Ruijie Yu via "General discussions about Org-mode." <emacs-orgmode@gnu.org> writes:

> Axel Kielhorn <org-mode@axelkielhorn.de> writes:
>
>> Hello!
>>
>> I’m building org with LANG=de.
>> As a result I get two failed tests:
>
> Reproducible using "LANG=zh_CN.UTF-8".  In fact, I got more failed tests
> in my testing.  I think the OP's two test failures are due to hardcoded
> English expected result, whereas the additional test failures on my
> testing are probably due to the fact that each Chinese character is as
> wide as two latin letters, which catches some testing code offguard.
>
> Here are the test names that failed unexpectedly for me.  All the
> "should"'s and "should-not"'s are in the attachment below.
>
> --8<---------------cut here---------------start------------->8---
> 8 unexpected results:
>    FAILED  test-org-clock/clock-drawer-dwim
>    FAILED  test-org-clock/clocktable/lang
>    FAILED  test-org-clok/org-clock-timestamps-change
>    FAILED  test-org-colview/columns-width
>    FAILED  test-org/add-planning-info
>    FAILED  test-org/clone-with-time-shift
>    FAILED  test-org/deadline
>    FAILED  test-org/schedule
> --8<---------------cut here---------------end--------------->8---
>
> [3. text/plain; lang.txt]...

Update: interestingly, there is one test error when setting
"LANG=en_US.UTF-8" or "LANG=C".