Karma-coverage not found: But, it is installed

Question

I used this guide http://karma-runner.github.io/0.8/config/coverage.html to setup my Karma-coverage plugin. Furthermore, it gets installed locally via the package.json file, which looks like this:

{
    "name": "myApp",
    "version": "0.1.0",
    "devDependencies": {
        "karma-jasmine": "latest",
        "karma-coverage": "latest",
        "karma-coffee-preprocessor": "latest",
        "karma-chrome-launcher": "latest",
        "coffee-script": "latest"
    }
}

My Karma.conf looks like this:

// Karma configuration
// Generated on Sun Dec 07 2014 15:51:07 GMT+0100 (CET)

module.exports = function(config) {
  config.set({

    // base path that will be used to resolve all patterns (eg. files, exclude)
    basePath: '',


    // frameworks to use
    // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
    frameworks: ['jasmine'],

    // list of files / patterns to load in the browser
    files: [
        'javascripts/vendor/jquery_211.js',
        'javascripts/vendor/angular.js',
        'javascripts/vendor/angular-route.js',
        'javascripts/vendor/angular-mocks.js',
        '../app/assets/javascripts/app.coffee',
        'javascripts/*.js',
        'test/controllers/*.js'
    ],


    // list of files to exclude
    exclude: [
    ],


    // preprocess matching files before serving them to the browser
    // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
    preprocessors: {
        '../app/assets/javascripts/app.coffee' : ['coffee'],
        '**/javascripts/*.js': 'coverage'
        //'**/*.coffee': ['coffee']
    },


    // test results reporter to use
    // possible values: 'dots', 'progress'
    // available reporters: https://npmjs.org/browse/keyword/karma-reporter
    reporters: ['progress', 'coverage'],

    // web server port
    port: 9876,


    // enable / disable colors in the output (reporters and logs)
    colors: true,


    // level of logging
    // possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
    logLevel: config.LOG_INFO,


    // enable / disable watching file and executing tests whenever any file changes
    autoWatch: true,


    // start these browsers
    // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
    browsers: ['Chrome'],


    // Continuous Integration mode
    // if true, Karma captures browsers, runs the tests and exits
    singleRun: false
  });
};

Now, while running karma I receive the error

WARN [reporter]: Can not load "coverage", it is not registered!
  Perhaps you are missing some plugin?
INFO [karma]: Karma v0.12.28 server started at http://localhost:9876/
INFO [launcher]: Starting browser Chrome
WARN [preprocess]: Can not load "coverage", it is not registered!
  Perhaps you are missing some plugin?

It does not matter, if I include karma-coverage in the plugin section of the karma.conf file, the problem stays the same (since the plugin gets loaded locally, I should not need the plugin part anyway...). I hope somebody of you guys has an idea... Thank you!

Answer 1

The solution for this problem was that I had a couple of installed node_modules within my users home folder. After deinstalling these modules and the locally installed ones via npm, I made a clean reinstall via npm link. This solved the problem for me!