ag91 / coverlay-for-scala-example

Plumbing to see code coverage in Scala files

Coverlay for Scala

This is some Elisp to show code coverage directly in your Scala files. It integrates Coverlay with a few Scala modes for Emacs.

The idea is to produce an lcov from your cobertura files, and then activate coverlay. Also we want Emacs to do the whole thing for us, so also the generation of the coverage report is done asynchronously.

Check out this blog for more details: https://ag91.github.io/blog/2021/01/11/coverlay-for-scala-or-how-to-produce-lcov-from-cobertura/

I do this for Scala, but I guess as long as you produce cobertura.xml, you can always go back to lcov by changing this code slightly (get in touch if you would like that).

Installation and Dependencies

This project depends on the following external dependencies:

• sbt-scoverage

And the following Emacs packages:

• coverlay
• async.el
• dash.el
• s.el
• projectile.el
• scala-mode.el
• esxml.el

If you use use-package and you are on a Linux system, you can try things out in a clean Emacs:

(require 'package)
(eval-and-compile
  (setq
   package-archives
   '(("melpa-stable" . "https://stable.melpa.org/packages/")
     ("melpa" . "https://melpa.org/packages/")
     ("marmalade"   . "https://marmalade-repo.org/packages/")
     ("org"         . "https://orgmode.org/elpa/")
     ("gnu"         . "https://elpa.gnu.org/packages/"))))
(package-initialize)

 ;;; Bootstrap use-package
;; Install use-package if it's not already installed.
(unless (package-installed-p 'use-package)
  (package-refresh-contents)
  (package-install 'use-package))
(setq use-package-always-ensure 't)
(require 'use-package)
(require 'bind-key)
(use-package coverlay)
(use-package async)
(use-package dash)
(use-package f)
(use-package s)
(use-package scala-mode)
(use-package esxml)
(use-package projectile)

emacs -Q -l /tmp/minimal-setup.el -l ./coverlay-for-scala.el