Error while executing karma tests

When i tried to execute some tests using this command line, i get many errors :
Running "karma:unit" (karma) task                                                                              
19 08 2015 13:03:07.905:WARN [watcher]: Pattern "C:/ng/firstngapp/test/mock/**/*.js" does not match any file.  
19 08 2015 13:03:08.628:INFO [karma]: Karma v0.13.9 server started at http://localhost:8080/                   
19 08 2015 13:03:08.721:INFO [launcher]: Starting browser PhantomJS                                            
19 08 2015 13:03:11.550:INFO [PhantomJS 1.9.8 (Windows 7 0.0.0)]: Connected on socket CrW_D9jEniUIsLIKAAAA with
 id 40933185                                                                                                   
PhantomJS 1.9.8 (Windows 7 0.0.0) ERROR                                                                        
  ReferenceError: Can't find variable: require                                                                 
  at C:/ng/firstngapp/bower_components/uglify-js/uglify-js.js:14                                               

Warning: Task "karma:unit" failed. Use --force to continue.                                                    

Aborted due to warnings.                                                                                       

Execution Time (2015-08-19 13:02:34 UTC)                                                                       
wiredep:app         6s  ████████████ 15%                                                                       
concurrent:test  24.4s  ████████████████████████████████████████████████ 63%                                   
connect:test      1.4s  ███ 4%                                                                                 
karma:unit        6.3s  █████████████ 16%                                                                      
Total 38.8s
thank's for any help
karma-runner / grunt-karma

Error while executing karma tests #160
