本科毕业论文封面编译失败

[ODYYYYYY]

描述问题

直接复制 #142 中给出的代码并使用xelatex编译，结果编译器报错，同时产生的pdf文件在info的描述处生成了错误的信息（例如“导师”变成了 c__fdu_name_supervisor_tl 等等）

预期结果：

实际结果：

• 操作系统
  • Windows
  • macOS
  • Ubuntu
• TeX 发行版
  • TeX Live 2024
  • MiKTeX 23.5
• 编译方式
  • XeLaTeX
  • LuaLaTeX
• fduthesis 获取方式：
  • 发行版自带
  • 通过 GitHub Releases 下载（最新发布版本）
  • 通过 git clone 下载（开发版本）
  • 在 Overleaf 上使用
• fduthesis 版本：v0.9a

[ODYYYYYY]

Compiler显示信息如下：

This is XeTeX, Version 3.141592653-2.6-0.999996 (TeX Live 2024) (preloaded format=xelatex)
 restricted \write18 enabled.
entering extended mode
(./Test.tex
LaTeX2e <2023-11-01> patch level 1
L3 programming layer <2024-04-11>
(d:/texlive/2024/texmf-dist/tex/latex/fduthesis/fduthesis.cls
Document Class: fduthesis 2023/05/27 v0.9a Thesis template for Fudan University
(d:/texlive/2024/texmf-dist/tex/latex/l3packages/xtemplate/xtemplate.sty (d:/texlive/2024/texmf-dist/tex/latex/l3packages/xtemplate/xtemplate-2023-10-10.sty (d:/texlive/2024/texmf-dist/tex/latex/l3kernel/expl3.sty (d:/texlive/2024/texmf-dist/tex/latex/l3backend/l3backend-xetex.def)))) (d:/texlive/2024/texmf-dist/tex/latex/l3packages/l3keys2e/l3keys2e.sty) (d:/texlive/2024/texmf-dist/tex/latex/fduthesis/fduthesis.def) (d:/texlive/2024/texmf-dist/tex/latex/ctex/ctexbook.cls (d:/texlive/2024/texmf-dist/tex/latex/ctex/config/ctexbackend.cfg)
Document Class: ctexbook 2022/07/14 v2.5.10 Chinese adapter for class book (CTEX)
(d:/texlive/2024/texmf-dist/tex/latex/ctex/ctexhook.sty) (d:/texlive/2024/texmf-dist/tex/latex/ctex/ctexpatch.sty) (d:/texlive/2024/texmf-dist/tex/latex/base/fix-cm.sty (d:/texlive/2024/texmf-dist/tex/latex/base/ts1enc.def)) (d:/texlive/2024/texmf-dist/tex/latex/ctex/config/ctexopts.cfg) (d:/texlive/2024/texmf-dist/tex/latex/base/book.cls
Document Class: book 2023/05/17 v1.4n Standard LaTeX document class
(d:/texlive/2024/texmf-dist/tex/latex/base/bk12.clo)) (d:/texlive/2024/texmf-dist/tex/latex/ctex/engine/ctex-engine-xetex.def (d:/texlive/2024/texmf-dist/tex/xelatex/xecjk/xeCJK.sty (d:/texlive/2024/texmf-dist/tex/latex/fontspec/fontspec.sty (d:/texlive/2024/texmf-dist/tex/latex/l3packages/xparse/xparse.sty) (d:/texlive/2024/texmf-dist/tex/latex/fontspec/fontspec-xetex.sty (d:/texlive/2024/texmf-dist/tex/latex/base/fontenc.sty) (d:/texlive/2024/texmf-dist/tex/latex/fontspec/fontspec.cfg))) (d:/texlive/2024/texmf-dist/tex/xelatex/xecjk/xeCJK.cfg))) (d:/texlive/2024/texmf-dist/tex/latex/zhnumber/zhnumber.sty (d:/texlive/2024/texmf-dist/tex/latex/zhnumber/zhnumber-utf8.cfg)) (d:/texlive/2024/texmf-dist/tex/latex/ctex/scheme/ctex-scheme-chinese-book.def (d:/texlive/2024/texmf-dist/tex/latex/ctex/config/ctex-name-utf8.cfg)) (d:/texlive/2024/texmf-dist/tex/latex/ctex/ctex-cs4size.clo)) (d:/texlive/2024/texmf-dist/tex/latex/ctex/config/ctex.cfg) (d:/texlive/2024/texmf-dist/tex/latex/amsmath/amsmath.sty
For additional information on amsmath, use the `?' option.
(d:/texlive/2024/texmf-dist/tex/latex/amsmath/amstext.sty (d:/texlive/2024/texmf-dist/tex/latex/amsmath/amsgen.sty)) (d:/texlive/2024/texmf-dist/tex/latex/amsmath/amsbsy.sty) (d:/texlive/2024/texmf-dist/tex/latex/amsmath/amsopn.sty)) (d:/texlive/2024/texmf-dist/tex/latex/unicode-math/unicode-math.sty (d:/texlive/2024/texmf-dist/tex/latex/unicode-math/unicode-math-xetex.sty (d:/texlive/2024/texmf-dist/tex/latex/unicode-math/unicode-math-table.tex))) (d:/texlive/2024/texmf-dist/tex/latex/geometry/geometry.sty (d:/texlive/2024/texmf-dist/tex/latex/graphics/keyval.sty) (d:/texlive/2024/texmf-dist/tex/generic/iftex/ifvtex.sty (d:/texlive/2024/texmf-dist/tex/generic/iftex/iftex.sty))) (d:/texlive/2024/texmf-dist/tex/latex/fancyhdr/fancyhdr.sty) (d:/texlive/2024/texmf-dist/tex/latex/footmisc/footmisc.sty (d:/texlive/2024/texmf-dist/tex/latex/bigfoot/perpage.sty)) (d:/texlive/2024/texmf-dist/tex/latex/ntheorem/ntheorem.sty
Style `ntheorem', Version 1.33 <2011/08/15>
(d:/texlive/2024/texmf-dist/tex/latex/base/ifthen.sty)) (d:/texlive/2024/texmf-dist/tex/latex/graphics/graphicx.sty (d:/texlive/2024/texmf-dist/tex/latex/graphics/graphics.sty (d:/texlive/2024/texmf-dist/tex/latex/graphics/trig.sty) (d:/texlive/2024/texmf-dist/tex/latex/graphics-cfg/graphics.cfg) (d:/texlive/2024/texmf-dist/tex/latex/graphics-def/xetex.def))) (d:/texlive/2024/texmf-dist/tex/latex/tools/longtable.sty) (d:/texlive/2024/texmf-dist/tex/latex/caption/caption.sty (d:/texlive/2024/texmf-dist/tex/latex/caption/caption3.sty) (d:/texlive/2024/texmf-dist/tex/latex/caption/ltcaption.sty)) (d:/texlive/2024/texmf-dist/tex/latex/xcolor/xcolor.sty (d:/texlive/2024/texmf-dist/tex/latex/graphics-cfg/color.cfg) (d:/texlive/2024/texmf-dist/tex/latex/graphics/mathcolor.ltx))) (d:/texlive/2024/texmf-dist/tex/latex/hyperref/hyperref.sty (d:/texlive/2024/texmf-dist/tex/latex/kvsetkeys/kvsetkeys.sty) (d:/texlive/2024/texmf-dist/tex/generic/kvdefinekeys/kvdefinekeys.sty) (d:/texlive/2024/texmf-dist/tex/generic/pdfescape/pdfescape.sty (d:/texlive/2024/texmf-dist/tex/generic/ltxcmds/ltxcmds.sty) (d:/texlive/2024/texmf-dist/tex/generic/pdftexcmds/pdftexcmds.sty (d:/texlive/2024/texmf-dist/tex/generic/infwarerr/infwarerr.sty))) (d:/texlive/2024/texmf-dist/tex/latex/hycolor/hycolor.sty) (d:/texlive/2024/texmf-dist/tex/latex/auxhook/auxhook.sty) (d:/texlive/2024/texmf-dist/tex/latex/hyperref/nameref.sty (d:/texlive/2024/texmf-dist/tex/latex/refcount/refcount.sty) (d:/texlive/2024/texmf-dist/tex/generic/gettitlestring/gettitlestring.sty (d:/texlive/2024/texmf-dist/tex/latex/kvoptions/kvoptions.sty))) (d:/texlive/2024/texmf-dist/tex/latex/etoolbox/etoolbox.sty) (d:/texlive/2024/texmf-dist/tex/latex/hyperref/pd1enc.def) (d:/texlive/2024/texmf-dist/tex/generic/intcalc/intcalc.sty) (d:/texlive/2024/texmf-dist/tex/latex/hyperref/puenc.def) (d:/texlive/2024/texmf-dist/tex/latex/url/url.sty) (d:/texlive/2024/texmf-dist/tex/generic/bitset/bitset.sty (d:/texlive/2024/texmf-dist/tex/generic/bigintcalc/bigintcalc.sty)) (d:/texlive/2024/texmf-dist/tex/latex/base/atbegshi-ltx.sty)) (d:/texlive/2024/texmf-dist/tex/latex/hyperref/hxetex.def (d:/texlive/2024/texmf-dist/tex/generic/stringenc/stringenc.sty) (d:/texlive/2024/texmf-dist/tex/latex/rerunfilecheck/rerunfilecheck.sty (d:/texlive/2024/texmf-dist/tex/latex/base/atveryend-ltx.sty) (d:/texlive/2024/texmf-dist/tex/generic/uniquecounter/uniquecounter.sty))) (d:/texlive/2024/texmf-dist/tex/latex/hyperref/psdextra.def)

Package fontspec Warning: 
(fontspec)                Script 'CJK' not explicitly supported within font
(fontspec)                'FandolSong-Regular'. Check the typeset output, and
(fontspec)                if it is okay then ignore this warning. Otherwise a
(fontspec)                different font should be chosen.

No file Test.aux.
*geometry* driver: auto-detecting
*geometry* detected driver: xetex

Package hyperref Warning: Rerun to get /PageLabels entry.


Package fontspec Warning: 
(fontspec)                Script 'CJK' not explicitly supported within font
(fontspec)                'FandolHei-Regular'. Check the typeset output, and
(fontspec)                if it is okay then ignore this warning. Otherwise a
(fontspec)                different font should be chosen.

./Test.tex:129: Missing \endcsname inserted.
<to be read again> 
                   \hfil 
l.129 \begin{document}
                      
./Test.tex:129: Use of \??? doesn't match its definition.
<argument> \???  
                 ! LaTeX Error: Erroneous variable \csname\endcsname used!
l.129 \begin{document}
                      
./Test.tex:129: Extra \endcsname.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.129 \begin{document}
                      

Overfull \hbox (97.88063pt too wide) detected at line 129
 \TU/texgyreheros(0)/m/n/15.05624 c__fdu_name_author_tl
./Test.tex:129: Missing \endcsname inserted.
<to be read again> 
                   \hfil 
l.129 \begin{document}
                      
./Test.tex:129: Use of \??? doesn't match its definition.
<argument> \???  
                 ! LaTeX Error: Erroneous variable \csname\endcsname used!
l.129 \begin{document}
                      
./Test.tex:129: Extra \endcsname.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.129 \begin{document}
                      

Overfull \hbox (124.6657pt too wide) detected at line 129
 \TU/texgyreheros(0)/m/n/15.05624 c__fdu_name_student_id_tl
./Test.tex:129: Missing \endcsname inserted.
<to be read again> 
                   \hfil 
l.129 \begin{document}
                      
./Test.tex:129: Use of \??? doesn't match its definition.
<argument> \???  
                 ! LaTeX Error: Erroneous variable \csname\endcsname used!
l.129 \begin{document}
                      
./Test.tex:129: Extra \endcsname.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.129 \begin{document}
                      

Overfull \hbox (131.87764pt too wide) detected at line 129
 \TU/texgyreheros(0)/m/n/15.05624 c__fdu_name_department_tl
./Test.tex:129: Missing \endcsname inserted.
<to be read again> 
                   \hfil 
l.129 \begin{document}
                      
./Test.tex:129: Use of \??? doesn't match its definition.
<argument> \???  
                 ! LaTeX Error: Erroneous variable \csname\endcsname used!
l.129 \begin{document}
                      
./Test.tex:129: Extra \endcsname.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.129 \begin{document}
                      

Overfull \hbox (92.9121pt too wide) detected at line 129
 \TU/texgyreheros(0)/m/n/15.05624 c__fdu_name_major_tl
./Test.tex:129: Missing \endcsname inserted.
<to be read again> 
                   \hfil 
l.129 \begin{document}
                      
./Test.tex:129: Use of \??? doesn't match its definition.
<argument> \???  
                 ! LaTeX Error: Erroneous variable \csname\endcsname used!
l.129 \begin{document}
                      
./Test.tex:129: Extra \endcsname.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.129 \begin{document}
                      

Overfull \hbox (125.16255pt too wide) detected at line 129
 \TU/texgyreheros(0)/m/n/15.05624 c__fdu_name_supervisor_tl
./Test.tex:129: Missing \endcsname inserted.
<to be read again> 
                   \hfil 
l.129 \begin{document}
                      
./Test.tex:129: Use of \??? doesn't match its definition.
<argument> \???  
                 ! LaTeX Error: Erroneous variable \csname\endcsname used!
l.129 \begin{document}
                      
./Test.tex:129: Extra \endcsname.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.129 \begin{document}
                      

Overfull \hbox (156.96133pt too wide) detected at line 129
 \TU/texgyreheros(0)/m/n/15.05624 c__fdu_name_supervisor_title_tl
./Test.tex:129: Missing \endcsname inserted.
<to be read again> 
                   \hfil 
l.129 \begin{document}
                      
./Test.tex:129: Use of \??? doesn't match its definition.
<argument> \???  
                 ! LaTeX Error: Erroneous variable \csname\endcsname used!
l.129 \begin{document}
                      
./Test.tex:129: Extra \endcsname.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.129 \begin{document}
                      

Overfull \hbox (114.3823pt too wide) detected at line 129
 \TU/texgyreheros(0)/m/n/15.05624 c__fdu_name_affiliation_tl
./Test.tex:129: Missing \endcsname inserted.
<to be read again> 
                   \hfil 
l.129 \begin{document}
                      
./Test.tex:129: Use of \??? doesn't match its definition.
<argument> \???  
                 ! LaTeX Error: Erroneous variable \csname\endcsname used!
l.129 \begin{document}
                      
./Test.tex:129: Extra \endcsname.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.129 \begin{document}
                      

Overfull \hbox (84.34508pt too wide) detected at line 129
 \TU/texgyreheros(0)/m/n/15.05624 c__fdu_name_date_tl
[1] [2]

Package fontspec Warning: 
(fontspec)                Script 'CJK' not explicitly supported within font
(fontspec)                'FandolKai-Regular'. Check the typeset output, and
(fontspec)                if it is okay then ignore this warning. Otherwise a
(fontspec)                different font should be chosen.

[3] [4] [5] (./Test.aux)

Package rerunfilecheck Warning: File `Test.out' has changed.
(rerunfilecheck)                Rerun to get outlines right
(rerunfilecheck)                or use package `bookmark'.

 )
(see the transcript file for additional information)
Output written on Test.pdf (5 pages).
SyncTeX written on Test.synctex.gz.

Transcript written on Test.log.

[xkwxdyy]

请用把 log 内容放在 Markdown 的代码块里。

```latex
content
```

直接复制issue142中给出的代码并使用xelatex编译

建议下次这种引用要给链接，如果是同一个项目的 issue，直接用 #，比如 #142 ，会产生链接

[ODYYYYYY]

请用把 log 内容放在 Markdown 的代码块里。

```latex
content

> 直接复制issue142中给出的代码并使用xelatex编译

建议下次这种引用要给链接，如果是同一个项目的 issue，直接用 `#`，比如 #142 ，会产生链接

感谢赐教，已经进行了相应的修改！

[xkwxdyy]

建议你把 #142 那个里面的提问删掉，这里引用了之后那个下方会有提示的。

一个解决办法是把 45 和 84 行的 \__fdu_spread_box:nn 改为 \makebox 的 s 选项方案即可

% line 41
\group_begin:
  \cs_set_protected:Npn \__fdu_cover_info_aux_ii:nnnn ##1##2##3##4
    {
      \__fdu_cover_info_format:
      % \__fdu_spread_box:nn { 4 \ccwd } {##2}
      \makebox [ 4 \ccwd ] [ s ] { ##2 }
      ##4
      \__fdu_fixed_width_center_box:nn { ##1 \ccwd } {##3}
    }
  \__fdu_cover_info_aux_i:nn {  20 } { date }
\group_end:

% line 81
\cs_set_protected:Npn \__fdu_cover_info_aux_ii:nnnn #1#2#3#4
  {
    \__fdu_cover_info_format:
    % \__fdu_spread_box:nn { 4 \ccwd } {#2}
    \makebox [ 4 \ccwd ] [ s ] { #2 }
    #4
    \hbox_overlap_right:n { \__fdu_blank_underline:n { #1 \ccwd } }
    \__fdu_fixed_width_center_box:nn { #1 \ccwd } {#3}
  }

[xkwxdyy]

问题出在

\cs_set_protected:Npn \__fdu_cover_info_aux_i:nn #1#2
  {
    \__fdu_cover_info_aux_ii:nnnn {#1}
      { \tl_use:c { c__fdu_name_ #2 _tl } }
      { \tl_use:c { l__fdu_info_ #2 _tl } }
      { \c__fdu_fwid_colon_tl }
  }

\__fdu_cover_info_aux_ii:nnnn 的第二个参数需要展开。而 interface3.pdf 中可以查到 \tl_use:c 是完全可展的，且在 1.2 节可查到

Fully expandable functions Some functions are fully expandable, which allows them to be used within an x-type or e-type argument (in plain TEX terms, inside an \edef or \expanded), as well as within an f-type argument. These fully expandable functions are indicated in the documentation by a star

说明需要用 x 或者 e 或者 f 来展开，fduthesis.cls 里提供了 o 的变体

fduthesis/source/fduthesis.dtx

Line 4695 in d84e0dd

\cs_generate_variant:Nn \@@_spread_box:nn { no }

但这里改成 o 会有

! Use of \__tl_map_function_end:w doesn't match its definition.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.130 \begin{document}
                      
? 

的报错。只需要在 #142 提供的代码里面增加一行

\cs_generate_variant:Nn \__fdu_spread_box:nn { nx }

其中 x 可以改为 e 或 f，然后把两处 \__fdu_spread_box:nn 改为 \__fdu_spread_box:nx （ e 和 f 同理）即可

[ODYYYYYY]

__fdu_spread_box:nn

我直接采用了这种方案，在 \ExplSyntaxOn后直接添加了\cs_generate_variant:Nn \__fdu_spread_box:nn { ne}并将两个"nn"修改为了"ne"，xelatex编译成功且产生PDF文件无错误，感谢！！！

[ODYYYYYY]

问题出在

\cs_set_protected:Npn \__fdu_cover_info_aux_i:nn #1#2
  {
    \__fdu_cover_info_aux_ii:nnnn {#1}
      { \tl_use:c { c__fdu_name_ #2 _tl } }
      { \tl_use:c { l__fdu_info_ #2 _tl } }
      { \c__fdu_fwid_colon_tl }
  }

\__fdu_cover_info_aux_ii:nnnn 的第二个参数需要展开。而 interface3.pdf 中可以查到 \tl_use:c 是完全可展的，且在 1.2 节可查到

Fully expandable functions Some functions are fully expandable, which allows them to be used within an x-type or e-type argument (in plain TEX terms, inside an \edef or \expanded), as well as within an f-type argument. These fully expandable functions are indicated in the documentation by a star

说明需要用 x 或者 e 或者 f 来展开，fduthesis.cls 里提供了 o 的变体

fduthesis/source/fduthesis.dtx

Line 4695 in d84e0dd

\cs_generate_variant:Nn \@@_spread_box:nn { no }

但这里改成 o 会有

! Use of \__tl_map_function_end:w doesn't match its definition.
\exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: 
                                                  
l.130 \begin{document}
                      
? 

的报错。只需要在 #142 提供的代码里面增加一行

\cs_generate_variant:Nn \__fdu_spread_box:nn { nx }

其中 x 可以改为 e 或 f，然后把两处 \__fdu_spread_box:nn 改为 \__fdu_spread_box:nx （ e 和 f 同理）即可

还有一个小问题，能否把PDF封面info项后面的下划线给去掉，就像“完成日期”那一栏一样没有下划线？我的方案是将

\hbox_overlap_right:n { \__fdu_blank_underline:n { #1 \ccwd } }

注释掉。但是这么做的话会显得info名称和info对应内容纵向对不齐的情况比较明显（虽然这个对不齐在有underline时已经存在），见下图

[xkwxdyy]

为什么要去掉下划线呢，是最新规范？请提供依据

[ODYYYYYY]

为什么要去掉下划线呢，是最新规范？请提供依据

附件1：微电子学院关于本科毕业论文（设计）工作的若干规定.pdf
详见微电子学院提供的封面（PDF文件第10页-附件1（封面一））

[xkwxdyy]

这个信息是空着的，不能说明一定没下划线，你有认识上一届毕业的学长学姐吗，或者问问你的论文指导老师？先确定一下是否需要去掉下划线

[ODYYYYYY]

好的，感谢，我再去确认一下，那请问关于info名称和info内容对不齐的问题有办法解决吗？

[ODYYYYYY]

这个信息是空着的，不能说明一定没下划线，你有认识上一届毕业的学长学姐吗，或者问问你的论文指导老师？先确定一下是否需要去掉下划线

这是我找到的上一届微电子学院一位学长的本科毕业论文PDF文件的封面，可以看到是没有下划线的。

[xkwxdyy]

改了一下，你用下面的代码吧：

\documentclass{fduthesis}

% 请不要改动 \ExplSyntaxOn ... \ExplSyntaxOff 之间的代码！
\ExplSyntaxOn
\RenewDocumentCommand \makecoveri { }
  {
    \thispagestyle { empty }
    \UseInstance { fdu / cover } { cover-bachelor-default }
  }
\DeclareCoverTemplate { cover-bachelor } { logo-i, title, logo-ii, info }
\DeclareInstance { fdu / cover } { cover-bachelor-default } { cover-bachelor }
  {
    top-skip              = 0 pt plus 0.1 fill,
    bottom-skip           = 0 pt plus 0.4 fill,
    logo-i  / content     = \__fdu_cover_logo_i:,
    title   / content     = \c__fdu_name_thesis_title_tl,
    logo-ii / content     = \__fdu_cover_logo_ii:,
    info    / content     = \__fdu_cover_info:,
    title   / format      = \fontsize { 35 } { 35 } \selectfont \sffamily,
    title   / bottom-skip = 0 pt plus 0.1 fill,
    logo-ii / bottom-skip = 0 pt plus 0.2 fill,
    logo-i  / align       = center,
    title   / align       = center,
    logo-ii / align       = center,
    info    / align       = center,
  }
\cs_set_protected:Npn \__fdu_cover_logo_i:
  { \includegraphics [ width = 6.60 cm ] { \l__fdu_logo_name_tl   } }
\cs_set_protected:Npn \__fdu_cover_logo_ii:
  { \includegraphics [ width = 3.70 cm ] { \l__fdu_logo_emblem_tl } }
\cs_set_protected:Npn \__fdu_cover_info:
  {
    \__fdu_cover_title:n       {  20 }
    \__fdu_cover_info_aux_i:nn { 7.5 } { author           }
    \__fdu_cover_info_aux_i:nn { 7.5 } { student_id       } \__fdu_cover_info_skip:
    \__fdu_cover_info_aux_i:nn {  20 } { department       } \__fdu_cover_info_skip:
    \__fdu_cover_info_aux_i:nn {  20 } { major            } \__fdu_cover_info_skip:
    \__fdu_cover_info_aux_i:nn { 7.5 } { supervisor       }
    \__fdu_cover_info_aux_i:nn { 7.5 } { supervisor_title } \__fdu_cover_info_skip:
    \__fdu_cover_info_aux_i:nn {  20 } { affiliation      } \__fdu_cover_info_skip:
    \group_begin:
      \cs_set_protected:Npn \__fdu_cover_info_aux_ii:nnnn ##1##2##3##4
        {
          \__fdu_cover_info_format:
          \__fdu_spread_box:nx { 4 \ccwd } {##2}
          ##4
          \__fdu_fixed_width_center_box:nn { ##1 \ccwd } {##3}
        }
      \__fdu_cover_info_aux_i:nn {  20 } { date }
    \group_end:
  }
\cs_set_protected:Npn \__fdu_cover_title:n #1
  {
    \exp_args:NNV \clist_set:Nn \l__fdu_tmpa_clist \l__fdu_info_title_tl
    \clist_pop:NN  \l__fdu_tmpa_clist \l__fdu_tmpa_tl
    \clist_pop:NNF \l__fdu_tmpa_clist \l__fdu_tmpb_tl
      { \tl_set_eq:NN \l__fdu_tmpb_tl \c_empty_tl }
    \__fdu_cover_info_aux_ii:nnnn {#1}
      { \c__fdu_name_title_tl } { \l__fdu_tmpa_tl } { \c__fdu_fwid_colon_tl }
    \__fdu_cover_info_skip:
    \__fdu_cover_info_aux_ii:nnnn {#1}
      { } { \l__fdu_tmpb_tl } { \phantom { \c__fdu_fwid_colon_tl } }
    \__fdu_cover_info_skip:
  }
\cs_set_protected:Npn \__fdu_cover_info_aux_i:nn #1#2
  {
    \__fdu_cover_info_aux_ii:nnnn {#1}
      { \tl_use:c { c__fdu_name_ #2 _tl } }
      { \tl_use:c { l__fdu_info_ #2 _tl } }
      { \c__fdu_fwid_colon_tl }
  }
\cs_generate_variant:Nn \__fdu_spread_box:nn { nx }
\cs_set_protected:Npn \__fdu_cover_info_aux_ii:nnnn #1#2#3#4
  {
    \__fdu_cover_info_format:
    \__fdu_spread_box:nx { 4 \ccwd } {#2}
    #4
    \__fdu_fixed_width_left_box:nn { #1 \ccwd } {#3}
  }
\cs_new_protected:Npn \__fdu_fixed_width_left_box:nn #1#2
  { \parbox [t] {#1} { \raggedright #2 } }
\cs_set_protected:Npn \__fdu_cover_info_format:
  { \zihao { -3 } \sffamily }
\cs_set_protected:Npn \__fdu_cover_info_skip:
  { \skip_vertical:n { 0.2 ex } }
\cs_set_protected:Npn \__fdu_define_name:nn #1#2
  { \tl_set:cn { c__fdu_name_ #1 _tl } {#2} }
\keys_define:nn { fdu / info }
  {
    affiliation      .tl_set:N = \l__fdu_info_affiliation_tl,
    supervisor-title .tl_set:N = \l__fdu_info_supervisor_title_tl,
  }
\clist_map_inline:nn
  {
    { student_id       } { 学号         },
    { thesis_title     } { 本科毕业论文 },
    { title            } { 论文题目     },
    { supervisor       } { 指导教师     },
    { supervisor_title } { 职称         },
    { affiliation      } { 单位         },
  }
  { \__fdu_define_name:nn #1 }
\tl_set:Nn \l__fdu_logo_name_tl   { fudan-name.pdf   }
\tl_set:Nn \l__fdu_logo_emblem_tl { fudan-emblem-new.pdf }
\ExplSyntaxOff

% 这里开始就和原来一样了
\fdusetup{
  info={
    % 以下各项都要填写，否则会报错
    author           = {张三},
    student-id       = {18110000000},
    department       = {计算机学院},
    major            = {计算机},
    title            = {题目第一行,第二行},
    % title            = {题目只有第一行},
    supervisor       = {李四五},
    supervisor-title = {教授},
    affiliation      = {软件学院},
  }
}

\begin{document}
...
\end{document}

[xkwxdyy]

里面关于标题的代码我也改了一下，标题只有一行的时候也保留了间距：

[xkwxdyy]

不过你发的规范里面日期竟然还是居中的（上面也保留了这个居中），看上去怪怪的