最近在研究Treemap图，但是无法安装？请教是出现什么问题呢？

> install_github("wilkox/ggfittext")
Downloading GitHub repo wilkox/ggfittext@master
from URL https://api.github.com/repos/wilkox/ggfittext/zipball/master
Installing ggfittext
"C:/PROGRA~1/R/R-33~1.2/bin/x64/R" --no-site-file --no-environ --no-save --no-restore --quiet CMD INSTALL "C:/Users/Kres/AppData/Local/Temp/RtmpEFIein/devtools683c3d27a4/wilkox-ggfittext-d3646e4" --library="C:/Users/Kres/Documents/R/win-library/3.3" --install-tests

* installing *source* package 'ggfittext' ...
** R
Error in parse(outFile) : 句法分析器157行里不能有多字节字符
ERROR: unable to collate and parse R files for package 'ggfittext'
* removing 'C:/Users/Kres/Documents/R/win-library/3.3/ggfittext'