Yeoman - AngularJS : karma configuration for directives testing

app myDirective.js

// file: app/scripts/directives/myDirective.js

angular.module('someApp.directive').directive('myDirective', function () {
  return {
    templateUrl: 'templates/myDirective.html',         // HERE
    ....
  }
});

karma.conf.js

// file: karma.conf.js

// Karma configuration
// http://karma-runner.github.io/0.10/config/configuration-file.html

module.exports = function (config) {
  config.set({
    basePath: '',

    frameworks: ['jasmine'],

    files: [
      'app/bower_components/angular/angular.js',
      'app/bower_components/angular-mocks/angular-mocks.js',
      'app/scripts/*.coffee',
      'app/scripts/**/*.coffee',
      'test/mock/**/*.coffee',
      'test/spec/**/*.coffee',
      'app/templates/**/*.html'         // HERE
    ],

    preprocessors: {
      '**/*.coffee': 'coffee',
      'app/templates/**/*.html': 'ng-html2js'         // HERE
    },

    ngHtml2JsPreprocessor: {
      // strip this from the file path
      stripPrefix: 'app/'         // HERE
    },

    autoWatch: true,

    ...

  });
};

test myDirective.js

// file: test/spec/directives/myDirective.js

describe('Directive: myDirective', function() {

  var element, scope;

  beforeEach(module('someApp.directive'));

  beforeEach(module('templates/myDirective.html', 'templates/myDirective.html'));   // HERE. load module prepared by ng-html2js

  beforeEach(inject(function($compile, $rootScope) {
    scope = $rootScope.$new();
    // prepare scope in which your directive should be used
    // ...
    element = angular.element('<myDirective></myDirective>');
    $compile(element)(scope);
    scope = element.scope();
    return scope.$apply();
  }));

  it('fancy-dancy test', inject(function($compile) {
    expect(element.text()).toBe('...');
  }));

});

I had to do one more step to make it work in karma.conf.js:

plugins: [
      'karma-ng-html2js-preprocessor',   // HERE
      'karma-phantomjs-launcher',
      'karma-jasmine'
    ],