How to integrate Karma with SlimerJS for testing ES6 code? - slimerjs

Question

I'm trying to integrate SlimerJS with Karma to be able to test ECMAScript 6 and AngularJS code.
When I tested ES6 code directly with SlimerJS it loads the version 0.10.2 that I installed and its works for my ES6 code.
My Firefox installed is version 50.1.0 and it works correctly with the SlimerJS when I call it directly through SlimerJS. My SLIMERJSLAUNCHER variable has been configured correctly as the SlimerJS documentation indicates to do.
But I need test AngularJS and ES6 code, so I need Karma, but don't found a way to integrate SlimerJS with Karma.
I tryed to use karma-slimerjs-launcher, but it is loading an older version of both Firefox and SlimerJS.
When I call Karma the karma-slimerjs-launcher is running Firefox 38 and SlimerJS 0.9.6 and so I lose support for ECMAScript 6.
There is a way to make karma-slimerjs-launcher call the versions of Firefox and SlimerJS that I have installed on my system instead of calling those "embedded" versions that it seems to bring?
Or there is a better way to integrate Karma and SlimerJS without karma-slimerjs-launcher?
Thanks.

Answer 1

I discovered the answer to the problem.
Instead of using the launcher that comes with outdated versions it is possible to simply start karma normally without any browser.
Just enter:
karma start
Then it is possible to start the SlimerJS headless with the command:
Xvfb-run ./slimerjs myscript.js
In the JS script we point the navigation to the karma server:
window.location.href = 'http://localhost:9876/';
Once the SlimerJS enters the Karma server the tests start to run.
The disadvantage of this method is that it takes two terminal windows to run the tests, so I did a little script in Python to solve this and serve as a launcher:
#!/usr/bin/env python3
import subprocess
import time
karma = ''
slimerjs = ''
while True:
try:
if not karma:
# Load a Karma server
print('\nKarma is loading...\n')
karma = subprocess.Popen('./karma start', shell=True)
# delays for 2 seconds for waiting Karma server
time.sleep(2)
# Load a headless SlimerJS that points to Karma server
slimerjs = subprocess.Popen(
'xvfb-run slimerjs slimerjs-cfg.js > slimerjs.log', shell=True)
print('\nSlimerJS is running...\n')
except KeyboardInterrupt:
karma.kill()
print('\n\nKarma is stopped...\n')
slimerjs.kill()
print('\nSlimerJS is stopped...\n')
break
With this to start the karma together with the slimerJS in a single console window just type:
./karma-run.py
If someone else has the same problem integrating karma with slimerjs to test ES6 this was my solution.