Report errors for duplicate BibTeX entry keys

[pfoerster]

No description provided.

[clason]

Nice! Do duplicate labels next 🙏 :)

[clason]

I just tested this (sorry for not doing so earlier!) and noticed a small nit: If you have duplicate keys, it will only report the error on one of them (the first one in the file?) If it's not hard to implement, it would be even more useful if it marked all of them, so you can check them easily and see if it's a duplicate entry or an accidental ambiguity (say, two different papers that happen to have the same authors and year).

[pfoerster]

If you have duplicate keys, it will only report the error on one of them (the first one in the file?)

Yes, that's intentional. The Diagnostic should have the relatedInformation field populated with the additional occurences of the duplicate key. Maybe, Neovim is not showing it. Here is, how it looks like in VSCode:

[clason]

Ah, I see. As far as I know, Neovim is indeed not doing anything with that field. It would be nice to be able to annotate the duplicate information in the file itself, to be honest. (I also feel that this is a bit unintuitive, since in your example, the actual error is actually on lines 3 and 5, not on line 1?)

[pfoerster]

Maybe, it's easier to report one error for each entry and then link the duplicates via relatedInformation (and do the same thing for labels).

[clason]

I feel that would be the best approach. But it's not a deal-breaker either way! Being able to see any error before trying to compile a huge file (and trashing your aux file in the process) is a huge quality of life gain :)

(If you have multiple bib files, duplicate keys could be in separate files, so this would make sure every file with errors gets marked as such.)

[pfoerster]

@clason I have created a new PR: #908 🚀