gh-53203: Fix strptime() for %c and %x formats on many locales (GH-124946)

In some locales (like French or Hebrew) the full or abbreviated names of
the default month and weekday used in __calc_date_time can be part of
other name or constant part of the %c format. The month name can also
match %m with constant suffix (like in Japanese). So the code failed to
correctly distinguish formats %a, %A, %b, %B and %m.

Cycle all month and all days of the week to find the variable part
and distinguish %a from %A and %b from %B or %m.

Fixed locales for the following languges:
Arabic, Bislama, Breton, Bodo, Kashubian, Chuvash, Estonian, French, Irish,
Ge'ez, Gurajati, Manx Gaelic, Hebrew, Hindi, Chhattisgarhi, Haitian Kreyol,
Japanese, Kannada, Korean, Marathi, Malay, Norwegian, Nynorsk, Punjabi,
Rajasthani, Tok Pisin, Yoruba, Yue Chinese, Yau/Nungon and Chinese.

Co-authored-by: Eli Bendersky <eliben@gmail.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/Misc/NEWS.d/next/Library/2024-10-03-20-45-57.gh-issue-53203.3Sk4Ia.rst b/Misc/NEWS.d/next/Library/2024-10-03-20-45-57.gh-issue-53203.3Sk4Ia.rst
new file mode 100644
index 0000000..6895cff
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+++ b/Misc/NEWS.d/next/Library/2024-10-03-20-45-57.gh-issue-53203.3Sk4Ia.rst
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+Fix :func:`time.strptime` for ``%c`` and ``%x`` formats in many locales:
+Arabic, Bislama, Breton, Bodo, Kashubian, Chuvash, Estonian, French, Irish,
+Ge'ez, Gurajati, Manx Gaelic, Hebrew, Hindi, Chhattisgarhi, Haitian Kreyol,
+Japanese, Kannada, Korean, Marathi, Malay, Norwegian, Nynorsk, Punjabi,
+Rajasthani, Tok Pisin, Yoruba, Yue Chinese, Yau/Nungon and Chinese.