style: Implement the non-functional :host selector.
Kinda tricky because :host only matches rules on the shadow root where the rules
come from. So we need to be careful during invalidation and style sharing.
I didn't use the non_ts_pseudo_class_list bits because as soon as we implement
the :host(..) bits we're going to need to special-case it anyway.
The general schema is the following:
* Rightmost featureless :host selectors are handled inserting them in the
host_rules hashmap. Note that we only insert featureless stuff there. We
could insert all of them and just filter during matching, but that's slightly
annoying.
* The other selectors, like non-featureless :host or what not, are added to the
normal cascade data. This is harmless, since the shadow host rules are never
matched against the host, so we know they'll just never match, and avoids
adding more special-cases.
* Featureless :host selectors to the left of a combinator are handled during
matching, in the special-case of next_element_for_combinator in selectors.
This prevents this from being more invasive, and keeps the usual fast path
slim, but it's a bit hard to match the spec and the implementation.
We could keep a copy of the SelectorIter instead in the matching context to
make the handling of featureless-ness explicit in match_non_ts_pseudo_class,
but we'd still need the special-case anyway, so I'm not fond of it.
* We take advantage of one thing that makes this sound. As you may have
noticed, if you had `root` element which is a ShadowRoot, and you matched
something like `div:host` against it, using a MatchingContext with
current_host == root, we'd incorrectly report a match. But this is impossible
due to the following constraints:
* Shadow root rules aren't matched against the host during styling (except
these featureless selectors).
* DOM APIs' current_host needs to be the _containing_ host, not the element
itself if you're a Shadow host.
Bug: 992245
Reviewed-by: xidorn
MozReview-Commit-ID: KayYNfTXb5h
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Kinda tricky because :host only matches rules on the shadow root where the rules
come from. So we need to be careful during invalidation and style sharing.
I didn't use the non_ts_pseudo_class_list bits because as soon as we implement
the :host(..) bits we're going to need to special-case it anyway.
The general schema is the following:
* Rightmost featureless :host selectors are handled inserting them in the
host_rules hashmap. Note that we only insert featureless stuff there. We
could insert all of them and just filter during matching, but that's slightly
annoying.
* The other selectors, like non-featureless :host or what not, are added to the
normal cascade data. This is harmless, since the shadow host rules are never
matched against the host, so we know they'll just never match, and avoids
adding more special-cases.
* Featureless :host selectors to the left of a combinator are handled during
matching, in the special-case of next_element_for_combinator in selectors.
This prevents this from being more invasive, and keeps the usual fast path
slim, but it's a bit hard to match the spec and the implementation.
We could keep a copy of the SelectorIter instead in the matching context to
make the handling of featureless-ness explicit in match_non_ts_pseudo_class,
but we'd still need the special-case anyway, so I'm not fond of it.
* We take advantage of one thing that makes this sound. As you may have
noticed, if you had `root` element which is a ShadowRoot, and you matched
something like `div:host` against it, using a MatchingContext with
current_host == root, we'd incorrectly report a match. But this is impossible
due to the following constraints:
* Shadow root rules aren't matched against the host during styling (except
these featureless selectors).
* DOM APIs' current_host needs to be the _containing_ host, not the element
itself if you're a Shadow host.
Bug: 992245
Reviewed-by: xidorn
MozReview-Commit-ID: KayYNfTXb5h
It doesn't actually matter because this is only called from
WebGLRenderingContext::BindTexture, which already checks the target,
but better be safe than sorry.
The early return for identical setting in importance matching as well
as the comment before `index_to_remove` are removed because the order
is web-exposing regardless of whether it's from CSSOM or parsing. e.g.
`top: 1px; left: 2px; top: 1px;` is effectively `left: 2px; top: 1px;`,
not `top: 1px; left: 2px;`.
Add support for percentages in column-gap.
<!-- Please describe your changes on the following line: -->
# Changes in this PR
* I've removed the `if product == "gecko"` line in order to make the column_gap type "NonNegativeLengthOrPercentageOrNormal" always.
* Then I've changed this line
```rust
Either::First(len) => len.into(),
```
to
```rust
Either::First(len) => len.0.to_pixel_length(content_inline_size).into(),
```
---
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- [X] `./mach build-geckolib` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#20498 (github issue number if applicable).
<!-- Either: -->
- [X] These changes do not require tests because there are tests already for this in wpt, in particular css/css-align/gaps/column-gap-parsing-001.html for the parsing bits, and css/css-multicol/multicol-gap-percentage-001.html for the layout bits.
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Stop using NS_STYLE_FONT_WEIGHT_NORMAL and NS_STYLE_FONT_WEIGHT_BOLD
The Servo side of the changes for
https://bugzilla.mozilla.org/show_bug.cgi?id=1452040
- [X] `./mach build -d` does not report any errors
- [X] `./mach build-geckolib` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).
- [ ] There are tests for these changes OR
- [X] These changes do not require tests because it's a trivial change to internal constants
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This new implementation of the session history keeps track of
a single tree of browsing contexts and pipelines which represents
the active entry of the session history and it keeps track of
diffs between adjacent entries. This allows use to traverse across
the joint session history by applying diffs to the active tree.
