I am starting to put together some code for an emacs module that peers into Devel::Cover reports along the same lines as rcov-overlay.el, but also linking in linum-mode.el instead of highlighting the code lines themselves. I will need to port rcov-overlay.el, and also add a Devel::Cover formatting module to output the JSON used by the rcov-overlay module.
in reply to Coverage tool visibility within emacs
Sounds interesting but I didn't understand a word... Please, could you explain your goal in simple words avoiding to link to a lot of obscure lisp references?