Fix "Subject too long" message

[andreyv]

Fixes #1040. Also update .pot file.

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This change is 

[codecov]

Codecov Report

Merging #1041 into master will decrease coverage by 0.05%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1041      +/-   ##
==========================================
- Coverage   62.02%   61.97%   -0.06%     
==========================================
  Files         227      227              
  Lines       16411    16411              
==========================================
- Hits        10179    10170       -9     
- Misses       6232     6241       +9

Flag	Coverage Δ
#functionaltests	46.06% <ø> (-0.02%)	⬇️
#unittests	43.17% <ø> (ø)	⬆️

Impacted Files	Coverage Δ
cms/server/contest/communication.py	100% <ø> (ø)	⬆️
cms/grading/Job.py	79.14% <0%> (-10.43%)	⬇️
cms/db/base.py	89.47% <0%> (-2.11%)	⬇️
cms/io/rpc.py	91.12% <0%> (-0.69%)	⬇️
cms/service/ProxyService.py	57.97% <0%> (-0.54%)	⬇️
cms/service/EvaluationService.py	66.75% <0%> (-0.54%)	⬇️
cms/grading/Sandbox.py	68.23% <0%> (-0.19%)	⬇️
cms/server/admin/handlers/dataset.py	25.38% <0%> (ø)	⬆️
cms/db/filecacher.py	78.21% <0%> (+0.33%)	⬆️
cms/db/util.py	50.75% <0%> (+0.75%)	⬆️
... and 5 more

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[lw]

N_ is only used to mark a message for translation; the actual translation (in this case) is done inside the add_notification method of ContestHandler. The changes you propose have an issue: the message that is marked and that thus appears in cms.pot is of the form text %(foo)d, however the one that is translated is of the form text 42, because the formatting happens after the marking but before calling add_notification. This means that the message won't be translated since it won't be found in cms.pot.

There's no obvious solution to that. The only one I see is to add a new field to UnacceptableQuestion and a new argument to notify_error and add_notification. This field/argument, named for example text_args, would contain the formatting arguments, while the text would now remain unformatted. This way the replacement can be done inside add_notification, rather than when the exception is created. This same problem also affects the other UnacceptableSth exceptions, it would be great if you could fix all of them.

[lw]

To be clear: the issue (a big one) is in our code, this PR uncovered and addressed one symptom but didn't fix the core problem.

[andreyv]

Thanks for the explanation, I confused N_ with _. I'll re-work the PR.

[stefano-maggiolo]

Hi Andrey, do you have time to fix this up today or tomorrow? We'd like to include this fix in rc1 and to release it asap as there were a few substantial usability bugs in rc0. If not it's not a problem, I think Luca can work on it 😁

[lw]

Superseded by #1046.