can not pass the test and generate dist folder

[edison-ymc]

From what I understand from Gruntfile, it will auto run test and then build after I issue grunt under project root. However, it stops after test and it never goes build. I got the error message like following. I wonder what doest the warning(Warning: Task "karma:unit" failed. Use --force to continue.) mean?

Running "karma:unit" (karma) task
INFO [karma]: Karma v0.10.10 server started at http://localhost:8080/
INFO [launcher]: Starting browser PhantomJS
INFO [PhantomJS 1.9.7 (Mac OS X)]: Connected on socket dGc_L2nzI5wAH4cOGYrV
PhantomJS 1.9.7 (Mac OS X): Executed 0 of 0 ERROR (0.204 secs / 0 secs)
Warning: Task "karma:unit" failed. Use --force to continue.

Aborted due to warnings.

[edison-ymc]

my karam.conf.js file looks like

module.exports = function(config) {
config.set({
autoWatch: true,
basePath: '..',
frameworks: ['jasmine'],
files: [
'app/bower_components/jquery/dist/jquery.js',
'app/bower_components/angular/angular.js',
'app/bower_components/angular-mocks/angular-mocks.js',
'app/bower_components/angular-resource/angular-resource.js',
'app/bower_components/angular-cookies/angular-cookies.js',
'app/bower_components/angular-sanitize/angular-sanitize.js',
'app/bower_components/angular-route/angular-route.js',
'app/scripts/.js',
'app/scripts/__/.js',
'test/client/spec/*/.js'
],
exclude: [],
port: 8080,
browsers: [
'PhantomJS'
],
plugins: [
'karma-phantomjs-launcher',
'karma-jasmine'
],
singleRun: false,
colors: true,
logLevel: config.LOG_INFO,
});
};