AngularJS Jasmine Factory test

I'm trying to test a Factory with Jasmine but I'm getting:

Error: [$injector:unpr] Unknown provider: Provider <- <- RecaptchaFactory

Here is my factory:

(function() {
'use strict';

angular
    .module('app')
    .factory('RecaptchaFactory', Recaptcha);

Recaptcha.$inject = [''];

function Recaptcha() {
    return {
        passwordAttempts: passwordAttempts,
    };

    var passwordAttempts = 0;

}   
})();

And my test:

describe("RecaptchaFactory", function(){
beforeEach(module("app"));

var factory;

beforeEach(inject(function(RecaptchaFactory){
   factory = RecaptchaFactory;
}));

describe("init", function(){
    it("should init passwordAttempts with 0", function(){
        expect(factory.passwordAttempts).toBe(0);
    });
});
});