Separate biblatex biblios, descending numbering, 'check' filters

Question

I would like to produce multiple bibliographies in a CV, separating papers that have no dates from those with dates (one way to tell if they are 'under review' or 'published' - I realise there are other ways to do this, such as keywords etc.). The same for conference papers.

With the changes to biblatex, my old code no longer works. I managed to make some progress using the solution here, ie, I do have separate bibliographies for journals papers and conferences with descending numbering, if I don't filter the empty-date entries.

I am filtering the entries produced by \printbibligraphy using 'check', which works, but is not compatible with the counters used for the descending numbering (ie, it does not exclude the 'filtered' papers).

How do I go about modifying the code below to fix the counters?

Thank you in advance!

\documentclass[10pt, a4paper]{article}
\usepackage[czech,english]{babel}  
\usepackage[backend=biber,style=ieee,defernumbers=true,sorting=keysort]{biblatex}


%%%%%%%%%%%%
% From https://tex.stackexchange.com/questions/367163/separate-biblatex-bibliographies-with-newest-entry-and-highest-reference-number:
% does not work correctly due to 'check' in bibliographies...

% Count total number of entries in each refsection
\AtDataInput{%
  \ifcsundef{bbx@processedentries:\therefsection}
    {\csgdef{bbx@processedentries:\therefsection}{}}
    {}%
  \xifinlistcs{\thefield{entrykey}}{bbx@processedentries:\therefsection}{}{%
    \listcsxadd{bbx@processedentries:\therefsection}{\thefield{entrykey}}%
    \csnumgdef{bbx@entrycount:\therefsection:\thefield{entrytype}}{%
      \csuse{bbx@entrycount:\therefsection:\thefield{entrytype}}+1}}}

% Print the labelnumber as the total number of entries in the
% current refsection, minus the actual labelnumber, plus one
\DeclareFieldFormat{labelnumber}{\mkbibdesc{#1}}    
\newrobustcmd*{\mkbibdesc}[1]{%
  \number\numexpr\csuse{bbx@entrycount:\therefsection:\thefield{entrytype}}+1-#1\relax}

%%%%%%%%%%%%
\DeclareSortingScheme{keysort}{
\sort[direction=descending]{\field{entrykey}  }
}

\addbibresource{pubs1.bib}
\addbibresource{pubs2.bib}

\begin{document}

\defbibcheck{confnoyear}{ \ifentrytype{inproceedings} {\iffieldundef{year}{}{\skipentry}} {\skipentry} }
\defbibcheck{journoyear}{ \ifentrytype{article}       {\iffieldundef{year}{}{\skipentry}} {\skipentry} }
\defbibcheck{confwyear}{  \ifentrytype{inproceedings} {\iffieldundef{year}{\skipentry}{}} {\skipentry} }
\defbibcheck{jourwyear}{  \ifentrytype{article}       {\iffieldundef{year}{\skipentry}{}} {\skipentry} }

% Journal papers under review (w/out years)
\newrefcontext[labelprefix=JS,sorting=keysort]
\printbibliography[check=journoyear]   \nocite{*}

% Journals published
\newrefcontext[labelprefix=J,sorting=keysort]
\printbibliography[check=jourwyear] \nocite{*}

% Conf papers under review (w/out years)
\newrefcontext[labelprefix=CS,sorting=keysort]
\printbibliography[check=confnoyear] \nocite{*}

% Conf papers published 
\newrefcontext[labelprefix=C,sorting=keysort]
\printbibliography[check=confwyear] \nocite{*}


\end{document}

Answer 1

This answer was written in 2018 and may no longer work as intended on newer systems. Refer to Reverse numbering in biblatex with customized bibchecks for an answer that works with biblatex v3.16 (2020-12-31).

The answer to Separate Biblatex bibliographies with newest entry and highest reference number at the top and Audrey's answer to Multibib reverse label or sort order, from which it derives, count the numbers of items in each refsection and then calculate the backwards label number from that. As you rightfully point out, your bibchecks skip over several entries that are still part of the refsection, so this approach leads to discontinuous numbering.

Here is a completely different approach. A solution for you set-up must be based on the specific bibliography environment since we need to count the maximum number of items in each bibliography environment to be able to count backwards in each bibliography.

For each bibliography environment we count the number of items in the list and write it to the .aux file so it is available at the beginning of the list in the next run. Then if the number of items is available at the beginning of the list, we recalculate the labelnumber based on the maximum number of items in the current bibliography. Finally that new labelnumber must be registered as the official labelnumber of the current item.

\documentclass[10pt, a4paper]{article}
\usepackage[czech,english]{babel}  
\usepackage[backend=biber,style=ieee,defernumbers=true,sorting=keysort]{biblatex}
\makeatletter
\newcounter{bibenvcounter}
\newcounter{bibitemcounter}[bibenvcounter]
\newcommand*{\auxkacz@envmax}[2]{%
  \csgdef{blxkacz@envmax@#1}{#2}}
\defbibenvironment{bibliography}
  {\stepcounter{bibenvcounter}%
   \list
     {\ifcsundef{blxkacz@envmax@\the\value{bibenvcounter}}
        {}
        {\numdef\abx@field@localnumber{%
           \csuse{blxkacz@envmax@\the\value{bibenvcounter}}%
             -\value{bibitemcounter}}%
         \csundef{blx@defer@\the\c@refsection
            @\blx@refcontext@context
            @\abx@field@entrykey}%
         \blx@thelabelnumber}%
      \stepcounter{bibitemcounter}%
      \printtext[labelnumberwidth]{%
        \printfield{labelprefix}%
        \printfield{labelnumber}}}
     {\setlength{\labelwidth}{\labelnumberwidth}%
      \setlength{\leftmargin}{\labelwidth}%
      \setlength{\labelsep}{\biblabelsep}%
      \addtolength{\leftmargin}{\labelsep}%
      \setlength{\itemsep}{\bibitemsep}%
      \setlength{\parsep}{\bibparsep}}%
      \renewcommand*{\makelabel}[1]{\hss##1}}
  {\endlist
   \blx@auxwrite@mainaux{}{%
     \string\auxkacz@envmax
       {\the\value{bibenvcounter}}
       {\the\value{bibitemcounter}}}}
  {\item}
\makeatother
\defbibcheck{confnoyear}{ \ifentrytype{inproceedings} {\iffieldundef{year}{}{\skipentry}} {\skipentry} }
\defbibcheck{journoyear}{ \ifentrytype{article}       {\iffieldundef{year}{}{\skipentry}} {\skipentry} }
\defbibcheck{confwyear}{  \ifentrytype{inproceedings} {\iffieldundef{year}{\skipentry}{}} {\skipentry} }
\defbibcheck{jourwyear}{  \ifentrytype{article}       {\iffieldundef{year}{\skipentry}{}} {\skipentry} }
\DeclareSortingScheme{keysort}{
  \sort[direction=descending]{\field{entrykey}}
}
\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@inproceedings{a,
  author  = {Author, A.},
  title   = {A Title},
  date    = {1980},
}
@inproceedings{b,
  author  = {Buthor, B.},
  title   = {B Title},
  date    = {1980},
}
@inproceedings{c,
  author  = {Buthor, C.},
  title   = {C Title},
  date    = {1980},
}
@inproceedings{d,
  author  = {Duthor, D.},
  title   = {A Title},
}
@inproceedings{e,
  author  = {Euthor, E.},
  title   = {B Title},
}
\end{filecontents}
\addbibresource{\jobname.bib}
\begin{document}
\newrefcontext[labelprefix=CS,sorting=keysort]
\printbibliography[check=confnoyear] \nocite{*}
\newrefcontext[labelprefix=C,sorting=keysort]
\printbibliography[check=confwyear] \nocite{*}
\end{document}