git gui diff/merge tool

Download and Install P4V

Download the free Perforce Visual Client dmg from here. Once it’s downloaded, copy p4merge from the disk image to your /Applications directory.

Write some simple shell scripts

p4merge*

Create a new text file in /usr/local/bin called p4merge and add the following lines:

#!/bin/sh
/Applications/p4merge.app/Contents/MacOS/p4merge $*

Make the script executable by entering this command:

chmod +x p4merge

p4diff*

Create a new text file in /usr/local/bin called p4diff and add the following lines:

#!/bin/sh
[ $# -eq 7 ] && /usr/local/bin/p4merge "$2" "$5"

Make the script executable by entering this command:

chmod +x p4diff

Configure Git to use the scripts

Open your git configuration file (probably ~/.gitconig) and add these lines:

[merge]
	keepBackup = false;
	tool = p4merge
[mergetool "p4merge"]
	cmd = p4merge "$BASE" "$LOCAL" "$REMOTE" "$MERGED"
        prompt = false
        keepTemporaries = false
	trustExitCode = false
	keepBackup = false
[diff]
	external = p4diff