Git - Changes made in meld (as the difftool) not saved

Question

I followed Jörg W Mittag's answer in this post and have configured meld as the difftool in my git. Now I can view and compare differences of a file in different branches perfectly with this command:

git checkout branch1
git difftool branch1:file.f90 branch2:file.f90

I executed the above command, made and saved changes in meld. However, when I check the file using:

emacs file.f90

The changes I made earlier in meld are not saved at all. I don't understand why this is so; I must have not entirely correctly configured meld as the diff tool. Could any one help me with this problem? Thanks!!

Answer 1

Because you have explicitly given the branches of both files to be diff'ed, meld is working on temporary copies of both files. Try just giving the name of the non-checked out branch:file; this should cause meld to compare a temporary copy of the given branch:file with the checked out file of the same name.

Answer 2

To avoid the need to specify the filename twice, use the following:

git difftool branch -- file

This will compare branch:file with file in the working tree.

Furthermore, to diff the entire working tree with branch, use:

git difftool --dir-diff branch

As mentioned in other answers, if you need to diff branch with other_branch (some branch different from what is currently checked out), you must first check out other_branch before using the above commands.