Git tool to remove lines from staging if they consist only of changes in whitespace

Question

The point in removing trailing whitespace is that if everyone does it always then you end up with a diff that is minimal, ie. it consists only of code changes and not whitespace

Answer 1

I'd been using a script based on @GregBacon's answer for years, but at some point git changed the output of git diff -b so that the whitespace changes it didn't show as changes were included in the patch context lines in the after state rather than the before state.

I found if I reversed the clean diff and the corresponding apply, the script would work again.

So my complete script used to look like this:

#!/bin/bash

clean=`git diff --cached -b`
git apply --cached <(git diff --cached -R)
echo "$clean" | git apply --cached -
clean=

And now looks like:

#!/bin/bash

clean=`git diff --cached -b -R`
git apply --cached <(git diff --cached -R)
echo "$clean" | git apply --cached -R -
clean=

I also have a script to leave only whitespace changes in a commit. This is useful if while you fix something you make some whitespace fixes elsewhere in the file, and you want to commit the whitespace fixes first in a separate commit. It is just:

git apply --cached -R <(git diff --cached -w)