After a merge failed with some conflicts I can list those with git diff,
but git difftool won't display them with the difftool set in the config(in my case Kaleidoscope), instead it will just use normal diff.
A git difftool comparing with a previous commit will work.
Is there a way to use git difftool on merge conflicts?
Greets Jan
Try git mergetool.
Firstly try:
git difftool -t <yourtool>
If that doesn't work, look at man git-difftool and check the list of supported tools. Check if one of those does what you want, if it does then you've narrowed it down to git not supporting Kaleidoscope, which may need some other config tweaking.
来源：https://stackoverflow.com/questions/3741931/how-to-use-git-difftool-to-diff-merge-conflicts