force git mergetool to amend a previously done merge

Question

I use DiffMerge for 3-way merges in git. I just completed a mandatory merge job but realized I missed something out and would like to remerge and use the same 3-way GUI functionality. When I tried:

git mergetool my/path/file.ext

I got

No files need merging

How can I force mergetool to be able to do a 3-way merge in a GUI again rather than saving the remote under a different name and fishing out for deltas?

Answer 1

You can try and reset the file to its pre-merged state, as mentioned in "Git merging: Restart conflict resolution in a single file":

git checkout -m -- your/File

And then relaunch git mergetool.

That supposes you didn't completed the merge and made a commit.