$injector is not working in my test why?

-$injector is not working in my test why?-

Why it is not able to return my service?

foo.service.js:

'use strict';

angular.module('fooApp')
.factory('FooService', function () {

    var function1 = function function1(value) {
        return value;
    };

    return {
        function1 : function1
    };
});

my test(foo.service.spec.js)

'use strict';

describe('Service: FooService', function () {
beforeEach(module('fooApp'));

var FooService;

beforeEach(function(){
    inject(function ($injector) {
        FooService= $injector.get('FooService');
    });
});

it('should...', function(){
    expect(FooService.function1('...')).toEqual(...);
....

});

....
});

When I evaluate FooService is undefined. Why ?

Error stacktrace:

...
TypeError: 'undefined' is not an object (evaluating 'FooService.function1')
...