使用 titlesec /etoc 对齐标题

Question

请考虑以下代码：

\documentclass[a4paper,twoside,11pt]{report}
\usepackage{fontspec}
\usepackage{polyglossia}
\setmainlanguage[babelshorthands=true]{italian}
\PolyglossiaSetup{italian}{indentfirst=false}

\usepackage{titlesec}
\usepackage{etoc}

\renewcommand{\thechapter}{\scshape\roman{chapter}}
\renewcommand\thesection{\arabic{section}}

\titleformat{\chapter}[display]
  {\normalfont\fontsize{11}{12}\selectfont}
  {\scshape\thechapter}
  {0pt}
  {}
\titleformat{\section}
  {\normalfont\fontsize{11}{12}\selectfont}
  {\thesection}
  {1em}
  {}
\titleformat{\subsection}
  {\normalfont\fontsize{11}{12}\selectfont\itshape}
  {}
  {1em}
  {}

\titlespacing{\chapter}
  {0pt}{0pt}{3cm}

\etocsetstyle{chapter}
  {}
  {\addvspace{2ex}\leavevmode\leftskip 0cm\relax}
  {\ifShowPage % conditional deciding the display or not of the page number
    \llap{\makebox[1.5cm][r]{\mdseries\etocpage}\hspace{.5cm}}%
   \fi
    \normalsize\makebox[1cm][r]{\etocnumber\phantom{.}}\hspace{10pt}%
  \parbox[t]{\dimexpr\linewidth-1cm-27pt\relax}{\etocname\par}\hfill\par
  }
  {}

\etocsetstyle{section}
  {}
  {\leavevmode\leftskip 0cm\relax}
  {\llap{\makebox[1.5cm][r]{\mdseries\etocpage}\hspace{.5cm}}%
    \normalsize\makebox[1cm][r]{\etocnumber.}\hspace{10pt}%
  \parbox[t]{\dimexpr\linewidth-1cm-27pt\relax}{\etocname\par}\hfill\par
  }
  {}

\newif\ifShowPage

\begin{document}

\tableofcontents

\chapter{Chapter One}
\section{Section One}
\section{Section Two}
\section{Section Three}
\section{Section Four}

\chapter{Chapter Two}
\section{Section One}
\section{Section Two}
\section{Section Three}
\section{Section Four}

\chapter{Chapter Three}
\section{Section One}
\section{Section Two}
\section{Section Three}
\section{Section Four}

\end{document}

我不明白为什么第一章标题上有一个不想要的缩进，如图所示。如何才能将此标题与其他标题对齐？谢谢！

PS 使用 pdflatex 一切正常，但使用 xelatex 时我遇到了一点小麻烦......

Answer 1

以下结果对我来说是正确的。我将\parindent本地设置为 0pt。请注意，这并不是真正解决您问题的方法，而是一种变通方法，因为我仍然不知道问题到底是什么。

\documentclass[a4paper,twoside,11pt]{report}
\usepackage{fontspec}
\usepackage{polyglossia}
\setmainlanguage[babelshorthands=true]{italian}
\PolyglossiaSetup{italian}{indentfirst=false}

\usepackage{titlesec}
\usepackage{etoc}

\renewcommand{\thechapter}{\scshape\roman{chapter}}
\renewcommand\thesection{\arabic{section}}

\titleformat{\chapter}[display]
  {\normalfont\fontsize{11}{12}\selectfont}
  {\scshape\thechapter}
  {0pt}
  {}
\titleformat{\section}
  {\normalfont\fontsize{11}{12}\selectfont}
  {\thesection}
  {1em}
  {}
\titleformat{\subsection}
  {\normalfont\fontsize{11}{12}\selectfont\itshape}
  {}
  {1em}
  {}

\titlespacing{\chapter}
  {0pt}{0pt}{3cm}

\etocsetstyle{chapter}
  {}
  {\addvspace{2ex}\leavevmode\leftskip 0cm\relax}
  {\ifShowPage % conditional deciding the display or not of the page number
    \llap{\makebox[1.5cm][r]{\mdseries\etocpage}\hspace{.5cm}}%
   \fi
    \normalsize\makebox[1cm][r]{\etocnumber\phantom{.}}\hspace{10pt}%
  \parbox[t]{\dimexpr\linewidth-1cm-27pt\relax}{\etocname\par}\hfill\par
  }
  {}

\etocsetstyle{section}
  {}
  {\leavevmode\leftskip 0cm\relax}
  {\llap{\makebox[1.5cm][r]{\mdseries\etocpage}\hspace{.5cm}}%
    \normalsize\makebox[1cm][r]{\etocnumber.}\hspace{10pt}%
  \parbox[t]{\dimexpr\linewidth-1cm-27pt\relax}{\etocname\par}\hfill\par
  }
  {}

\newif\ifShowPage

\begin{document}

\begingroup
\parindent0pt
\tableofcontents
\endgroup

\chapter{Chapter One}
\section{Section One}
\section{Section Two}
\section{Section Three}
\section{Section Four}

\chapter{Chapter Two}
\section{Section One}
\section{Section Two}
\section{Section Three}
\section{Section Four}

\chapter{Chapter Three}
\section{Section One}
\section{Section Two}
\section{Section Three}
\section{Section Four}

\end{document}