Overwrite existing data model in tool mode

[moewew]

It was pointed out to me today that my answer to https://tex.stackexchange.com/q/265895/35864 on TeX.SX ceased to work properly, so I tried to make it work with newer Biber versions.

Consider the following .bib file augustus.bib

@article{kattan_timeseries_2015,
  title = {Time-series event-based prediction: An unsupervised learning framework based on genetic programming},  
  journaltitle = {Information Sciences},
  author = {Kattan, Ahmed and Fatima, Shaheen and Arif, Muhammad},
  date = {2015-04}
}
@book{lorem,
  TITLE = {Lorem},  
  Author = {Anne Uthor},
  DaTe = {2015}
}
@book{ipsum,
  title = {Ipsum},  
  author = {Anne Uthor},
  date = {2015-08-07},
}

With biber-datea.conf

<?xml version="1.0" encoding="UTF-8"?>
<config>
  <output_fieldcase>lower</output_fieldcase>
  <datamodel>
    <fields>
      <field fieldtype="field" datatype="literal">yeara</field>
      <field fieldtype="field" datatype="literal">montha</field>
    </fields>
    <entryfields>
      <field>yeara</field>
      <field>montha</field>
    </entryfields>
  </datamodel>
  <sourcemap>
    <maps datatype="bibtex">
      <map map_overwrite="1">
        <map_step map_field_source="date" map_match="[0-9]{4}-([0-9]{2})" map_final="1"/>
        <map_step map_field_set="montha" map_field_value="$1"/>
      </map>
      <map map_overwrite="1">
        <map_step map_field_source="date" map_match="([0-9]{4})" map_final="1"/>
        <map_step map_field_set="yeara" map_field_value="$1"/>
      </map>
    </maps>
  </sourcemap>
</config>

biber --tool --configfile=biber-datea.conf augustus.bib  

produces

@article{kattan_timeseries_2015,
  author = {Kattan, Ahmed and Fatima, Shaheen and Arif, Muhammad},
  date = {2015-04},
  journaltitle = {Information Sciences},
  montha = {04},
  title = {Time-series event-based prediction: An unsupervised learning framework based on genetic programming},
  yeara = {2015},
}

@book{lorem,
  author = {Uthor, Anne},
  date = {2015},
  title = {Lorem},
  yeara = {2015},
}

@book{ipsum,
  author = {Uthor, Anne},
  date = {2015-08-07},
  montha = {08},
  title = {Ipsum},
  yeara = {2015},
}

as expected.

But if I now try to overwrite year and month in biber-date.conf

<?xml version="1.0" encoding="UTF-8"?>
<config>
  <output_fieldcase>lower</output_fieldcase>
  <datamodel>
    <fields>
      <field fieldtype="field" datatype="literal">year</field>
      <field fieldtype="field" datatype="literal">month</field>
    </fields>
    <entryfields>
      <field>year</field>
      <field>month</field>
    </entryfields>
  </datamodel>
  <sourcemap>
    <maps datatype="bibtex">
      <map map_overwrite="1">
        <map_step map_field_source="date" map_match="[0-9]{4}-([0-9]{2})" map_final="1"/>
        <map_step map_field_set="montha" map_field_value="$1"/>
      </map>
      <map map_overwrite="1">
        <map_step map_field_source="date" map_match="([0-9]{4})" map_final="1"/>
        <map_step map_field_set="yeara" map_field_value="$1"/>
      </map>
    </maps>
  </sourcemap>
</config>

the output of

biber --tool --configfile=biber-date.conf augustus.bib  

is

@article{kattan_timeseries_2015,
  author = {Kattan, Ahmed and Fatima, Shaheen and Arif, Muhammad},
  date = {2015-04},
  journaltitle = {Information Sciences},
  title = {Time-series event-based prediction: An unsupervised learning framework based on genetic programming},
}

@book{lorem,
  author = {Uthor, Anne},
  date = {2015},
  title = {Lorem},
}

@book{ipsum,
  author = {Uthor, Anne},
  date = {2015-08-07},
  title = {Ipsum},
}

not quite as hoped.

Would it be possible to get the expected output here as well.

I realise that year and month are tricky beasts, but especially in the light of #275 I expected my .conf to override the existing data model and make year and month normal fields that can and will be output as usual.

[plk]

I am about to overhaul the datamodel merging code and I will check this too.

[plk]

Should be fixed in 2.15 DEV - see what you think. Bibtex ouput now checks to see if year and month are datepart fields and if not, it will try to output them as-is, unless there is also a day field as this is not a valid stand-alone field and therefore must be rolled into date.

[schoeps]

@moewew @plk I was the one complaining at https://tex.stackexchange.com/q/265895/35864, so thanks! I use the holidays to clean up my huge bib-file :)

[moewew]

Works very well in the tests I came up with. Thanks you very much.

[schoeps]

Indeed, works also for me. I am using this to make biber spit out a (legacy) bibtex-compatible bib-file. Thanks!

[LukasCBossert]

Great - but when will the version with this fix be released?

[plk]

I think we will be releasing a new version fairly soon.