This patch looks bigger than it is, but it's mostly because
of plumbing.
To implement revert-layer we need not only the cascade origin of the
declaration, but the whole cascade level, plus also the layer order.
In order to do this, encapsulate these two things inside a 32-bit
`CascadePriority` struct and plumb it through the rule tree and so on.
This allows us to remove the packing and unpacking of CascadeLevel,
though I kept the ShadowCascadeOrder limit for now in case we need to
reintroduce it.
Fix `!important` behavior of layers while at it (implementing it in
`CascadeLevel::cmp`, spec quote included since it was tricky to find)
since some revert-layer tests were depending on it.
The style attribute test is failing now, but follow-up commit fixes
it, see spec issue.
In terms of the actual keyword implementation, it's sort of
straight-forward: We implement revert and revert-layer in a shared
way, by storing the cascade priority that reverted it.
Differential Revision: https://phabricator.services.mozilla.com/D133372
No behavior change, just cleanup. Actually seem this technically _adds_ some code even
though it's a cleanup, but that's mostly because of the wrapping of the
derive list. The resulting code is simpler (more in-line with our usual
things, so I think it's an improvement).
Differential Revision: https://phabricator.services.mozilla.com/D111551
This reduces the amount of assembly instructions generated by this
function from 18k+ to ~800.
This should make reasoning about its stack space usage sane, and should
fix the ASAN stack overflows, but also we should take this regardless,
because it's saner and makes reading it simpler.
I also think that the writing_mode shenanigans is fixing a bug (I think
before this, we'd pick the first physical value which mapped to any of
the properties, which is wrong), but I haven't bothered looking for a
test-case that fails before my patch. The relevant WPTs
(css/css-logical/animation*) still pass.
Differential Revision: https://phabricator.services.mozilla.com/D105342
It's only used to disambiguate between the one-argument and the trait
version of Keyword::parse. Instead, just explicitly use the trait
version, so that we don't need to specify it.
Differential Revision: https://phabricator.services.mozilla.com/D104328
It's only used to disambiguate between the one-argument and the trait
version of Keyword::parse. Instead, just explicitly use the trait
version, so that we don't need to specify it.
Differential Revision: https://phabricator.services.mozilla.com/D104328
This is just a refactor in the right direction. Eventual goal is:
* All inherited properties use ArcSlice<>.
* All reset properties use OwnedSlice<> (or ThinVec<>).
No conversion happens at all, so we can remove all that glue, and also
compute_iter and co.
Of course there's work to do, but this is a step towards that.
Differential Revision: https://phabricator.services.mozilla.com/D30127
This is just a refactor in the right direction. Eventual goal is:
* All inherited properties use ArcSlice<>.
* All reset properties use OwnedSlice<> (or ThinVec<>).
No conversion happens at all, so we can remove all that glue, and also
compute_iter and co.
Of course there's work to do, but this is a step towards that.
Differential Revision: https://phabricator.services.mozilla.com/D30127
It's not very easy to understand on its current state, and it causes subtle bugs
like bug 1533654.
It could be simpler if we centralized where the interactions between properties
are handled. This patch does this.
This patch also changes how MathML script sizes are tracked when scriptlevel
changes and they have relative fonts in between.
With this patch, any explicitly specified font-size is treated the same (being a
scriptlevel boundary), regardless of whether it's either an absolute size, a
relative size, or a wide keyword.
Relative lengths always resolve relative to the constrained size, which allows
us to avoid the double font-size computation, and not give up on sanity with
keyword font-sizes.
I think given no other browser supports scriptlevel it seems like the right
trade-off.
Differential Revision: https://phabricator.services.mozilla.com/D23070
The way the copy-on-write stuff works, and the way that we have to apply
properties from most specific to less specific guarantees that always that we're
going to inherit an inherited property, or reset a reset property, we have
already the right value on the style.
Revert relies on that, so there doesn't seem to be a reason to not use that fact
more often and skip useless work earlier.
Font-size is still special of course... I think I have a way to move the
specialness outside of the style, but piece by piece.
Differential Revision: https://phabricator.services.mozilla.com/D21882
The only fishy bit is the animation stuff. In particular, there are two places
where we just mint the revert behavior:
* When serializing web-animations keyframes (the custom properties stuff in
declaration_block.rs). That codepath is already not sound and I wanted to
get rid of it in bug 1501530, but what do I know.
* When getting an animation value from a property declaration. At that point
we no longer have the CSS rules that apply to the element to compute the
right revert value handy. It'd also use the wrong style anyway, I think,
given the way StyleBuilder::for_animation works.
We _could_ probably get them out of somewhere, but it seems like a whole lot
of code reinventing the wheel which is probably not useful, and that Blink
and WebKit just cannot implement either since they don't have a rule tree,
so it just doesn't seem worth the churn.
The custom properties code looks a bit different in order to minimize hash
lookups in the common case. FWIW, `revert` for custom properties doesn't seem
very useful either, but oh well.
Differential Revision: https://phabricator.services.mozilla.com/D21877
