"You created a second Pretender instance while there was already one running"

See original GitHub issue

I started getting this error today with ember-cli-mirage@0.2.2, and I’m fairly certain it has to do with Pretender 1.4.0 (that has a Notify on second Pretender fix) that was released today.

beforeEach failed on visiting /myroute/foo: You created a second Pretender instance while there
was already one running. Running two Pretender servers at once will lead to unexpected
results!Please call .shutdown() on your instances when you no longer need them to respond.

This was in my acceptance test. I have failures in my integration tests as well, which look like:

Promise rejected before it renders: Assertion Failed: You cannot use the same root element
(#ember-testing) multiple times in an Ember.Application

So what is the appropriate way to shutdown the Mirage server? I currently have this in my acceptance tests:

afterEach() {
  Ember.run(application, 'destroy');
  server.shutdown();
}

Do I need something similar in my integration tests?

Issue Analytics

State:
Created 7 years ago
Reactions:19
Comments:14 (7 by maintainers)

Top GitHub Comments

6reactions

mdarmetkocommented, Jan 10, 2017

I’m using mostly default generated tests with ember 2.10 and was having this issue. Resolved it by adding if(server !== undefined) { server.shutdown(); } to beforeEach and afterEach in each acceptance test file. As in,

module('Acceptance: Metro', {
  beforeEach: function() {
    if(server !== undefined) { server.shutdown(); }
    application = startApp();
    originalConfirm = window.confirm;
    window.confirm = function() {
      confirmCalledWith = [].slice.call(arguments);
      return true;
    };
  },
  afterEach: function() {
    Ember.run(application, 'destroy');
    window.confirm = originalConfirm;
    confirmCalledWith = null;
    if(server !== undefined) { server.shutdown(); }
  }
});

Hope this helps someone else having the same problem.

6reactions

netescommented, Oct 13, 2016

Update: It seems that updating module-for-acceptance.js to the newest version (from Ember CLI 2.8) and adding this snippet to integration tests which use Mirage:

    afterEach() {
      server.shutdown();
    },

does the job - everything is fine then.

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