checked in two days agao:
Refactoring of, and new rules for, dt.astimezone(tz).
dt must be aware now, and tz.utcoffset() and tz.dst() must not return None.
The old dt.astimezone(None) no longer works to change an aware datetime
into a naive datetime; use dt.replace(tzinfo=None) instead.
The tzinfo base class now supplies a new fromutc(self, dt) method, and
datetime.astimezone(tz) invokes tz.fromutc(). The default implementation
of fromutc() reproduces the same results as the old astimezone()
implementation, but tzinfo subclasses can override fromutc() if the
default implementation isn't strong enough to get the correct results
in all cases (for example, this may be necessary if a tzinfo subclass
models a time zone whose "standard offset" (wrt UTC) changed in some
year(s), or in some variations of double-daylight time -- the creativity
of time zone politics can't be captured in a single default implementation).
60: Added support for the SkippedEntityHandler, new in Expat 1.95.4.
61: Added support for namespace prefixes, which can be enabled by setting the
"namespace_prefixes" attribute on the parser object.
65: Disable profiling changes for Python 2.0 and 2.1.
66: Update pyexpat to export the Expat 1.95.5 XML_GetFeatureList()
information, and tighten up a type declaration now that Expat is using
an incomplete type rather than a void * for the XML_Parser type.
67: Clarified a comment.
Added support for XML_UseForeignDTD(), new in Expat 1.95.5.
68: Refactor to avoid partial duplication of the code to construct an
ExpatError instance, and actually conform to the API for the exception
instance as well.
69: Remove some spurious trailing whitespace.
Add a special external-entity-ref handler that gets installed once a
handler has raised a Python exception; this can cancel actual parsing
earlier if there's an external entity reference in the input data
after the the Python excpetion has been raised.
70: Untabify APPEND.
71: Backport PyMODINIT_FUNC for 2.2 and earlier.
When daylight time ends, an hour repeats on the local clock (for example,
in US Eastern, the clock jumps from 1:59 back to 1:00 again). Times in
the repeated hour are ambiguous. A tzinfo subclass that wants to play
with astimezone() needs to treat times in the repeated hour as being
standard time. astimezone() previously required that such times be
treated as daylight time. There seems no killer argument either way,
but Guido wants the standard-time version, and it does seem easier the
new way to code both American (local-time based) and European (UTC-based)
switch rules, and the astimezone() implementation is simpler.
underlying DB has already been closed (and thus all of its cursors).
This fixes a potential segfault.
SF pybsddb bug id 667343
bugfix: close the DB object when raising an exception due to an error
during DB.open. This prevents an exception when closing the
environment about not all databases being closed.
SF pybsddb bug id 667340
hoped it would be, but not too bad. A test had to change:
time.__setstate__() can no longer add a non-None tzinfo member to a time
object that didn't already have one, since storage for a tzinfo member
doesn't exist in that case.
into time. This is little more than *exporting* the datetimetz object
under the name "datetime", and similarly for timetz. A good implementation
of this change requires more work, but this is fully functional if you
don't stare too hard at the internals (e.g., right now a type named
"datetime" shows up as a base class of the type named "datetime"). The
docs also need extensive revision, not part of this checkin.
The attached patch enables shared extension
modules to build cleanly under Cygwin without
moving the static initialization of certain function
pointers (i.e., ones exported from the Python
DLL core) to a module initialization function.
Additionally, this patch fixes the modules that
have been changed in the past to accommodate
Cygwin.
cases, plus even tougher tests of that. This implementation follows
the correctness proof very closely, and should also be quicker (yes,
I wrote the proof before the code, and the code proves the proof <wink>).
Lesson learned: kids should not be allowed to use API's starting
with an underscore :-/
zipimport in 2.3a1 is even more broken than I thought: I attemped
to _PyString_Resize a string created by PyString_FromStringAndSize,
which fails for strings with length 0 or 1 since the latter returns
an interned string in those cases. This would cause a SystemError
with empty source files (and no matching pyc) in the zip archive.
I rewrote the offending code to simply allocate a new buffer and
avoid _PyString_Resize altogether.
Added a test that would've caught the problem.
(or None) now. In 2.3a1 they could also return an int or long, but that
was an unhelpfully redundant leftover from an earlier version wherein
they couldn't return a timedelta. TOOWTDI.
On Windows, it was very common to get microsecond values (out of
.today() and .now()) of the form 480999, i.e. with three trailing
nines. The platform precision is .001 seconds, and fp rounding
errors account for the rest. Under the covers, that 480999 started
life as the fractional part of a timestamp, like .4809999978.
Rounding that times 1e6 cures the irritation.
Confession: the platform precision isn't really .001 seconds. It's
usually worse. What actually happens is that MS rounds a cruder value
to a multiple of .001, and that suffers its own rounding errors.
A tiny bit of refactoring added a new internal utility to round
doubles.
the test set as it only tested with a zip archive in the current directory,
but it doesn't work at all for packages when the zip archive was specified
as an absolute path. It's a real embarrassing bug: a strchr call should
have been strrchr; fever apparently implies dyslexia.
Second stupid bug: the zipimport test failed with a name error
__importer__ (which I had renamed to __loader__ everywhere but here).
I would've sworn I ran the test after that change but that can't be true.
What I don't understand that noone reported a failing test_zipimport.py
before the release of 2.3a1.
suggestion from Guido, along with a formal correctness proof of the
trickiest bit. The intricacy of the proof reveals how delicate this
is, but also how robust the conclusion: correctness doesn't rely on
dst() returning +- one hour (not all real time zones do!), it only
relies on:
1. That dst() returns a (any) non-zero value if and only if daylight
time is in effect.
and
2. That the tzinfo subclass implements a consistent notion of time zone.
The meaning of "consistent" was a hidden assumption, which is now an
explicit requirement in the docs. Alas, it's an unverifiable (by the
datetime implementation) requirement, but so it goes.
find a more elegant algorithm (OTOH, the hairy new implementation allows
user-written tzinfo classes to be elegant, so it's a big win even if
astimezone() remains hairy).
Darn! I've only got 10 minutes left to get falling-down drunk! I suppose
I'll have to smoke crack instead now.
Tim Peters
Martin v. Löwis
Neal Norwitz
Raymond Hettinger
Gregory P. Smith
Jack Jansen
Barry Warsaw
Guido van Rossum
Jason Tishler
Just van Rossum
Andrew MacIntyre