Fix UTF-8 handling for strftime format strings

[designet-inc-oss]

Summary

On AlmaLinux 10, Japanese characters in format strings passed to POSIX::strftime() are handled differently from AlmaLinux 9.

When a Japanese character is included in the format string, strftime() can return a string with the UTF-8 flag enabled while the underlying data is still UTF-8 encoded bytes.

This can cause Japanese characters to become garbled when Encode::_utf8_off() is subsequently called.

Change

Decode the format string as UTF-8 before passing it to POSIX::strftime().

$format = $self->gettext($format);
$format = Encode::decode('UTF-8', $format);

Verification

The behavior was reproduced on AlmaLinux 10 using a format string containing Japanese characters.

Before this change, the following behavior was observed:

format:
UTF8 flag = OFF
bytes = 30.E5.B9.B4.30

after strftime():
UTF8 flag = ON
bytes = 30.E5.B9.B4.30

after Encode::_utf8_off():
0å¹´0

After decoding the format string before calling strftime():

format:
UTF8 flag = ON
Unicode character U+5E74

after strftime():
UTF8 flag = ON
Unicode character U+5E74

after Encode::_utf8_off():
0年0

The same test on AlmaLinux 9 produces the expected Unicode string from strftime() without this additional conversion.

This change makes the format string explicitly a Unicode string before it is passed to strftime(), and prevents the character encoding mismatch observed on AlmaLinux 10.

Scope

This change only adds UTF-8 decoding of the localized format string before the existing strftime() processing.

[ikedas]

@designet-inc-oss ,
すみませんがそちらの環境 (新旧とも) での次のもののバージョンを教えてください。
Could you please show us the version information of these things on your environment (both of Alma 9 and 10)？

• Perl (and if possible, POSIX module)
• Locale-Messages Perl module

[designet-inc-oss]

それぞれの環境に入っているバージョンは以下になります。

AlmaLinux 9.8

Perl: 5.32.1
POSIX: 1.94
Locale::Messages: 1.32

AlmaLinux10.2

Perl: 5.40.2
POSIX: 2.20
Locale::Messages: 1.33