git selective revert local changes from a file

I believe you can do it most simply with:

git checkout -p <optional filename(s)>

From the manpage:

   −p, −−patch
       Interactively select hunks in the difference between the <tree−ish>
       (or the index, if unspecified) and the working tree. The chosen
       hunks are then applied in reverse to the working tree (and if a
       <tree−ish> was specified, the index).

       This means that you can use git checkout −p to selectively discard
       edits from your current working tree.