Trying to get APA work gives Undefined control sequence [duplicate]

Question

I'm trying to get APA working with special characters. I got kind of far with it but it gives me Undefined control sequence on rendering citations.

My minimal source is:

\documentclass[british]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}

\usepackage{csquotes}

\usepackage[czech,british]{babel}

\usepackage[backend=biber,date=short,maxcitenames=2,style=apa]{biblatex}
\addbibresource{sample.bib}
\DeclareLanguageMapping{british}{british-apa}


\begin{document}
  \cite{test}
  \nocite{*}
  \printbibliography
\end{document}

My sample.bib now looks like. It's encoded with UTF8 for sure

@book{test,
    Author = {šýř čžá and íéě č},
    Title = {šýř},
}

The error is Undefined control sequence \datecircaprint \mkbibdateapalongextra. The encoding is not the issue here I believe.

Answer 1

The writing of fddd.bib by LaTeX's environment filecontents gets broken after \usepackage[utf8]{inputenc}. Workarounds:

• Move it before:

  \begin{filecontents}{fddd.bib}
  @book{test,
      Author = {ě+íéíáý řščžčřý},
      Title = {ščřž},
  }
  \end{filecontents}
  
  \usepackage[utf8]{inputenc}
  \usepackage[T1]{fontenc}
  

• Or use package filecontents, but caution, it always overwrites the files to be generated:

  \usepackage{filecontents}% or \RequirePackage{filecontents} before `\documentclass`
  \begin{filecontents}{fddd.bib}
  @book{test,
      Author = {ě+íéíáý řščžčřý},
      Title = {ščřž},
  }
  \end{filecontents}
  

LaTeX's filecontents only uses verbatim mode via \dospecials. Special characters like backslash, hash, ... are written verbatim, but the 8-bit characters are not touched. In the example of the question, they are active by \usepackage[utf8]{inputenc} and after \usepackage[T1]{fontenc}, they are written as characters with encoding T1.

Package filecontents, however, also sanitizes the 8-bit characters. Thus the entries in UTF-8 are not changed, when written to the .bib file.

One issue remains that I get an undefined error because of \mkbibdateapalongextra, but I have not checked, that I am using the latest versions.