A small example of what a full date and time would look like would help a lot of developers who may not realize that they should investigate `time.h`'s `strftime`, run `man strftime`, or click through a series of docs on the python docs before they get to the actual [definition here](https://docs.python.org/3/library/datetime.html#strftime-and-strptime-format-codes) which still doesn't have an obvious copy-pastable example of "what the heck format does this thing actually expect?".
Automerge-Triggered-By: GH:rhettinger
datetime.isoformat generates the tzoffset with colons, but there
was no format code to make strftime output the same format.
for simplicity and consistency the %:z formatting behaves mostly
as %z, with the exception of adding colons. this includes the
dynamic behaviour of adding seconds and microseconds only when
needed (when not 0).
this fixes the still open "generate" part of this issue:
https://github.com/python/cpython/issues/69142
Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
The `utc_to_seconds` call can fail, here's a minimal reproducer on
Linux:
TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)"
The old behavior still raised an error in a similar way, but only
because subsequent calculations happened to fail as well. Better to fail
fast.
This also refactors the tests to split out the `fromtimestamp` and
`utcfromtimestamp` tests, and to get us closer to the actual desired
limits of the functions. As part of this, we also changed the way we
detect platforms where the same limits don't necessarily apply (e.g.
Windows).
As part of refactoring the tests to hit this condition explicitly (even
though the user-facing behvior doesn't change in any way we plan to
guarantee), I noticed that there was a difference in the places that
`datetime.utcfromtimestamp` fails in the C and pure Python versions, which
was fixed by skipping the "probe for fold" logic for UTC specifically —
since UTC doesn't have any folds or gaps, we were never going to find a
fold value anyway. This should prevent some failures in the pure python
`utcfromtimestamp` method on timestamps close to 0001-01-01.
There are two separate news entries for this because one is a
potentially user-facing change, the other is an internal code
correctness change that, if anything, changes some error messages. The
two happen to be coupled because of the test refactoring, but they are
probably best thought of as independent changes.
Fixes GH-91581
Copying and pickling instances of subclasses of builtin types
bytearray, set, frozenset, collections.OrderedDict, collections.deque,
weakref.WeakSet, and datetime.tzinfo now copies and pickles instance attributes
implemented as slots.
{date, datetime}.isocalendar() now return a private custom named tuple object
IsoCalendarDate rather than a simple tuple.
In order to leave IsocalendarDate as a private class and to improve what
backwards compatibility is offered for pickling the result of a
datetime.isocalendar() call, add a __reduce__ method to the named tuples that
reduces them to plain tuples. (This is the part of this PR most likely to cause
problems — if it causes major issues, switching to a strucseq or equivalent
would be prudent).
The pure python implementation of IsoCalendarDate uses positional-only
arguments, since it is private and only constructed by position anyway; the
equivalent change in the argument clinic on the C side would require us to move
the forward declaration of the type above the clinic import for whatever
reason, so it seems preferable to hold off on that for now.
bpo-24416: https://bugs.python.org/issue24416
Original PR by Dong-hee Na with only minor alterations by Paul Ganssle.
Co-authored-by: Dong-hee Na <donghee.na92@gmail.com>
This fixes an inconsistency between the Python and C implementations of
the datetime module. The pure python version of the code was not
accepting offsets greater than 23:59 but less than 24:00. This is an
accidental legacy of the original implementation, which was put in place
before tzinfo allowed sub-minute time zone offsets.
GH-14878
There was a discrepancy between the Python and C implementations.
Add singletons ALWAYS_EQ, LARGEST and SMALLEST in test.support
to test mixed type comparison.
Returns NotImplemented for timedelta and time in __eq__ for different types in Python implementation, which matches the C implementation.
This also adds tests to enforce that these objects will fall back to the right hand side's __eq__ and/or __ne__ implementation.
bpo-37579
* Make timedelta return subclass types
Previously timedelta would always return the `date` and `datetime`
types, regardless of what it is added to. This makes it return
an object of the type it was added to.
* Add tests for timedelta arithmetic on subclasses
* Make pure python timedelta return subclass types
* Add test for fromtimestamp with tz argument
* Add tests for subclass behavior in now
* Add news entry.
Fixes:
bpo-32417
bpo-35364
* More descriptive variable names in tests
Addresses Victor's comments
* Use _PyUnicode_Copy in sanitize_isoformat_str
* Use repr in fromisoformat error message
This reverses commit 67b74a98b2 per Serhiy Storchaka's suggestion:
I suggested to use %R in the error message because including the raw
string can be confusing in the case of empty string, or string
containing trailing whitespaces, invisible or unprintable characters.
We agree that it is better to change both the C and pure Python versions
to use repr.
* Retain non-sanitized dtstr for error printing
This does not create an extra string, it just holds on to a reference to
the original input string for purposes of creating the error message.
* PEP 7 fixes to from_isoformat
* Separate handling of Unicode and other errors
In the initial implementation, errors other than encoding errors would
both raise an error indicating an invalid format, which would not be
true for errors like MemoryError.
* Drop needs_decref from _sanitize_isoformat_str
Instead _sanitize_isoformat_str returns a new reference, even to the
original string.
On Windows, passing a negative value to local results in an OSError because localtime_s on Windows does not support negative timestamps. Unfortunately this means that fold detection for timestamps between 0 and max_fold_seconds will result in this OSError since we subtract max_fold_seconds from the timestamp to detect a fold. However, since we know there haven't been any folds in the interval [0, max_fold_seconds) in any timezone, we can hackily just forego fold detection for this time range on Windows.
A datetime object d is aware if d.tzinfo is not None and
d.tzinfo.utcoffset(d) does not return None. If d.tzinfo is None,
or if d.tzinfo is not None but d.tzinfo.utcoffset(d) returns None,
d is naive.
This commit ensures that instances with non-None d.tzinfo, but
d.tzinfo.utcoffset(d) returning None are treated as naive.
In addition, C acceleration code will raise TypeError if
d.tzinfo.utcoffset(d) returns an object with the type other than
timedelta.
* Updated the documentation.
Assume that the term "naive" is defined elsewhere and remove the
not entirely correct clarification. Thanks, Tim.
Since implementation of bpo-25283, the objects returned by time.localtime
always have tm_zone and tm_gmtoff attributes. Remove code that
anticipates their absence.
* Closes issue bpo-5288: Allow tzinfo objects with sub-minute offsets.
* bpo-5288: Implemented %z formatting of sub-minute offsets.
* bpo-5288: Removed mentions of the whole minute limitation on TZ offsets.
* bpo-5288: Removed one more mention of the whole minute limitation.
Thanks @csabella!
* Fix a formatting error in the docs
* Addressed review comments.
Thanks, @haypo.
Added an optional argument timespec to the datetime isoformat() method
to choose the precision of the time component.
Original patch by Alessandro Cucci.
of datetime.datetime: microseconds are now rounded to nearest with ties going
to nearest even integer (ROUND_HALF_EVEN), instead of being rounding towards
zero (ROUND_DOWN). It's important that these methods use the same rounding
mode than datetime.timedelta to keep the property:
(datetime(1970,1,1) + timedelta(seconds=t)) == datetime.utcfromtimestamp(t)
It also the rounding mode used by round(float) for example.
Add more unit tests on the rounding mode in test_datetime.
datetime.datetime now round microseconds to nearest with ties going to nearest
even integer (ROUND_HALF_EVEN), as round(float), instead of rounding towards
-Infinity (ROUND_FLOOR).
pytime API: replace _PyTime_ROUND_HALF_UP with _PyTime_ROUND_HALF_EVEN. Fix
also _PyTime_Divide() for negative numbers.
_PyTime_AsTimeval_impl() now reuses _PyTime_Divide() instead of reimplementing
rounding modes.
"""Issue #23517: datetime.timedelta constructor now rounds microseconds to
nearest with ties going away from zero (ROUND_HALF_UP), as Python 2 and Python
older than 3.3, instead of rounding to nearest with ties going to nearest even
integer (ROUND_HALF_EVEN)."""
datetime.timedelta uses rounding mode ROUND_HALF_EVEN again.
Alex Waygood
Zackery Spytz
Alex Zvorygin
TW
Paul Ganssle
Kabir Kwatra
Serhiy Storchaka
Harry
scaramallion
Ram Rachum
Paul Ganssle
t k
Ngalim Siregar
Xtreak
Paul Ganssle
Ammar Askar
Alexander Belopolsky
Utkarsh Upadhyay
Victor Stinner
Alexander Belopolsky
Martin Panter
Brett Cannon