Git diff tool on every commit?

Question

I would like to run git difftool HEAD~3.. path/to/file and have git open the difftool for each of those three commits so that I can see a side-by-side view of each commit.

How would I go about getting git-difftool to do that?

Answer 1

This would accomplish what you describe:

git difftool HEAD~3 HEAD~2 path/to/file
git difftool HEAD~2 HEAD~1 path/to/file
git difftool HEAD~1 HEAD path/to/file

Want to automate this process? Is it always three commits? Do you want a three-way merge?

Update:

If the answers are yes-yes-no, the solution will be:

for i in {3..1}; do
  git difftool HEAD~$i HEAD~$((i-1)) path/to/file
done

Update:

If the answers are yes-no-yes, it is essentially what @ruffin asks here. See my answer there.

Answer 2

Or you could just run git log -p - it does pretty much the same thing that you want

Answer 3

UPDATE:

Matthieu Moy suggested much better variant:

for rev in $(git rev-list <committish>.. ); do
    git difftool ${rev} ${rev}~1;
    done

The OLD version of the answer:

I would say you do something like:

git rev-list <commitish>.. | wc -l

or

git log --oneline <commitish>.. | wc -l

This will calculate how many revision you have between your <commitish> and HEAD.

Then using this number you can automatically run through the commits to see the diffs

c=`git log --online <commitish>.. | wc -l`

while ! ${c} eq 0 ; do

git difftool HEAD~${c} HEAD~${($c-1)}
c=${c}-1
done

Answer 4

for i in 1 2 3
do
  ((j=${i}-1))
  git difftool HEAD~${i}..HEAD~${j} path/to/file &
done

Answer 5

A slightly different approach:

1) Perform an interactive rebase

git rebase -i <commitish>

2) Mark all your commits for edit

3) For each commit run

git difftool HEAD~1

4) Go to the next commit and repeat step 3

git rebase --continue

The added advantage is that if you see a problem in the review, you have already checked out the commit that you want to fix.