 +1933,13 @@ always available. Unless explicitly noted otherwise, all variables are read-only interpreter is pre-release (alpha, beta, or release candidate) then the local and remote interpreters must be the same exact version. + .. audit-event:: remote_debugger_script script_path + + When the script is executed in the remote process, an + :ref:`auditing event <auditing>` + ``sys.remote_debugger_script`` is raised + with the path in the remote process. + .. availability:: Unix, Windows. .. versionadded:: 3.14 diff --git a/Doc/library/tarfile.rst b/Doc/library/tarfile.rst index f9cb5495e60..7cec108a5bd 100644 --- a/Doc/library/tarfile.rst +++ b/Doc/library/tarfile.rst @@ -255,6 +255,15 @@ The :mod:`tarfile` module defines the following exceptions: Raised to refuse extracting a symbolic link pointing outside the destination directory. +.. exception:: LinkFallbackError + + Raised to refuse emulating a link (hard or symbolic) by extracting another + archive member, when that member would be rejected by the filter location. + The exception that was raised to reject the replacement member is available + as :attr:`!BaseException.__context__`. + + .. versionadded:: next + The following constants are available at the module level: @@ -1068,6 +1077,12 @@ reused in custom filters: Implements the ``'data'`` filter. In addition to what ``tar_filter`` does: + - Normalize link targets (:attr:`TarInfo.linkname`) using + :func:`os.path.normpath`. + Note that this removes internal ``..`` components, which may change the + meaning of the link if the path in :attr:`!TarInfo.linkname` traverses + symbolic links. + - :ref:`Refuse <tarfile-extraction-refuse>` to extract links (hard or soft) that link to absolute paths, or ones that link outside the destination. @@ -1099,6 +1114,10 @@ reused in custom filters: Note that this filter does not block *all* dangerous archive features. See :ref:`tarfile-further-verification` for details. + .. versionchanged:: next + + Link targets are now normalized. + .. _tarfile-extraction-refuse: @@ -1127,6 +1146,7 @@ Here is an incomplete list of things to consider: * Extract to a :func:`new temporary directory <tempfile.mkdtemp>` to prevent e.g. exploiting pre-existing links, and to make it easier to clean up after a failed extraction. +* Disallow symbolic links if you do not need the functionality. * When working with untrusted data, use external (e.g. OS-level) limits on disk, memory and CPU usage. * Check filenames against an allow-list of characters diff --git a/Doc/library/threading.rst b/Doc/library/threading.rst index 7edcdcabdce..52fefd590da 100644 --- a/Doc/library/threading.rst +++ b/Doc/library/threading.rst @@ -102,7 +102,7 @@ CPU-bound tasks, as only one thread can execute Python bytecode at a time. Despite this, threads remain a useful tool for achieving concurrency in many scenarios. -As of Python 3.13, experimental :term:`free-threaded <free threading>` builds +As of Python 3.13, :term:`free-threaded <free threading>` builds can disable the GIL, enabling true parallel execution of threads, but this feature is not available by default (see :pep:`703`). diff --git a/Doc/library/token.rst b/Doc/library/token.rst index 1f92b5df430..c228006d4c1 100644 --- a/Doc/library/token.rst +++ b/Doc/library/token.rst @@ -51,7 +51,7 @@ The token constants are: .. data:: NAME Token value that indicates an :ref:`identifier <identifiers>`. - Note that keywords are also initially tokenized an ``NAME`` tokens. + Note that keywords are also initially tokenized as ``NAME`` tokens. .. data:: NUMBER diff --git a/Doc/library/typing.rst b/Doc/library/typing.rst index 54cc3ea3311..69df09c7795 100644 --- a/Doc/library/typing.rst +++ b/Doc/library/typing.rst @@ -3500,20 +3500,11 @@ Introspection helpers Evaluate an :class:`annotationlib.ForwardRef` as a :term:`type hint`. This is similar to calling :meth:`annotationlib.ForwardRef.evaluate`, - but unlike that method, :func:`!evaluate_forward_ref` also: - - * Recursively evaluates forward references nested within the type hint. - * Raises :exc:`TypeError` when it encounters certain objects that are - not valid type hints. - * Replaces type hints that evaluate to :const:`!None` with - :class:`types.NoneType`. - * Supports the :attr:`~annotationlib.Format.FORWARDREF` and - :attr:`~annotationlib.Format.STRING` formats. + but unlike that method, :func:`!evaluate_forward_ref` also + recursively evaluates forward references nested within the type hint. See the documentation for :meth:`annotationlib.ForwardRef.evaluate` for - the meaning of the *owner*, *globals*, *locals*, and *type_params* parameters. - *format* specifies the format of the annotation and is a member of - the :class:`annotationlib.Format` enum. + the meaning of the *owner*, *globals*, *locals*, *type_params*, and *format* parameters. .. versionadded:: 3.14 @@ -3539,28 +3530,32 @@ Constant .. data:: TYPE_CHECKING A special constant that is assumed to be ``True`` by 3rd party static - type checkers. It is ``False`` at runtime. + type checkers. It's ``False`` at runtime. + + A module which is expensive to import, and which only contain types + used for typing annotations, can be safely imported inside an + ``if TYPE_CHECKING:`` block. This prevents the module from actually + being imported at runtime; annotations aren't eagerly evaluated + (see :pep:`649`) so using undefined symbols in annotations is + harmless--as long as you don't later examine them. + Your static type analysis tool will set ``TYPE_CHECKING`` to + ``True`` during static type analysis, which means the module will + be imported and the types will be checked properly during such analysis. Usage:: if TYPE_CHECKING: import expensive_mod - def fun(arg: 'expensive_mod.SomeType') -> None: + def fun(arg: expensive_mod.SomeType) -> None: local_var: expensive_mod.AnotherType = other_fun() - The first type annotation must be enclosed in quotes, making it a - "forward reference", to hide the ``expensive_mod`` reference from the - interpreter runtime. Type annotations for local variables are not - evaluated, so the second annotation does not need to be enclosed in quotes. - - .. note:: - - If ``from __future__ import annotations`` is used, - annotations are not evaluated at function definition time. - Instead, they are stored as strings in ``__annotations__``. - This makes it unnecessary to use quotes around the annotation - (see :pep:`563`). + If you occasionally need to examine type annotations at runtime + which may contain undefined symbols, use + :meth:`annotationlib.get_annotations` with a ``format`` parameter + of :attr:`annotationlib.Format.STRING` or + :attr:`annotationlib.Format.FORWARDREF` to safely retrieve the + annotations without raising :exc:`NameError`. .. versionadded:: 3.5.2 diff --git a/Doc/library/uuid.rst b/Doc/library/uuid.rst index 8cce6b98cbc..92d58024e84 100644 --- a/Doc/library/uuid.rst +++ b/Doc/library/uuid.rst @@ -257,6 +257,10 @@ The :mod:`uuid` module defines the following functions: non-specified arguments are substituted for a pseudo-random integer of appropriate size. + By default, *a*, *b* and *c* are not generated by a cryptographically + secure pseudo-random number generator (CSPRNG). Use :func:`uuid4` when + a UUID needs to be used in a security-sensitive context. + .. versionadded:: 3.14 diff --git a/Doc/library/zlib.rst b/Doc/library/zlib.rst index 75ead3c4cb1..7c5e9b086e1 100644 --- a/Doc/library/zlib.rst +++ b/Doc/library/zlib.rst @@ -44,6 +44,20 @@ The available exception and functions in this module are: .. versionchanged:: 3.0 The result is always unsigned. +.. function:: adler32_combine(adler1, adler2, len2, /) + + Combine two Adler-32 checksums into one. + + Given the Adler-32 checksum *adler1* of a sequence ``A`` and the + Adler-32 checksum *adler2* of a sequence ``B`` of length *len2*, + return the Adler-32 checksum of ``A`` and ``B`` concatenated. + + This function is typically useful to combine Adler-32 checksums + that were concurrently computed. To compute checksums sequentially, use + :func:`adler32` with the running checksum as the ``value`` argument. + + .. versionadded:: next + .. function:: compress(data, /, level=-1, wbits=MAX_WBITS) Compresses the bytes in *data*, returning a bytes object containing compressed data. @@ -136,6 +150,20 @@ The available exception and functions in this module are: .. versionchanged:: 3.0 The result is always unsigned. +.. function:: crc32_combine(crc1, crc2, len2, /) + + Combine two CRC-32 checksums into one. + + Given the CRC-32 checksum *crc1* of a sequence ``A`` and the + CRC-32 checksum *crc2* of a sequence ``B`` of length *len2*, + return the CRC-32 checksum of ``A`` and ``B`` concatenated. + + This function is typically useful to combine CRC-32 checksums + that were concurrently computed. To compute checksums sequentially, use + :func:`crc32` with the running checksum as the ``value`` argument. + + .. versionadded:: next + .. function:: decompress(data, /, wbits=MAX_WBITS, bufsize=DEF_BUF_SIZE) Decompresses the bytes in *data*, returning a bytes object containing the |