Jasmine Promise Matchers

Custom matchers for Angular promises and Jasmine 1.3 - 3.x.

Overview

Tests often require simple assertions about Promise resolution/rejection. This could be accomplished by spying on the Promise object or by chaining on another Promise (complete with expects statements)- but this is a lot of work. The following matchers allow basic assertions to be made about Promises via a brief expectation.

(Note that each of the below matchers triggers a $rootScope digest so that their resolve/reject methods will be triggered. You do not need to trigger this digest yourself but should be aware of it in case it impacts other asynchronous portions of your test.)

Installation

First install the library using NPM or Bower like so:

bower install jasmine-promise-matchers --save-dev
npm install jasmine-promise-matchers --save-dev

Then modify your karma.conf.js config file to load the library like so:

module.exports = function (config) {
  config.set({
    frameworks: ['jasmine'],
    files: [
      "node_modules/jasmine-promise-matchers/dist/jasmine-promise-matchers.js"
      // Your source (e.g. source/**/*.js)
      // Your tests (e.g. tests/**/*.js)
    ]
    // Other configuration
  });
};
 

Lastly be sure to load the custom Jasmine matchers before your tests run like so:

  beforeEach(function() {
    angular.mock.module('your-module');
 
    installPromiseMatchers();
 
    inject(function() {
      // Your injected services
    });
  });

By default, this matcher flushes $httpBackend, $interval, and $timeout automatically. This can be overridden when installing the matcher like so:

  beforeEach(function() {
    installPromiseMatchers({
      flushHttpBackend: false,
      flushInterval: false,
      flushTimeout: false
    });
  });

Be sure to call angular.mock.module before installing the promise matcher library (because the promise matcher installer uses the injector).

Sublime Plugin

@Hyzual has created a Sublime plugin for this library. Find our more info about that plugin here.

Matchers

toBePromise

Verifies that a value is a $q Promise.

expect(promise).toBePromise();

toBeRejected

Verifies that a Promise is (or has been) rejected.

expect(promise).toBeRejected();

toBeRejectedWith

Verifies that a Promise is (or has been) rejected with the specified parameter.

expect(promise).toBeRejectedWith('something');
 
// Asymmetric matching is also supported for objects:
expect(promise).toBeRejectedWith(jasmine.objectContaining({partial: 'match'}));

toBeResolved

Verifies that a Promise is (or has been) resolved.

expect(promise).toBeResolved();

toBeResolvedWith

Verifies that a Promise is (or has been) resolved with the specified parameter.

expect(promise).toBeResolvedWith('something');
 
// Asymmetric matching is also supported for objects:
expect(promise).toBeResolvedWith(jasmine.objectContaining({partial: 'match'}));

Development

If you'd like to contribute to this project you'll need to initialize it like so:

npm i -g karma
cd <path-to-project>
npm i
cd jasmine-1.3
npm i
cd ../jasmine-2.2
npm i
cd ../jasmine-3.1
npm i

At this point you should be able to build via grunt build and run unit tests via grunt test. Tests will be run against both Jasmine 1.3 and 2.2 flavors.