Fixture service for angular unit test

fixture-app.js

'use strict';

angular.module('fixtureApp', []);

angular.module('fixtureApp')
  .service('Fixtures', function($http, $q) {
    var BASE_URL = ('/base/test/fixtures/');
    var fixtures = {};

    return {
      // Returns a promise getting the fixture on demand.
      get: function(filename) {
        var deferred = $q.defer();
        $http.get(BASE_URL + filename).success(function(data) {
          deferred.resolve(data);
        }).error(function(data, status) {
          deferred.reject({
            fixture: filename,
            message: data,
            status: status
          });
          throw new Error('Cannot get fixture ' + filename + ' ' + status + ' ' + data );
        });
        return deferred.promise;
      },
      // Retrieves the necessary fixtures.
      prefetch: function() {
        var promises = [];
        _(fixtures).each(function(promise, filename){
          promises.push(promise);
          promise.then(function(data) {
            fixtures[filename] = data;
          });
        }, this);
        return $q.all(promises);
      },
      // Wraps the get call within a function to be used to configure
      // ngMock $httpBackend.
      // prefetch need to be called before fixture is consumed.
      wrappedGet: function(filename) {
        fixtures[filename] = this.get(filename);
        return function() {
          return [200, fixtures[filename]];
        }.bind(this);
      },
      // Removes all the cached fixtures
      clear: function() {
        fixtures = {};
      }
    };
  });

var injector = angular.injector(['ng','fixtureApp']);
window.Fixtures = injector.get('Fixtures');

You don't need your own deferred objects here. $http returns promises for you already:

_(fixtures).keys().each(function(filename){
  var promise = $http.get(BASE_URL + filename).then(function(response) {
    fixtures[filename] = response.data;
  }, function(response) {
    throw new Error('Cannot get fixture ' + filename + ' ' + status + ' ' + data );
  });
  promises.push(deferred.promise);
});

Yes you are right, but I had in mind to expose a getPromise method as well, it's why I was unwrapping the response object. See latest version.