Git difftool not opening sometimes

Question

I have 2 folders (with different code) with git initialized. But when I do

git difftool -t meld 

one repo is working fine and asking me if I want to open files in meld to compare. The other one just output everything in the console and didn't execute meld.

Also both .git/config file is the same (except for the url)

Does anyone know why is that?

Answer 1

You may have configured your diff.tool locally instead of globally (inspect the content of .git/config files in both your porjects, and your global ~/.gitconfig file).

To set meld as your global difftool :

git config --global diff.tool meld

Answer 2

Is it possible you have configured difftool, but not mergetool, and had a conflict outstanding?

I found similar behaviour, when I had an existing conflict that needed resolving. I think what happened to me was that git was trying to be 'helpful' and launch mergetool when I asked for difftool. I had not set up any mergetool, only difftool. When I manually resolved the conflict with git add, difftool started working again. Very frustrating.

Answer 3

Meld will not launch if you are trying to check differences between two git branches, but there are no any actual code differences between them.

If this happened to you, just switch to another branch and try again, or make a small change of code and then try again.

Hope this saves someone's time.

Answer 4

If in one repository you're in conflicted state (check by git status), you need to use mergetool instead, e.g.

git mergetool -t meld

Related: git difftool runs git diff.