bibliography-specific formatting of multiple book entries for same author

Question

I have a book with multiple bibliographies. My editor wants a special formatting for one of the bibliographies. Below is an MWE and below the MWE the explanation:

MWE:

\documentclass[]{book}


\usepackage[style=authortitle-dw,
edsuper=true,
namefont=smallcaps,
useprefix=true,
ibidemfont=smallcaps,
idemfont=smallcaps,
idembibformat=dash,
shorthandibid=true,
backref=false,
backrefstyle=none,
hyperref=true,
isbn=false,
backend=biber,
citereset=chapter,
edstringincitations=false,
bibencoding=utf8]{biblatex}

\usepackage{filecontents}

\begin{filecontents}{quellen.bib}
@incollection{inproc1,
    Author = {Test Author},
    crossref = {proc},
    Pages = {1--10},
    Title = {Testing the Title}}

@incollection{inproc2,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the second Title}}
@incollection{inproc4,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the third Title}}
@incollection{inproc5,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the forth Title}}
@incollection{inproc6,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the fifth Title}}
@collection{proc,
    Editor = {Senor Editor and Senora Editora},
    Publisher = {Any Publisher},
    Title = {My Proceedings},
    Year = {2013},
    shorttitle = {Shorttitle}}

@inproceedings{inproc3,
    Author  = {Nother Author},
    Publisher = {Nother Publisher},
    Title   = {In Some Other Proceedings},
    Maintitle = {Main Title of Other Proceedings},
    Year     = {2001},
}
\end{filecontents}

\begin{filecontents}{literatur.bib}
    @incollection{inproc12,
        Author = {Test Author},
        crossref = {proc},
        Pages = {1--10},
        Title = {Testing the Title}}

    @incollection{inproc22,
        Author = {Test Author},
        crossref = {proc},
        Pages = {10--20},
        Title = {Testing the second Title}}

    @incollection{inproc42,
        Author = {Test Author},
        crossref = {proc},
        Pages = {10--20},
        Title = {Testing the third Title}}

    @incollection{inproc52,
        Author = {Test Author},
        crossref = {proc},
        Pages = {10--20},
        Title = {Testing the forth Title}}

    @incollection{inproc62,
        Author = {Test Author},
        crossref = {proc},
        Pages = {10--20},
        Title = {Testing the fifth Title}}

    @collection{proc2,
        Editor = {Senor Editor and Senora Editora},
        Publisher = {Any Publisher},
        Title = {My Proceedings},
        Year = {2013},
        shorttitle = {Shorttitle}}

    @inproceedings{inproc32,
        Author  = {Nother Author},
        Publisher = {Nother Publisher},
        Title   = {In Some Other Proceedings},
        Maintitle = {Main Title of Other Proceedings},
        Year     = {2001},
    }
\end{filecontents}

\addbibresource{literatur.bib}
\addbibresource{quellen.bib}

\pagestyle{empty}
\begin{document}
\cite{inproc42}\cite{inproc52}\cite{inproc62}
Test \cite{inproc12} and \cite{inproc22} and \cite{inproc32}
\cite{inproc4}\cite{inproc5}\cite{inproc6}
Test \cite{inproc1} and \cite{inproc2} and \cite{inproc3}
\printbibliography[keyword=literatur,title=Specially formatted bibliography]
\printbibliography[keyword=quellen,title=Plain old'n sturdy bibliography]
\end{document}

And my biber.conf looks like

<?xml version="1.0" encoding="UTF-8"?>
<config>
<sourcemap>
  <maps datatype="bibtex" bmap_overwrite="1">
    <map>
      <per_datasource>literatur.bib</per_datasource>
      <map_step map_field_set="KEYWORDS" map_field_value="literatur"/>
    </map>
    <map>
      <per_datasource>quellen.bib</per_datasource>
      <map_step map_field_set="KEYWORDS" map_field_value="quellen"/>
    </map>        
  </maps>
</sourcemap>
</config>

The Specially formatted bibliography looks currently like this:

The first entry of the list for one author should also appear in the same formatting as the second, third..., i.e. it should start in the line below the author and have a dash in front of it

Author, Test:
  - Testing the fifth title ...
  - Testing the forth title ...

Answer 1

Wow. I can't believe this actually works...

Here's a possible way forward.

Set the biblatex option minxrefs=2 (hopefully you are not already using this).

We use a complicated set of source maps for the heavy lifting. We set keywords based on the bib file. We create a new entry of type specialauthor containing just the author and keyword field for every entry type in literatur.bib. We set xref to point to this new entry for every item in literatur.bib.

We create a new driver to handle the entries of type specialauthor.

We turn off the printing of the editor and translator strings when printing \bibnamedash in the special bibliography.

It's not thoroughly tested, so I'd be careful. And it will definitely give odd results if you are using custom name strings. But at least it doesn't require you to make any changes to your bib data.

And putting it all together:

\documentclass{article}

\usepackage[style=authortitle-dw,
edsuper=true,
namefont=smallcaps,
useprefix=true,
ibidemfont=smallcaps,
idemfont=smallcaps,
idembibformat=dash,
shorthandibid=true,
backref=false,
backrefstyle=none,
isbn=false,
backend=biber,
edstringincitations=false,
bibencoding=utf8,
minxrefs=2]{biblatex}

\usepackage{filecontents}

\begin{filecontents}{quellen.bib}
@incollection{inproc1,
    Author = {Test Author},
    crossref = {proc},
    Pages = {1--10},
    Title = {Testing the Title}}

@incollection{inproc2,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the second Title}}
@incollection{inproc4,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the third Title}}
@incollection{inproc5,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the forth Title}}
@incollection{inproc6,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the fifth Title}}
@collection{proc,
    Editor = {Senor Editor and Senora Editora},
    Publisher = {Any Publisher},
    Title = {My Proceedings},
    Year = {2013},
    shorttitle = {Shorttitle}}

@inproceedings{inproc3,
    Author  = {Nother Author},
    Publisher = {Nother Publisher},
    Title   = {In Some Other Proceedings},
    Maintitle = {Main Title of Other Proceedings},
    Year     = {2001},
}
\end{filecontents}

\begin{filecontents}{literatur.bib}
@incollection{inproc12,
    Author = {Test Author},
    crossref = {proc},
    Pages = {1--10},
    Title = {Testing the Title}}

@incollection{inproc22,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the second Title}}

@incollection{inproc42,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the third Title}}

@incollection{inproc52,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the forth Title}}

@incollection{inproc62,
    Author = {Test Author},
    crossref = {proc},
    Pages = {10--20},
    Title = {Testing the fifth Title}}

@collection{proc2,
    Editor = {Editor, Senor and Editora, Senora},
    Publisher = {Any Publisher},
    Title = {My Proceedings},
    Year = {2013},
    shorttitle = {Shorttitle}}

@collection{proc3,
    Editor = {Editor, Senor and Editora, Senora},
    Publisher = {Any Publisher},
    Title = {Your Proceedings},
    Year = {2013},
    shorttitle = {Shorttitle}}

@inproceedings{inproc32,
    Author  = {Nother Author},
    Publisher = {Nother Publisher},
    Title   = {In Some Other Proceedings},
    Maintitle = {Main Title of Other Proceedings},
    Year     = {2001},
}
\end{filecontents}

\addbibresource{literatur.bib}
\addbibresource{quellen.bib}

\DeclareSourcemap{
  \maps[datatype=bibtex]{
    \map{
      \perdatasource{quellen.bib}
      \step[fieldset=keywords, fieldvalue={quellen}]
    }
    \map{
      \perdatasource{literatur.bib}
      \step[fieldset=keywords, fieldvalue={literatur}]
      \step[fieldset=options, fieldvalue={,}, append]
      \step[fieldsource=options, notmatch=\regexp{.*useauthor\s*=\s*false.*}, final]
      \step[fieldsource=author, match=\regexp{(.*)}, final]
      \step[entrynew={$1}, entrynewtype=specialauthor]
      \step[entrytarget={$1}, fieldset={author}, fieldvalue={$1}]
      \step[entrytarget={$1}, fieldset={keywords}, fieldvalue={literatur}]
      \step[fieldset=xref, fieldvalue={$1}]
    }
    \map{
      \perdatasource{literatur.bib}
      \step[notfield=author, final]
      \step[fieldset=options, fieldvalue={,}, append]
      \step[fieldsource=options, notmatch=\regexp{.*useeditor\s*=\s*false.*}, final]
      \step[fieldsource=editor, match=\regexp{(.*)}, final]
      \step[entrynew={$1}, entrynewtype=specialauthor]
      \step[entrytarget={$1}, fieldset={editor}, fieldvalue={$1}]
      \step[entrytarget={$1}, fieldset={keywords}, fieldvalue={literatur}]
      \step[fieldset=xref, fieldvalue={$1}]
    }
    \map{
      \perdatasource{literatur.bib}
      \step[notfield=author, final]
      \step[notfield=editor, final]
      \step[fieldset=options, fieldvalue={,}, append]
      \step[fieldsource=options, notmatch=\regexp{.*usetranslator\s*=\s*false.*}, final]
      \step[fieldsource=options, match=\regexp{.*usetranslator.*}, final]
      \step[fieldsource=translator, match=\regexp{(.*)}, final]
      \step[entrynew={$1}, entrynewtype=specialauthor]
      \step[entrytarget={$1}, fieldset={translator}, fieldvalue={$1}]
      \step[entrytarget={$1}, fieldset={options}, fieldvalue={usetranslator=true}]
      \step[entrytarget={$1}, fieldset={keywords}, fieldvalue={literatur}]
      \step[fieldset=xref, fieldvalue={$1}]
    }
  }
}

\DeclareBibliographyDriver{specialauthor}{%
  \renewcommand*{\finentrypunct}{\addcolon}%
  \ifbool{cbx:idemfull}
    {}
    {\usebibmacro{author/editor+others/translator+others}%
     \ifnameundef{labelname}
       {}
       {\setunit{\labelnamepunct}\newblock}}%
  \usebibmacro{finentry}}

\makeatletter
\AtEveryBibitem{%
  \ifboolexpr{
    test {\ifkeyword{literatur}}
    and
    not test {\ifentrytype{specialauthor}}
    and
    test {\iffieldequals{namehash}{\bbx@lasthash}}
    and
    not test {\iffirstonpage}
  }
    {\renewbibmacro*{translator+othersstrg}{}%
     \renewbibmacro*{editor+othersstrg}{}}
    {}}
\makeatother

\pagestyle{empty}
\begin{document}
\cite{inproc42}\cite{inproc52}\cite{inproc62}
Test \cite{inproc12} and \cite{inproc22} and \cite{inproc32}
\cite{inproc4}\cite{inproc5}\cite{inproc6}
Test \cite{inproc1} and \cite{inproc2} and \cite{inproc3}
\cite{proc2,proc3}
\printbibliography[keyword=literatur,title=Specially formatted bibliography]
\printbibliography[keyword=quellen,title=Plain old'n sturdy bibliography]
\end{document}