allow merging of year and date if identical

[JoKalliauer]

JabRef 5.1--2020-03-23--67daf36
Windows 10 10.0 amd64 
Java 14

% Encoding: UTF-8

@Article{morgenthal2016Concretehingesandintegralbridgepiers,
  author       = {Morgenthal, Guido and Olney, Peter},
  title        = {Concrete hinges and integral bridge piers},
  year         = {2016},
  month        = jan,
  number       = {1},
  pages        = {06015005},
  volume       = {21},
  date         = {2016-01},
  doi          = {10.1061/(ASCE)BE.1943-5592.0000783},
  file         = {:Shared/Literatur Betongelenke/Morgenthal_2015_Concrete Hinges and Integral Bridge Piers.pdf:PDF},
  groups       = {FEMPaper, Betongelenke},
  journaltitle = {Journal of Bridge Engineering},
  keywords     = {rank3},
  owner        = {jkalliau},
  publisher    = {American Society of Civil Engineers},
  ranking      = {rank3},
  timestamp    = {2020-03-26},
}

@Comment{jabref-meta: databaseType:biblatex;}

Steps to reproduce the behavior:

1. open bibtex2biblatexBugJK.bib.txt
2. clean up using following settings
   

year does not get removed

[catarinagomespt]

Hi,
I would like to contribute to your project.
Is this issue still open, right?

Best regards

[catarinagomespt]

I'd like to collaborate on this issue. I would like additional tips to understand better the problem.

[JoKalliauer]

@catarinagomespt
I'm just a stupid user, so I might be wrong:

Afaik everyone can make a personal fork and edit this fork and then make a pull request to merge your input (afaik, even if the masterbrach changed meanwile)
No one else claimed to start on this issue and it was marked as low priority (which imho means the user can wait for several month-years for a bugfix), therefore it is highly unlikely someone else will fix this issue within the next month. ("Nobody" cared about it the last month, so the following might be the same.)

@ Developers: I know you are volenteering and I'm glad that you developed JabRef. (So don't understand that wrong. I like JabRef, otherwise I would not use it.)

Do you need tips from the developers (code) or from the problem?

I cannot comment on the code, where to look for.

The problem is:

@Article{bibtexkey,
  year         = {2020},
  month        = may,
}

converts to

@Article{bibtexkey,
  date         = {2020-05},
}

but

@Article{bibtexkey,
  year         = {2020},
  month        = may,
  date         = {2020-05},
}

stays the same, and leads to warnings in biber

[Siedlerchr]

Some more background information.
JabRef supports bibtex and biblatex (successor of biblatex). However, biblatex uses the date field and not year month like in bibtex. JabRef therefore threats them as alias fields to allow conversion to biblatex and bibtex
The cleanup in jabref should now offer the possibility to merge the year and month field into date and additionally remove/clear the fields afterward.
Code wise I suggest looking into the Cleanup classes in logic

[catarinagomespt]

Do you need tips from the developers (code) or from the problem?

Thanks @JoKalliauer . I want to understand the problem not the code. I already realized the problem 👍
That was it! Perfect. I also like to thank @Siedlerchr 's feedback.
I will analyze the code.

[tobiasdiez]

Thanks to @catarinagomespt this is now implemented in the latest development version. Could you please check the build from http://builds.jabref.org/master/. Thanks! Please remember to make a backup of your library before trying-out this version.