Getting error "Cannot read property 'afterContentPaint' of null" when running tests

[nrcjbarry]

Occasionally on our build server, I get a failing test with the following error: Cannot read property 'afterContentPaint' of null

There are only 2 hits on Google for afterContentPaint, and one of them is this issue: ember-app-scheduler/ember-app-scheduler#9

This addon seems to be the only thing using that library. Have you ran into this error while using ember-router-scroll?

[briangonzalez]

@cclo7 Any ideas?

[nrcjbarry]

I am using headless Chrome to run my tests with this testem.js config:

module.exports = {
  test_page: 'tests/index.html?hidepassed',
  disable_watching: true,
  launch_in_ci: [
    'Chrome'
  ],
  launch_in_dev: [
  ],
  browser_args: {
    Chrome: [
      '--disable-gpu',
      '--headless',
      '--remote-debugging-port=9222',
      '--window-size=1440,900'
    ]
  }
};

[cclo7]

@nrcjbarry what type of tests are you running when encountering this error? Acceptance, integration, or unit test?

[nrcjbarry]

@cclo7 I have only seen it happen in acceptance tests.

[kpfefferle]

I too am getting this during (some) acceptance tests

[cclo7]

@sreedhar7 any ideas?

[nrcjbarry]

I also get this on my local machine too both when running ember test and ember test --server. I'm using Ember 2.15 and Ember CLI 2.15.1.

Here is a screen shot of the stack trace on one of them:

[YoranBrondsema]

I encountered the same issue after an upgrade to Ember.js 2.15. I dug a bit deeper into it and I may have found out the cause. I don't think the error is in ember-router-scroll but rather in ember-app-scheduler.

I provide more explanation here: ember-app-scheduler/ember-app-scheduler#11.

[YoranBrondsema]

Nevermind, I got it wrong... I figured out later that this addon uses an old version of ember-app-scheduler. PR #73 updates it to the latest version and that fixed the problem for me.

[ryanto]

I'm still getting this error in my application's acceptance tests. Wondering if 0.2.0 fixed it for everyone else?

[RobbieTheWagner]

@ryanto do you mean 0.4.0? That is the latest release.

[nrcjbarry]

@ryanto it was fixed for me for months up until I upgraded to Ember 3.0 last week. I started seeing this error again only on one test (the same test) every time. I fixed it by deleting my package-lock.json file and doing another npm install. I haven't seen it in the last 2 days.

[ryanto]

I'm running master, but this could be something I'm doing in my app. Just wanted to ask.

[snewcomer]

I haven't seen this error in a month or so (which before saw quite often in our CI build...on 0.4.0 then). Note we are on [email protected] and 0.5.0 for ember-router-scroll @ryanto

[bantic]

I'm still seeing this error as well, fairly sporadically in acceptance tests. Using ember-router-scroll 0.5.0 and ember-app-scheduler 0.2.1. Still looking into why, but I'm curious if anyone else is still getting it, or has a suggestion for a fix.

[snewcomer]

@bantic I think it is 👇. It's close to being done...made a PR to get the tests passing and have been awaiting feedback. Maybe I should push to his master instead 🤔

ember-app-scheduler/ember-app-scheduler#15

[ryanto]

Still seeing this. From following development on ember-app-scheduler it looks like this PR could maybe be a fix.

#129

Update: Unfortunately that PR does not fix it.

[samselikoff]

I believe we're still seeing this, and the root cause is the issue in ember-app-scheduler. If it's still an issue (and wasn't fixed by #73), could we have this issue re-opened to make the communication & updates easier to follow?

[snewcomer]

@samselikoff @ryanto What version are you guys on? Still master? I perhaps would have thought the PR to make app-scheduler optional would have fixed it. I would imagine your code is never calling scheduleWork, right?

https://github.com/dollarshaveclub/ember-router-scroll/blob/master/addon/index.js#L32

[ryanto]

Ah thanks for pointing that out! I didn't realize this was an option... Let me give it a try.

[rtablada]

@snewcomer/@ryanto heads up the issue actually seems to lie in the flushQueue from Ember App Scheduler which runs even though router-scroll isn't directly using it. Since the service is still injected and initialized these lifecycles are still happening.

I have made a PR ember-app-scheduler/ember-app-scheduler#45 to address this and check for service lifecycles.

[rtablada]

I'm not sure how ember-app-scheduler will handle porting back to version 2.* as listed as a dependency for ember-router-scroll.

[snewcomer]

@ryanto @bantic Whenever you have a chance, mind giving this branch a spin? I tried it and seems to work great. Just probably need another approval and we can merge and release a new version!

#139