\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[french]{babel}
\usepackage[version=3]{acro}

\DeclareAcroArticle{definite}{\nospace}

\NewAcroCommand\dacs{m}{\acrodefinite\UseAcroTemplate{short}{#1}}
\NewAcroCommand\Dacs{m}{\acroupper\acrodefinite\UseAcroTemplate{short}{#1}}
\NewAcroCommand\dacl{m}{\acrodefinite\UseAcroTemplate{long}{#1}}
\NewAcroCommand\Dacl{m}{\acroupper\acrodefinite\UseAcroTemplate{long}{#1}}

\DeclareAcronym{hadopi}{
  short = HADOPI ,
  long = Haute Autorit\'{e} pour la diffusion des \oe uvres et la protection des
    droits sur l’Internet ,
  short-definite = l'\nospace ,
  long-definite = la ,
}

\begin{document}

\dacs{hadopi}

\Dacl{hadopi}

\end{document}
