Merge tag v3.8.0b1 into main-slp

Author: Anselm Kruis

Doc/library/asyncio-eventloop.rst

@@ -140,18 +140,12 @@ Running and stopping the loop
    The loop must not be running when this function is called.
    Any pending callbacks will be discarded.
 
-   This method clears all queues and shuts down the default executor. By
-   default, it waits for the default executor to finish. Set
-   *loop.wait_executor_on_close* to ``False`` to not wait for the executor.
+   This method clears all queues and shuts down the executor, but does
+   not wait for the executor to finish.
 
    This method is idempotent and irreversible.  No other methods
    should be called after the event loop is closed.
 
-   .. versionchanged:: 3.8
-      The method now waits for the default executor to finish by default.
-      Added *loop.wait_executor_on_close* attribute.
-
-
 .. coroutinemethod:: loop.shutdown_asyncgens()
 
    Schedule all currently open :term:`asynchronous generator` objects to

Doc/library/datetime.rst

@@ -1365,56 +1365,64 @@ Examples of working with datetime objects:
 
 Using datetime with tzinfo:
 
-    >>> from datetime import timedelta, datetime, tzinfo
-    >>> class GMT1(tzinfo):
+    >>> from datetime import timedelta, datetime, tzinfo, timezone
+    >>> class KabulTz(tzinfo):
+    ...     # Kabul used +4 until 1945, when they moved to +4:30
+    ...     UTC_MOVE_DATE = datetime(1944, 12, 31, 20, tzinfo=timezone.utc)
     ...     def utcoffset(self, dt):
-    ...         return timedelta(hours=1) + self.dst(dt)
-    ...     def dst(self, dt):
-    ...         # DST starts last Sunday in March
-    ...         d = datetime(dt.year, 4, 1)   # ends last Sunday in October
-    ...         self.dston = d - timedelta(days=d.weekday() + 1)
-    ...         d = datetime(dt.year, 11, 1)
-    ...         self.dstoff = d - timedelta(days=d.weekday() + 1)
-    ...         if self.dston <=  dt.replace(tzinfo=None) < self.dstoff:
-    ...             return timedelta(hours=1)
+    ...         if dt.year < 1945:
+    ...             return timedelta(hours=4)
+    ...         elif (1945, 1, 1, 0, 0) <= dt.timetuple()[:5] < (1945, 1, 1, 0, 30):
+    ...             # If dt falls in the imaginary range, use fold to decide how
+    ...             # to resolve. See PEP495
+    ...             return timedelta(hours=4, minutes=(30 if dt.fold else 0))
     ...         else:
-    ...             return timedelta(0)
-    ...     def tzname(self,dt):
-    ...          return "GMT +1"
+    ...             return timedelta(hours=4, minutes=30)
+    ...
+    ...     def fromutc(self, dt):
+    ...         # A custom implementation is required for fromutc as
+    ...         # the input to this function is a datetime with utc values
+    ...         # but with a tzinfo set to self
+    ...         # See datetime.astimezone or fromtimestamp
+    ...
+    ...         # Follow same validations as in datetime.tzinfo
+    ...         if not isinstance(dt, datetime):
+    ...             raise TypeError("fromutc() requires a datetime argument")
+    ...         if dt.tzinfo is not self:
+    ...             raise ValueError("dt.tzinfo is not self")
+    ...
+    ...         if dt.replace(tzinfo=timezone.utc) >= self.UTC_MOVE_DATE:
+    ...             return dt + timedelta(hours=4, minutes=30)
+    ...         else:
+    ...             return dt + timedelta(hours=4)
     ...
-    >>> class GMT2(tzinfo):
-    ...     def utcoffset(self, dt):
-    ...         return timedelta(hours=2) + self.dst(dt)
     ...     def dst(self, dt):
-    ...         d = datetime(dt.year, 4, 1)
-    ...         self.dston = d - timedelta(days=d.weekday() + 1)
-    ...         d = datetime(dt.year, 11, 1)
-    ...         self.dstoff = d - timedelta(days=d.weekday() + 1)
-    ...         if self.dston <=  dt.replace(tzinfo=None) < self.dstoff:
-    ...             return timedelta(hours=1)
+    ...         return timedelta(0)
+    ...
+    ...     def tzname(self, dt):
+    ...         if dt >= self.UTC_MOVE_DATE:
+    ...             return "+04:30"
     ...         else:
-    ...             return timedelta(0)
-    ...     def tzname(self,dt):
-    ...         return "GMT +2"
+    ...             return "+04"
     ...
-    >>> gmt1 = GMT1()
-    >>> # Daylight Saving Time
-    >>> dt1 = datetime(2006, 11, 21, 16, 30, tzinfo=gmt1)
-    >>> dt1.dst()
-    datetime.timedelta(0)
-    >>> dt1.utcoffset()
-    datetime.timedelta(seconds=3600)
-    >>> dt2 = datetime(2006, 6, 14, 13, 0, tzinfo=gmt1)
-    >>> dt2.dst()
-    datetime.timedelta(seconds=3600)
-    >>> dt2.utcoffset()
-    datetime.timedelta(seconds=7200)
+    ...     def  __repr__(self):
+    ...         return f"{self.__class__.__name__}()"
+    ...
+    >>> tz1 = KabulTz()
+    >>> # Datetime before the change
+    >>> dt1 = datetime(1900, 11, 21, 16, 30, tzinfo=tz1)
+    >>> print(dt1.utcoffset())
+    4:00:00
+    >>> # Datetime after the change
+    >>> dt2 = datetime(2006, 6, 14, 13, 0, tzinfo=tz1)
+    >>> print(dt2.utcoffset())
+    4:30:00
     >>> # Convert datetime to another time zone
-    >>> dt3 = dt2.astimezone(GMT2())
-    >>> dt3     # doctest: +ELLIPSIS
-    datetime.datetime(2006, 6, 14, 14, 0, tzinfo=<GMT2 object at 0x...>)
-    >>> dt2     # doctest: +ELLIPSIS
-    datetime.datetime(2006, 6, 14, 13, 0, tzinfo=<GMT1 object at 0x...>)
+    >>> dt3 = dt2.astimezone(timezone.utc)
+    >>> dt3
+    datetime.datetime(2006, 6, 14, 8, 30, tzinfo=datetime.timezone.utc)
+    >>> dt2
+    datetime.datetime(2006, 6, 14, 13, 0, tzinfo=KabulTz())
     >>> dt2.utctimetuple() == dt3.utctimetuple()
     True
 
@@ -1656,26 +1664,27 @@ Instance methods:
 Example:
 
     >>> from datetime import time, tzinfo, timedelta
-    >>> class GMT1(tzinfo):
+    >>> class TZ1(tzinfo):
     ...     def utcoffset(self, dt):
     ...         return timedelta(hours=1)
     ...     def dst(self, dt):
     ...         return timedelta(0)
     ...     def tzname(self,dt):
-    ...         return "Europe/Prague"
+    ...         return "+01:00"
+    ...     def  __repr__(self):
+    ...         return f"{self.__class__.__name__}()"
     ...
-    >>> t = time(12, 10, 30, tzinfo=GMT1())
-    >>> t                               # doctest: +ELLIPSIS
-    datetime.time(12, 10, 30, tzinfo=<GMT1 object at 0x...>)
-    >>> gmt = GMT1()
+    >>> t = time(12, 10, 30, tzinfo=TZ1())
+    >>> t
+    datetime.time(12, 10, 30, tzinfo=TZ1())
     >>> t.isoformat()
     '12:10:30+01:00'
     >>> t.dst()
     datetime.timedelta(0)
     >>> t.tzname()
-    'Europe/Prague'
+    '+01:00'
     >>> t.strftime("%H:%M:%S %Z")
-    '12:10:30 Europe/Prague'
+    '12:10:30 +01:00'
     >>> 'The {} is {:%H:%M}.'.format("time", t)
     'The time is 12:10.'
 

Doc/library/math.rst

@@ -41,12 +41,15 @@ Number-theoretic and representation functions
    Return the number of ways to choose *k* items from *n* items without repetition
    and without order.
 
-   Also called the binomial coefficient. It is mathematically equal to the expression
-   ``n! / (k! (n - k)!)``. It is equivalent to the coefficient of the *k*-th term in the
-   polynomial expansion of the expression ``(1 + x) ** n``.
+   Evaluates to ``n! / (k! * (n - k)!)`` when ``k <= n`` and evaluates
+   to zero when ``k > n``.
 
-   Raises :exc:`TypeError` if the arguments not integers.
-   Raises :exc:`ValueError` if the arguments are negative or if *k* > *n*.
+   Also called the binomial coefficient because it is equivalent
+   to the coefficient of k-th term in polynomial expansion of the
+   expression ``(1 + x) ** n``.
+
+   Raises :exc:`TypeError` if either of the arguments are not integers.
+   Raises :exc:`ValueError` if either of the arguments are negative.
 
    .. versionadded:: 3.8
 
@@ -212,10 +215,11 @@ Number-theoretic and representation functions
    Return the number of ways to choose *k* items from *n* items
    without repetition and with order.
 
-   It is mathematically equal to the expression ``n! / (n - k)!``.
+   Evaluates to ``n! / (n - k)!`` when ``k <= n`` and evaluates
+   to zero when ``k > n``.
 
-   Raises :exc:`TypeError` if the arguments not integers.
-   Raises :exc:`ValueError` if the arguments are negative or if *k* > *n*.
+   Raises :exc:`TypeError` if either of the arguments are not integers.
+   Raises :exc:`ValueError` if either of the arguments are negative.
 
    .. versionadded:: 3.8
 

Doc/reference/simple_stmts.rst

@@ -330,10 +330,9 @@ statement, of a variable or attribute annotation and an optional assignment stat
 
 .. productionlist::
    annotated_assignment_stmt: `augtarget` ":" `expression`
-                            : ["=" (`expression_list` | `yield_expression`)]
+                            : ["=" (`starred_expression` | `yield_expression`)]
 
-The difference from normal :ref:`assignment` is that only single target and
-only single right hand side value is allowed.
+The difference from normal :ref:`assignment` is that only single target is allowed.
 
 For simple names as assignment targets, if in class or module scope,
 the annotations are evaluated and stored in a special class or module
@@ -369,7 +368,7 @@ target, then the interpreter evaluates the target except for the last
 
 .. versionchanged:: 3.8
    Now annotated assignments allow same expressions in the right hand side as
-   the augmented assignments. Previously, some expressions (like un-parenthesized
+   the regular assignments. Previously, some expressions (like un-parenthesized
    tuple expressions) caused a syntax error.
 
 

Doc/tools/extensions/pyspecific.py

@@ -36,7 +36,7 @@
 
 
 ISSUE_URI = 'https://bugs.python.org/issue%s'
-SOURCE_URI = 'https://github.com/python/cpython/tree/master/%s'
+SOURCE_URI = 'https://github.com/python/cpython/tree/3.8/%s'
 
 # monkey-patch reST parser to disable alphabetic and roman enumerated lists
 from docutils.parsers.rst.states import Body

Include/patchlevel.h

@@ -19,11 +19,11 @@
 #define PY_MAJOR_VERSION        3
 #define PY_MINOR_VERSION        8
 #define PY_MICRO_VERSION        0
-#define PY_RELEASE_LEVEL        PY_RELEASE_LEVEL_ALPHA
-#define PY_RELEASE_SERIAL       4
+#define PY_RELEASE_LEVEL        PY_RELEASE_LEVEL_BETA
+#define PY_RELEASE_SERIAL       1
 
 /* Version as a string */
-#define PY_VERSION              "3.8.0a4+"
+#define PY_VERSION              "3.8.0b1"
 /*--end constants--*/
 
 /* Version as a single 4-byte hex number, e.g. 0x010502B2 == 1.5.2b2.

Lib/asyncio/base_events.py

@@ -380,8 +380,6 @@ async def wait_closed(self):
 class BaseEventLoop(events.AbstractEventLoop):
 
     def __init__(self):
-        # If true, close() waits for the default executor to finish
-        self.wait_executor_on_close = True
         self._timer_cancelled_count = 0
         self._closed = False
         self._stopping = False
@@ -637,7 +635,7 @@ def close(self):
         executor = self._default_executor
         if executor is not None:
             self._default_executor = None
-            executor.shutdown(wait=self.wait_executor_on_close)
+            executor.shutdown(wait=False)
 
     def is_closed(self):
         """Returns True if the event loop was closed."""

Lib/logging/handlers.py

@@ -1437,7 +1437,7 @@ def start(self):
         t.daemon = True
         t.start()
 
-    def prepare(self , record):
+    def prepare(self, record):
         """
         Prepare a record for handling.