1367647 - stylo: have a way to request a restyle that recascades the entire tree

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, enhancement)

Description

[Cameron McCormack (:heycam)]

We need some way to request that cascading of a tree's descendants happens even when there is no restyle hint indicating we need to re-selector match, and when the parent's style didn't change.  This is so that we can handle changes to, for example, system colors, which affect the style value computation process.

This is the second part of (3) in bug 1334732.

Comment 1

[Cameron McCormack (:heycam)]

Bobby's suggestion in bug 1334732 comment 0 is to expand the current boolean that determines whether we must cascade children into a CascadeHint.  Although I think it would work just as well as new RestyleHint flags.

Comment 2

[Cameron McCormack (:heycam)]

Attachment: style: Support a restyle hint that indicates all descendants must be recascaded.

This also moves the result of deciding whether to recascade from the
RestyleData into the RestyleHint.

Review commit: https://reviewboard.mozilla.org/r/143734/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/143734/

Comment 3

[Cameron McCormack (:heycam)]

Attachment: Bug 1367647 - Test expectation updates.

Review commit: https://reviewboard.mozilla.org/r/143736/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/143736/

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Comment on attachment 8872247 [details]
style: Support a restyle hint that indicates all descendants must be recascaded.

https://reviewboard.mozilla.org/r/143734/#review147520

::: servo/components/style/restyle_hints.rs:422
(Diff revision 1)
> +        // inherited values after restyling for animations, and thus we
> +        // want to remove it so that we don't later try to restyle the element
> +        // during a normal restyle.  (We could have separate
> +        // RECASCADE_SELF_NORMAL and RECASCADE_SELF_ANIMATIONS flags to make it
> +        // clear, but this isn't currently necessary.)
> +        self.recascade.remove(RECASCADE_SELF);

Hmm... This is indeed tricky, but I guess it's fine. Thanks for the comment.

Comment 5

[Emilio Cobos Álvarez (:emilio)]

Comment on attachment 8872248 [details]
Bug 1367647 - Test expectation updates.

https://reviewboard.mozilla.org/r/143736/#review147522

Comment 6

[Cameron McCormack (:heycam)]

Comment on attachment 8872248 [details]
Bug 1367647 - Test expectation updates.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/143736/diff/1-2/

Comment 7

[Cameron McCormack (:heycam)]

https://github.com/servo/servo/pull/17087

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/d43415e71e01
Test expectation updates. r=emilio

Comment 9

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/d43415e71e01