I used to use Diffmerge for my merge/comparison needs, however I find the outdated interface to be unfriendly and ugly to look at.

On Windows I use Sourcetree and Beyond Compare works without integration, it shows up in the appropriate dropdowns but on Mac it does not. I don’t understand why Sourcetree on Mac is different to Windows, but anyway.

SourceTree for Mac 2.0.5 contains an updated hgsubversion extension, but you may still have to follow the below steps to get it working. If the second step's command doesn't work and you're on Yosemite, see the following links: https://github.com/Homebrew/homebrew/issues/35744. Sourcetree, a free visual Git client for Mac, comes with its own bundled version of Git. You can download Sourcetree here. To learn how to use Git with Sourcetree (and how to host your Git repositories on Bitbucket) you can follow our comprehensive Git tutorial with Bitbucket and Sourcetree.

Brew Uninstall Sourcetree

Fortunately, Sourcetree makes it easy to use third party comparison tools even if they are not in the dropdowns.

Firstly, we need to install Beyond Compare “Command Line Tools” which allows us to call Beyond Compare.

Brew Source Code Pro

Go into the Beyond Compare menu and choose Install Command Line Tools.

Secondly we need to configure Sourcetree to use the command line for Beyond Compare:

In Preferences and then the “Diff” tab, at the bottom there is a section which allows you to specify the compare tool.