"every path" style affects \node "path" when decorating

Question

Here's a MWE:

\documentclass{standalone}

\usepackage{tikz}
\usetikzlibrary{decorations.pathmorphing}

\begin{document}
\begin{tikzpicture}
  \draw[decorate, decoration=random steps] (0,0) -- (10,0);
  \node[decorate, decoration=random steps, draw, fill=yellow, inner sep=0.5cm] at (5,-2) {};
\end{tikzpicture}
\end{document}

For a more complex picture, I wanted to apply the same decoration to all lines and nodes, and so I used "every path":

\documentclass{standalone}

\usepackage{tikz}
\usetikzlibrary{decorations.pathmorphing}

\begin{document}
\begin{tikzpicture}[every path/.style={decorate, decoration=random steps}]
  \draw (0,0) -- (10,0);
  \node[draw, fill=yellow, inner sep=0.5cm] at (5,-2) {};
\end{tikzpicture}
\end{document}

However, this results in an error: "I cannot decorate an empty path". I think I understand what the problem is: \node ... is replaced with \path node ... and we thus have an empty path.

But how can I achieve what I want, namely applying the same decoration to all lines AND nodes (let's assume there a lots of them) without having to specify it explicitly for each \draw and \node command?

Answer 1

This problem has been solved some time ago by Jake, I think, in this stellar answer. It is sort of the opposite of what you suggest: if you use \path (<coordinates>) node..., it works.

\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{decorations.pathmorphing}
\begin{document}
\begin{tikzpicture}[every path/.style={decorate,decoration=random steps}]
  \draw (0,0) -- (10,0);
  \path (5,-2) node[decorate,draw, fill=yellow, inner sep=0.5cm]  {};
\end{tikzpicture}
\end{document}

EDIT: The picture looks a bit as if the left edge of the node was straight. However, that's just an accident, as can be seen from the following animation in which the random seed varies.

\documentclass[tikz,border=3.14mm]{standalone}
\usetikzlibrary{decorations.pathmorphing}
\begin{document}
\foreach \X in {1,...,50}
{\begin{tikzpicture}[every path/.style={decorate,decoration=random steps}]
  \pgfmathsetseed{\X}   
  \draw (0,0) -- (10,0);
  \path (5,-2) node[decorate,draw, fill=yellow, inner sep=0.5cm]  {};
\end{tikzpicture}}
\end{document}

EDIT: And if you don't want to write draw,decorate over and over, you could just append this to the node styles.

\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{decorations.pathmorphing}
\begin{document}
\begin{tikzpicture}[every path/.style={decorate,decoration=random steps},
every node/.append style={draw,decorate}]
  \draw (0,0) -- (10,0);
  \path (5,-2) node[fill=yellow, inner sep=0.5cm]  {};
\end{tikzpicture}
\end{document}

Answer 2

apparently every path doesn't work as you expected. you still need to explicit say, which lines, shapes has decorate path:

\documentclass{standalone}

\usepackage{tikz}
\usetikzlibrary{decorations.pathmorphing}

\begin{document}
\begin{tikzpicture}[every path/.style={decoration=random steps}]
  \draw[decorate] (0,0) -- (10,0);
  \node[decorate, draw, fill=yellow, inner sep=0.5cm] at (5,-2) {};
\end{tikzpicture}
\end{document}

so, it maybe more handy (for shorter writing) to define path style for example as

DP/.style={%decorated path
           decorate, decoration=random steps}

and than use as follows:

\documentclass[tikz, margin=3mm]{standalone}
\usetikzlibrary{decorations.pathmorphing}

\begin{document}
\begin{tikzpicture}[DP/.style={%decorated path
                                decorate, decoration=random steps}]
  \draw[DP] (0,0) -- (10,0);
  \node[DP, draw, fill=yellow, inner sep=0.5cm] at (5,-2) {};
\end{tikzpicture}
\end{document}