Bug 266953 – Add '::placeholder' and '::file-selector-button' in isTreeAbidingPseudoElement

• Status: NEW
• Component: CSS

[Ahmad Saleem]

Hi Team,

While fixing another bug in the past (bug 265611), I came across this FIXME but couldn't find related bug, so I thought to create it so we can fix it.

WebKit Source: https://searchfox.org/wubkat/rev/af9971e796398c1d012ef5df9a09ed580d19bd17/Source/WebCore/css/parser/CSSSelectorParser.cpp#465

> // FIXME: This list should also include ::placeholder and ::file-selector-button

In the following function, we have to add:

case CSSSelector::PseudoElement::Placeholder:

and

case CSSSelector::PseudoElement::FileSelectorElement:


> We don't have 'Placeholder' and 'FileSelectorButton' here:

https://searchfox.org/wubkat/rev/af9971e796398c1d012ef5df9a09ed580d19bd17/Source/WebCore/css/CSSSelector.h#204

Just wanted to raise, so we can fix it.

Blink Source: https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/core/css/css_selector.cc;l=1401;drc=2755dd2e9f8848bdec96c5d99d12a179722df86d

Thanks!

[Ahmad Saleem]

We have WPT test as well: https://wpt.fyi/results/css/css-pseudo/parsing/tree-abiding-pseudo-elements.html?label=master&label=experimental&aligned=&q=tree-abiding

Live Link: http://wpt.live/css/css-pseudo/parsing/tree-abiding-pseudo-elements.html

But looking into 'expected' file: https://searchfox.org/wubkat/rev/af9971e796398c1d012ef5df9a09ed580d19bd17/LayoutTests/imported/w3c/web-platform-tests/css/css-pseudo/parsing/tree-abiding-pseudo-elements-expected.txt#1

I can see, these failures are progressed by:

https://commits.webkit.org/272337@main

Done by Anne - so I think we can remove this 'FIXME' now.

[Anne van Kesteren]

I looked at this and the tests don't appear to have coverage for this. In particular I don't see tests for ::slotted there in combination with ::placeholder and such.

[Ahmad Saleem]

(In reply to Anne van Kesteren from comment #2)
> I looked at this and the tests don't appear to have coverage for this. In
> particular I don't see tests for ::slotted there in combination with
> ::placeholder and such.

I noted that here:

https://searchfox.org/wubkat/rev/af9971e796398c1d012ef5df9a09ed580d19bd17/Source/WebCore/css/CSSSelector.cpp#840

and I think we can add:

case CSSSelector::PseudoElement::WebKitCustomLegacyPrefixed:

To cover both ::placeholder and ::file-selector-button in 'isTreeAbidingPseudoElement'.

[Ahmad Saleem]

This commit added 'FileSelectorButton' in Blink:

https://source.chromium.org/chromium/chromium/src/+/026588642150a261b2afee6e84073eba9299b24e

With following WPT (which we pass):

https://wpt.fyi/results/css/css-pseudo/file-selector-button-after-part.html?label=master&label=experimental&aligned=

[Radar WebKit Bug Importer]

<rdar://problem/120616880>