更新到 Fontspec 19/01 v2.6L 的最新版本后，出现以下错误
))
! Undefined control sequence.
\__fontspec_init_ttc:n #1->\str_if_eq:eeT
{\str_lower_case:f {\l__fontspec_e...
l.5 \setmainfont{Minion Pro}
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.
平均能量损失
\documentclass{article}
\usepackage{lipsum}
\usepackage{fontspec}
\setmainfont{Minion Pro}
\begin{document}
\lipsum
\end{document}
第一个错误的完整日志：
This is LuaTeX, Version 1.09.0 (MiKTeX 2.9.6930 64-bit) (format=lualatex 2019.1.25) 25 JAN 2019 10:32
restricted system commands enabled.
**Test.tex
(./Test.tex
LaTeX2e <2018-12-01>
Lua module: luaotfload-main 2018-12-19 2.94 luaotfload entry point
Lua module: luaotfload-init 2018-12-19 2.94 luaotfload submodule / initializatio
n
Lua module: lualibs 2018-12-19 2.62 ConTeXt Lua standard libraries.
Lua module: lualibs-extended 2018-12-19 2.62 ConTeXt Lua libraries -- extended c
ollection.
Lua module: luaotfload-log 2018-12-19 2.94 luaotfload submodule / logging
Lua module: luaotfload-parsers 2018-12-19 2.94 luaotfload submodule / filelist
Lua module: luaotfload-configuration 2018-12-19 2.94 luaotfload submodule / conf
ig file reader
luaotfload | conf : Root cache directory is C:/Users/Sony Vaio/AppData/Local/MiK
TeX/2.9/luatex-cache/generic/names.
luaotfload | init : Loading fontloader “fontloader-2018-12-19.lua” from kpse
-resolved path “C:/Users/Sony Vaio/AppData/Local/Programs/MiKTeX 2.9/tex/luate
x/luaotfload/fontloader-2018-12-19.lua”.
Lua-only attribute luaotfload@state = 1
Lua-only attribute luaotfload@noligature = 2
Lua-only attribute luaotfload@syllabe = 3
luaotfload | init : Context OpenType loader version “3.107”
Inserting `luaotfload.node_processor' at position 1 in `pre_linebreak_filter'.
Inserting `luaotfload.node_processor' at position 1 in `hpack_filter'.
Lua module: luaotfload-loaders 2018-12-19 2.94 luaotfload submodule / callback h
andling
Inserting `luaotfload.define_font' at position 1 in `define_font'.
Lua module: luaotfload-database 2018-12-19 2.94 luaotfload submodule / database
Lua module: luaotfload-colors 2018-12-19 2.94 luaotfload submodule / color
Lua-only attribute luaotfload_color_attribute = 4
Lua module: luaotfload-resolvers 2018-12-19 2.94 luaotfload submodule / resolver
s
luaotfload | conf : Root cache directory is C:/Users/Sony Vaio/AppData/Local/MiK
TeX/2.9/luatex-cache/generic/names.
Lua module: luaotfload-features 2018-12-19 2.94 luaotfload submodule / features
Lua module: luaotfload-letterspace 2018-12-19 2.94 luaotfload submodule / color
Lua module: luaotfload-auxiliary 2018-12-19 2.94 luaotfload submodule / auxiliar
y functions
Inserting `luaotfload.aux.set_sscale_dimens' at position 1 in `luaotfload.patch_
font'.
Inserting `luaotfload.aux.patch_cambria_domh' at position 2 in `luaotfload.patch
_font'.
Inserting `luaotfload.aux.fixup_fontdata' at position 1 in `luaotfload.patch_fon
t_unsafe'.
Inserting `luaotfload.aux.set_capheight' at position 3 in `luaotfload.patch_font
'.
Inserting `luaotfload.rewrite_fontname' at position 4 in `luaotfload.patch_font'
.
luaotfload | main : initialization completed in 1.504 seconds
("C:/Users/Sony Vaio/AppData/Local/Programs/MiKTeX 2.9/tex/latex/base/article.c
ls"
Document Class: article 2018/09/03 v1.4i Standard LaTeX document class
("C:/Users/Sony Vaio/AppData/Local/Programs/MiKTeX 2.9/tex/latex/base/size10.cl
o"
File: size10.clo 2018/09/03 v1.4i Standard LaTeX file (size option)
luaotfload | db : Font names database loaded from C:/Users/Sony Vaio/AppData/Loc
al/MiKTeX/2.9/luatex-cache/generic/names/luaotfload-names.luc)
\c@part=\count80
\c@section=\count81
\c@subsection=\count82
\c@subsubsection=\count83
\c@paragraph=\count84
\c@subparagraph=\count85
\c@figure=\count86
\c@table=\count87
\abovecaptionskip=\skip41
\belowcaptionskip=\skip42
\bibindent=\dimen102
) ("C:/Users/Sony Vaio/AppData/Roaming/MiKTeX/2.9/tex/latex/lipsum/lipsum.sty"
Package: lipsum 2014/07/27 v1.3 150 paragraphs of Lorem Ipsum dummy text
\c@lips@count=\count88
)
("C:/Users/Sony Vaio/AppData/Local/Programs/MiKTeX 2.9/tex/latex/fontspec/fonts
pec.sty"
("C:/Users/Sony Vaio/AppData/Roaming/MiKTeX/2.9/tex/latex/l3packages/xparse/xpa
rse.sty"
("C:/Users/Sony Vaio/AppData/Roaming/MiKTeX/2.9/tex/latex/l3kernel/expl3.sty"
Package: expl3 2017/07/15 L3 programming layer (loader)
("C:/Users/Sony Vaio/AppData/Roaming/MiKTeX/2.9/tex/latex/l3kernel/expl3-code.t
ex"
Package: expl3 2017/07/15 L3 programming layer (code)