issue with en_AU locale

[alec000inspired]

Overview Description

When I use the en_AU locale, the date format for 2023-12-31 places it into W1 of 2023.
I would expect this to be W53 of 2023 or possible W1 of 2024.

Steps to Reproduce

import datetime
import babel
import babel.dates
foo = babel.dates.format_date(datetime.date(year=2023, month=12, day=31), format="'W'w YYYY", locale='en_US')
bar = babel.dates.format_date(datetime.date(year=2023, month=12, day=31), format="'W'w YYYY", locale='en_AU')
print(foo)  # W53 2023 (correct)
print(bar)  # W1 2023 (incorrect)

Actual Results

'W1 2023'

Expected Results

'W53 2023'

[RomainBarbason]

Can i be assigned to this problem ? Thanks !

[tomasr8]

Go for it :)

[jun66j5]

The date formatting for YYYY and ww symbols for the week number with locales that the week starts with Monday (as same as the ISO week) are currently broken.

Also, format_year for YYYY symbol uses date.isocalendar() after #621, so that it is broken with locales that the week starts with except Monday (e.g. US: Sunday, EG: Satday, MV: Friday).

I'll try to fix it....

See also:

• https://www.unicode.org/reports/tr35/tr35-dates.html#dfst-year
• https://www.unicode.org/reports/tr35/tr35-dates.html#dfst-week

>>> date_strings = '2005-01-01 2005-01-02 2005-12-31 2006-01-01 2006-01-02 2006-12-31 2007-01-01 2007-12-30 2007-12-31 2008-01-01 2008-12-28 2008-12-29 2008-12-30 2008-12-31 2009-01-01 2009-12-31 2010-01-01 2010-01-02 2010-01-03'
>>> for d in map(parse_date, date_strings.split()):
...   print('{}  {}  {}'.format(
...     d,
...     '%04d-W%02d-%d' % d.isocalendar(),
...     format_date(d, format="YYYY-'W'ww-e", locale='de_DE'),
...   ))
...
2005-01-01  2004-W53-6  2004-W01-6
2005-01-02  2004-W53-7  2004-W01-7
2005-12-31  2005-W52-6  2005-W52-6
2006-01-01  2005-W52-7  2005-W52-7
2006-01-02  2006-W01-1  2006-W01-1
2006-12-31  2006-W52-7  2006-W52-7
2007-01-01  2007-W01-1  2007-W01-1
2007-12-30  2007-W52-7  2007-W52-7
2007-12-31  2008-W01-1  2008-W01-1
2008-01-01  2008-W01-2  2008-W01-2
2008-12-28  2008-W52-7  2008-W52-7
2008-12-29  2009-W01-1  2009-W01-1
2008-12-30  2009-W01-2  2009-W01-2
2008-12-31  2009-W01-3  2009-W01-3
2009-01-01  2009-W01-4  2009-W01-4
2009-12-31  2009-W53-4  2009-W53-4
2010-01-01  2009-W53-5  2009-W01-5
2010-01-02  2009-W53-6  2009-W01-6
2010-01-03  2009-W53-7  2009-W01-7