I am sure you've been in situation where you made significant changes to file but want to discard them. You could always delete and clone repository again but what if you have other files that you don't want to discard that won't work. Also, you could delete file and copy paste from repository. But there is better way. You just need to checkout file. Checkout will get file from HEAD and override uncommitted changes.
git checkout fileName
If file name collides with one of branches in your repository, add
-- between checkout and file name.