Right now it just shows:
M test.txt
1 file changed, 1 insertion(+), 0 deletions(-)
Previously we used git-commit-notifier to have nice colored diffs in our developer mailing list (this is a post-receive hook) when we were using Gitolite.
I could set it up the same in the Gerrit instance but then we’d be using two different mail mechanisms, email templates, and double emails on successful merges.
Sean Pearce, a developer on the project answered my question on Google Groups. He suggested plugging into the change-merged hook on your server:
http://gerrit.googlecode.com/svn/documentation/2.2.0/config-hooks.html#_change_merged
Then, as the callback use git-commit-notifier.