git reset --hard # removes staged and working directory changes

## !! be very careful with these !!
## you may end up deleting what you don't want to
## read comments and manual.
git clean -f -d # remove untracked
git clean -f -x -d # CAUTION: as above but removes ignored files like config.
git clean -fxd :/ # CAUTION: as above, but cleans untracked and ignored files through the entire repo (without :/, the operation affects only the current directory)

要事先查看将要删除的内容，而不是实际删除它，请使用-n标志（这基本上是一个测试运行）。当您准备好实际删除时，请删除该-n标志：

git clean -nfd