1919347 - Make getComputedStyle work with view-transitions pseudo-elements

Status: RESOLVED FIXED

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

Description

[Emilio Cobos Álvarez [:emilio]]

Much like bug 1919341, we need to make the second argument of getComputedStyle able to handle view transitions pseudo-elements.

Comment 1

[Boris Chiou [:boris]]

Attachment: Bug 1919347 - Support getComputedStyle() for named view transition pseudo elements if the style is not available.

First, we have to allow the functional parameter for named view
transition pseudo elements.
Also, getComputedStyle() may resolve the style lazily (i.e. call
Servo_ResolveStyleLazily()) if its style is not available. In this
case, we have to make sure the matching function work.

TODO: We still have to make sure aElement->GetPseudoElement(aPseudo) work,
by this patch or others.

Comment 2

[Boris Chiou [:boris]]

Attachment: Bug 1919347 - Fix Element::GetPseudoElement() to retrieve the computed style from the pseudo-element direcly.

In order to retrieve the current computed style, we have to look up the
view transition pseudo-element. This patch focus on the search code
mainly.

Note that it's unfortunate we cannot pass the wpt,
css/css-view-transitions/pseudo-get-computed-style.html,
because there is a JS error when running this test, and the static UA
stylesheet hasn't been imported yet.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/30536aa95afd
Support getComputedStyle() for named view transition pseudo elements if the style is not available. r=view-transitions-reviewers,emilio
https://hg.mozilla.org/integration/autoland/rev/69d86a0542f5
Fix Element::GetPseudoElement() to retrieve the computed style from the pseudo-element direcly. r=view-transitions-reviewers,emilio

Comment 4

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/30536aa95afd
https://hg.mozilla.org/mozilla-central/rev/69d86a0542f5