1895176 - Display @position-try rules

Status: RESOLVED FIXED

(DevTools :: Inspector: Rules, task, P3)

Description

[Nicolas Chevobbe [:nchevobbe]]

https://drafts.csswg.org/css-anchor-position-1/#fallback-rule

Comment 1

[Nicolas Chevobbe [:nchevobbe]]

Note that:

The <dashed-ident> specified in the prelude is the rule’s name. If multiple @position-try rules are declared with the same name, the last one in document order "wins".

There's no indication about how this should behave if the rule is in a grouping rule like @media, @container, @layout, @starting-style, or even a regular CSSStyleRule.

Jonathan, am I missing something from the spec, or does it mean that the last @position-try rules in the document always win, no matter if it's nested in another rule?

Comment 2

[Jonathan Watt [:jwatt]]

(In reply to Nicolas Chevobbe [:nchevobbe] from comment #1)

Jonathan, am I missing something from the spec, or does it mean that the last @position-try rules in the document always win, no matter if it's nested in another rule?

I don't think that would make sense. The spec text just needs to account for these scenarios. I've filed a spec bug at:

https://github.com/w3c/csswg-drafts/issues/11080

Comment 3

[Nicolas Chevobbe [:nchevobbe]]

Adding dependency on Bug 2004036 for now, as adding/modifying declaration from the inspector won't have any effect on the element, which could be surprising for users.
Or we could display the @position-try rule as read-only first, so we do show them in 147 (when we add support for anchor positioning), and then we can have another bug to make those editable once Bug 2004036 is fixed

Comment 4

[Nicolas Chevobbe [:nchevobbe]]

Attachment: Bug 1895176 - [devtools] Show @position-try rules. r=#devtools.

In a similar fashion to what we do for @keyframes rules, we collect the different
@position-try rules from the stylesheets of the page, and only return them
when they're actually being used in a position-try-fallback declaration.

For now, we show them as read-only, as updating the declarations of CSSPositionTryRule
is still brittle (see Bug 2004046).

A test is added to cover this.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/98b486020c1d
https://hg.mozilla.org/integration/autoland/rev/174002d3859b
[devtools] Show @position-try rules. r=devtools-reviewers,ochameau.

Comment 6

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/174002d3859b

Comment 7

[Nicolas Chevobbe [:nchevobbe]]

Attachment: Bug 1895176 - [devtools] Show @position-try rules. .

In a similar fashion to what we do for @keyframes rules, we collect the different
@position-try rules from the stylesheets of the page, and only return them
when they're actually being used in a position-try-fallback declaration.

For now, we show them as read-only, as updating the declarations of CSSPositionTryRule
is still brittle (see Bug 2004046).

A test is added to cover this.

Original Revision: https://phabricator.services.mozilla.com/D275075

Comment 8

[Pulsebot]

https://github.com/mozilla-firefox/firefox/commit/65d14cf12afd
https://hg.mozilla.org/releases/mozilla-beta/rev/cd4b93fefaf9