SourceTree: how to do a git diff in the opposite direction?

This is not possible in SourceTree.

I asked this question here on answers.atlassian.com and found out from an Atlassian employee that the ability to do a diff in the opposite direction is not available, that a diff between commits is always shown in "forward history" order.

Some alternatives:

1. Use a different external GUI diff viewer

   
   -or-

2. Copy the files from older commit 1111 into the working tree for newer commit 3333, and then see the diffs in the working tree, e.g.,

$ cd {repo}
$ git diff --name-only 3333..1111 > /tmp/list_of_files_changed
$ git checkout 1111
$ mkdir /tmp/files_changed
$ cp --parents -pr $(cat /tmp/list_of_files_changed) /tmp/files_changed 
$ git checkout 3333
$ cp -pr /tmp/files_changed/* .
# (now look at the diff in SourceTree for the working copy)

Supposing you need to diff a specific branch from your current branch, the only way is the Berik answer because is not possible to inform branch as second argument.

So this show diff normal order:

git diff branch_abc Makefile

and this show diff on reverse order:

git diff -R branch_abc Makefile