See: http://www.tcrayford.net/2009/12/08/Lein-Autotest.html
I’ve been doing a lot of testing for a clojure side project recently, and got envious of Ruby people having nice tools. In particular I liked the coloured output and automatic test running from rspactor.
I found watchr and came up with this script, which simply watches for changes to .clj files in /src and /test and runs lein test in the shell window.
To get started, install watchr
gem install watchr
and run the script in the home directory for your Leiningen-backed clojure project.
watchr /path/to/script
The script also does some (very basic) red/green colouring of outputs using zsh color codes.