1407098 - stylo-blocklist: put a nightly only domain in stylo blocklist for testing

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, defect, P3)

Description

[Jeremy Chen ([e-mail])]

At present, the stylo blocklist is empty in all channels. We can consider put a real site domain, e.g., mozilla.org ? to do some real site tests/verifications. The domain could be easily limited in Nightly channel.

Comment 1

[Xidorn Quan [:xidorn] UTC+10]

I can donate my arewestyloyet.rs domain if people want to use it for testing (we never formally made use of that domain, so it's quite a waste...)

Comment 2

[Jeremy Chen ([e-mail])]

I think it depends on what do we expect to test/verify with it. If we just want to verify that the mechanism is actually working, probably we could put a test page on that domain and put some words to mention the style backend for page. For example,

```
<p>
If you see XXX below, the page is styled by stylo; otherwise, the page is blocked by stylo blocklist and fallback to be styled by gecko.
</p>
<div>
[refer to Bug 1365771 (stylo-behavior-changes) to make a case here]
</div>

```


Not sure if we will need to upload more cases to the domain and do the verification, it's unclear to me if this would gain us any good at present.

Hi Chris, is there any other scenario that you can think of using this kind of nightly only blocked domain for?

Comment 3

[Xidorn Quan [:xidorn] UTC+10]

I think there are several things we want to check:
1. sites not mentioned in the list should not be affected
2. sites in the list should have stylo backend
3. a mix of sites in and not in that list in a single page should not lead to any issue

Having a special domain should be enough for 1 and 2, and to some extent 3. But I think we really want to have more coverage on 3, in that case, we probably should randomly include some popular websites in the list somehow in Nightly.

Comment 4

[Chris Peterson [:cpeterson]]

How can QA determine whether a page is using Stylo or the old Gecko style system? Can we create a test page that looks for some Stylo-specific CSS feature and then reports "You are using Stylo" or "You are using the old Gecko style system"?

Comment 5

[Cameron McCormack (:heycam)]

Yes, per comment 2 I think we just need to pick one of the bug 1379467 blockers to make test from.  Bug 1379467 looks like an easy one to do this with.

Comment 6

[Cameron McCormack (:heycam)]

Attachment: stylo check

Like this.  It would need to be served from whatever domain you decide to add to the blocklist, of course.

Comment 7

[Jeremy Chen ([e-mail])]

As comment 1 and comment 6 said, I think we're ready for creating a stylo test website. Xidorn, could you help upload the file (made by heycam in comment 6) to your arewestyloyet.rs domain?

Comment 8

[Jeremy Chen ([e-mail])]

Attachment: Bug 1407098 - put a nightly only domain in stylo blocklist for testing.

Thanks to xidorn's donation, now we can do some real domain testings for stylo
blocklist mechanism. Note that we only add arewestyloyet.rs domain in Nightly
channel for testing, and the domain should be removed in other channels.

Review commit: https://reviewboard.mozilla.org/r/189400/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/189400/

Comment 9

[Xidorn Quan [:xidorn] UTC+10]

(In reply to Cameron McCormack (:heycam) (away 24 Oct – 12 Nov) from comment #6)
> Created attachment 8918203 [details]
> stylo check
> 
> Like this.  It would need to be served from whatever domain you decide to
> add to the blocklist, of course.

This doesn't work for non-stylo. I get an unstable result on Firefox 56 :/

I get things like:
* stylo is ... not sure (-3924.45px)
* stylo is ... not sure (-3.57914e+7px)
* stylo is ... not sure (-104468px)

(That probably means we are doing something more wrong than just not supporting that.)

Comment 10

[Xidorn Quan [:xidorn] UTC+10]

Looks like this is fixed in Firefox 57 (when stylo is disabled).

Comment 11

[Xidorn Quan [:xidorn] UTC+10]

Attachment: another stylo check

This should be a more precise stylo check based on bug 1374885.

Comment 12

[Xidorn Quan [:xidorn] UTC+10]

I've updated https://arewestyloyet.rs/ with a testing page.

Please check the source code of the page and its script / style (since there are some invisible elements) and tell me if there is anything can be improved.

Comment 13

[Jeremy Chen ([e-mail])]

(In reply to Xidorn Quan [:xidorn] UTC+10 from comment #12)
> I've updated https://arewestyloyet.rs/ with a testing page.
> 
> Please check the source code of the page and its script / style (since there
> are some invisible elements) and tell me if there is anything can be
> improved.

Xidorn, I've verified it works as expected with:

* stylo enabled
* stylo disabled
* stylo enabled with "arewestyloyet.rs" in the blocklist

Thank you for making this fantastic testing page. Looks awesome!!

Comment 14

[Xidorn Quan [:xidorn] UTC+10]

Unfortunately, this page can only distinguish between WebKit-based browsers and Gecko-based browsers, and it would incorrectly report Edge as using Stylo :/

Comment 15

[Xidorn Quan [:xidorn] UTC+10]

Comment on attachment 8918539 [details]
Bug 1407098 - put a nightly only domain in stylo blocklist for testing.

https://reviewboard.mozilla.org/r/189400/#review194678

Comment 16

[Jeremy Chen ([e-mail])]

(In reply to Xidorn Quan [:xidorn] UTC+10 (less responsive Nov 5 ~ Dec 16) from comment #14)
> Unfortunately, this page can only distinguish between WebKit-based browsers
> and Gecko-based browsers, and it would incorrectly report Edge as using
> Stylo :/

We can surely put more script to detect different browsers. However, this page should be mostly used for testing Firefox, so I don't think it is worth to put more efforts for other browsers at the moment.

Comment 17

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f0600bdbba0f
put a nightly only domain in stylo blocklist for testing. r=xidorn

Comment 18

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/f0600bdbba0f