Adding a dot in chapter's name without cross-referencing problems

Question

I would like to add a dot after the number of each section (including chapters) in a report class document. I'd prefer not to have to resort to Koma-script solutions. There are a lot of other good ideas here: How to add a dot after the section number? but either they don't take care of the problem that cross-referencing comes with a dot as well, or they include only sections and below and not chapters. My Latex knowledge is too limited to generalize Mico's solution by myself, but it should be straightforward (seriously this question should be a comment to these posts, but I'm not allowed to comment :) ).

Alternatively, one could use the fix proposed here: Remove dot-after-number in figure captions while keeping the dot in chapter/section captions with label/ref instead of figure... So see, I'm pretty close but still missing something!

Answer 1

\documentclass{report}

\usepackage{etoolbox}
\makeatletter
\patchcmd\@makechapterhead{\thechapter}{\thechapter.}{}{\fail}
\patchcmd\@seccntformat{\csname the#1\endcsname}{\csname the#1\endcsname.}{}{\fail}
\makeatother
\begin{document}
\chapter{chapter}\label{chap}
\section{section}\label{sec}
\ref{chap}, \ref{sec}
\end{document}