How do I setup DiffMerge with msysgit / gitk?

Question

I've just started using Git and it's possible I've missed something obvious, but here goes:

• I'm using msysgit 1.6.2.2 on Windows XP
• While installing, I picked option 1 to "Use Git Bash only"

I'm trying to put together a wrapper script that I can use to replace the built in git diff with DiffMerge. Based on this thread on SO, I created the following batch file:

@echo off
REM ---- Switch forward slashes to back slashes ----
set oldW=%2
set oldW=%oldW:/=\%
set newW=%5
set newW=%newW:/=\%

REM ---- Launch DiffMerge ----
"C:/Programs/SourceGear/DiffMerge/DiffMerge.exe" /title1="Old Version" %oldW% /title2="New Version" %newW%

I placed the bat file under %GIT_INSTALL%/cmd and edited my .gitconfig file as follows:

[diff]
external = C:/Programs/git/cmd/git-diff-wrapper.bat

If i launch Git Bash and execute git diff HEAD HEAD~ -- myfile

I get a message File (\dev\null) not found - which given I'm on Windows is not surprising.

Pressing on, I launched gitk and under Edit>Preferences, I chose the same wrapper script. Trying the "external diff" option for a particular file gives the cryptic error message Unknown Option "

Clearly, I have no idea what I'm doing anymore so any help would be much appreciated.

Answer 1

I looked all over the internet for the answer to this. I tried all of the solutions above and elsewhere. I could get the merge part to work and not the diff part or vice versa. So what I did eventually was to hack together my own simple solution from all the info I got on the internet which works for me. It does not require any scripts only that you edit your .gitconfig which normally resides in the following directory C:\Documents and Settings\[username] You'll need to have DiffMerge program installed already.

Here is relevant extract of my .gitconfig file. You'll just need to edit the path to where your version of of DiffMerge is. Note that I used the old DOS 8.3 format in the path

[diff]
    tool = diffm
[difftool "diffm"]
    cmd = "H:/PROGRA~1/SourceGear/DiffMerge/DiffMerge.exe $LOCAL $REMOTE"
    prompt = false

[merge]
    tool = diffmerge
[mergetool "diffmerge"]
    cmd = "H:/PROGRA~1/SourceGear/DiffMerge/DiffMerge.exe --merge --result=$MERGED $LOCAL $BASE $REMOTE" 
    trustExitCode = false
    keepBackup = false

You can also set it up using the commands git config --replace --global [options] if you so wish.

---

This simple solution works perfectly for me, too. For more recent versions of DiffMerge (3.3.1), the command path needs to be changed:

    cmd = "C:/PROGRA~1/SourceGear/Common/DiffMerge/sgdm.exe ...etc..."