"B" symbol in pattern of dayperiod is not supported

[jun66j5]

Overview Description

(Originally reported in https://trac.edgewall.org/ticket/13482, running unit tests in Trac with Babel 2.10.1)

Since Babel 2.10.0 (CLDR 41), B symbol is used in datetime pattern for zh_Hant locale, however Babel doesn't support the B symbol.

Steps to Reproduce

>>> from datetime import datetime
>>> import pytz
>>> import babel
>>> from babel import dates
>>> babel.__version__
'2.10.1'
>>> dates.get_time_format('medium', 'zh_Hant')
<DateTimePattern 'Bh:mm:ss'>
>>> t1 = datetime(2010, 8, 28, 1, 45, 56, 0, pytz.UTC)
>>> t2 = datetime(2010, 8, 28, 13, 45, 56, 0, pytz.UTC)
>>> s1 = dates.format_datetime(t1, 'medium', t1.tzinfo, 'zh_Hant')
>>> s1
'2010年8月28日 B1:45:56'
>>> s2 = dates.format_datetime(t2, 'medium', t1.tzinfo, 'zh_Hant')
>>> s2
'2010年8月28日 B1:45:56'
>>> t1 == t2
False
>>> s1 == s2
True

Actual Results

The B symbol is not formatted.

Expected Results

The B symbol should be formatted to 上午 (am) or 下午 (pm).

Reproducibility

100%

Additional Information

n/a

[jun66j5]

Only zh_Hant and zh_Hant_TW use B symbol for time format in Babel 2.10.1 (CLDR 41).

>>> import babel
>>> babel.__version__
'2.10.1'
>>> from babel.localedata import locale_identifiers
>>> from babel import dates
>>> for locale in locale_identifiers():
...   for format_ in formats:
...     pattern = dates.get_time_format(format=format_, locale=locale)
...     if 'b' in pattern.pattern or 'B' in pattern.pattern:
...       print(locale, width, pattern)
...
zh_Hant_TW full Bh:mm:ss [zzzz]
zh_Hant_TW full Bh:mm:ss [z]
zh_Hant_TW full Bh:mm:ss
zh_Hant_TW full Bh:mm
zh_Hant full Bh:mm:ss [zzzz]
zh_Hant full Bh:mm:ss [z]
zh_Hant full Bh:mm:ss
zh_Hant full Bh:mm

I noticed TODO comments for the b* and B* symbols in DateTimeFormat.__getitem__(). I'll try to fix if anyone has no interests about fix for the issue.

https://github.com/python-babel/babel/blob/v2.10.1/babel/dates.py#L1316-L1318

[akx]

Thanks for the bug report and analysis.

A PR would be appreciated!

[jun66j5]

Okay. I'm trying to fix it.... Hmm, I found the following change has been applied to test_zh_TW_format() while merging PR #826.

-    assert dates.format_time(datetime(2016, 4, 8, 12, 34, 56), locale='zh_TW') == u'\u4e0b\u534812:34:56'
+    assert dates.format_time(datetime(2016, 4, 8, 12, 34, 56), locale='zh_TW') == u'B12:34:56'

[akx]

Okay. I'm trying to fix it.... Hmm, I found the following change has been applied to test_zh_TW_format() while merging PR #826.

That's an oversight on my part, sorry. I should have realized the B is wrong there. That test change should of course be reverted once the B character is supported.

[jun66j5]

I've posted pull request #869 for this issue.

[akx]

Closed via #869. Thank you!