Macro based flags for forest tree

Question

I'm using simple y/n macros as flags in my document to include or exclude certain parts of the overall document (these normally are in a separate "config.tex" file for ease of use). With the forest package, I get strange results when using this approach (using pdftex). The inserted texts seem to be interpreted as text instead of added or non-added leaves.

What am I doing wrong? Thanks in advance for your help.

Minimum working example:

\documentclass[]{scrreprt}

\usepackage{ifthen}
\usepackage[edges]{forest}

\newcommand{\AddIf}[3]{\ifthenelse{\equal{#1}{y}}{#2}{#3}}

\newcommand{\hasOptionOne}{y}
\newcommand{\hasOptionFour}{y}

\begin{document}

The user has the following options:
\begin{itemize}
    \AddIf{\hasOptionOne}{\item Option One}{}
    \item Option Two
    \item Option Three
    \AddIf{\hasOptionFour}{\item Option Four}{}
\end{itemize}

\begin{figure}
    \centering
    \caption{Available Options}
    \label{fig-available-options}
    \begin{forest}
        for tree={draw,align=center},
        forked edges,
        [Main item
            \AddIf{\hasOptionOne}{[Option One]}{}
            [Option Two]
            [Option Three]
            \AddIf{\hasOptionFour}{[Option Four]}{}
        ]
    \end{forest}
\end{figure}

\end{document}

Result:

Answer 1

Since you asked for it... I replaced your command \AddIf by some version that can be appropriately expanded. And then a trick is used that has also some applications in pgfplots and so on. It makes sure that the content of the tree gets expanded first, and then it gets passed to forest.

\documentclass[]{scrreprt}

% \usepackage{ifthen} % no longer used here
\usepackage[edges]{forest}
\newcommand{\Yes}{y}
\newcommand{\AddIf}[3]{\ifx#1\Yes%
#2%
\else
#3%
\fi}

\newcommand{\hasOptionOne}{y}
\newcommand{\hasOptionFour}{y}

\begin{document}

The user has the following options:
\begin{itemize}
    \AddIf{\hasOptionOne}{\item Option One}{}
    \item Option Two
    \item Option Three
    \AddIf{\hasOptionFour}{\item Option Four}{}
\end{itemize}

\begin{figure}
    \centering
    \caption{Available Options}
    \label{fig-available-options}
    \edef\temp{\noexpand\begin{forest}
        for tree={draw,align=center},
        forked edges,
        [Main item
            \AddIf{\hasOptionOne}{[Option One]}{}
            [Option Two]
            [Option Three]
            \AddIf{\hasOptionFour}{[Option Four]}{}
        ]
    \noexpand\end{forest}}
    \temp
\end{figure}

\end{document}