For now, we parse these, but don't actually consider the namespace when
matching them. `DOM::Element` does not (yet) store attribute namespaces
so we can't check what they are.
Use FlyString::from_deprecated_fly_string() in these instances instead
of FlyString::from_utf8(). As we convert to new FlyString/String we want
to be aware of these potential unnecessary allocations.
This makes selector matching significantly faster by not forcing us to
convert from FlyString to DeprecatedFlyString when matching class
selectors. :^)
DeprecatedFlyString relies heavily on DeprecatedString's StringImpl, so
let's rename it to A) match the name of DeprecatedString, B) write a new
FlyString class that is tied to String.
I thought the spec listing out the elements again was an oversight, but
it isn't, as simply inverting "is_actually_disabled" makes :enabled
apply to every element.
Previously we only considered an element disabled if it was an <input>
element with the disabled attribute, but there's way more elements that
apply with more nuanced disabled/enabled rules.
When matching selectors in HTML documents, we know that all the elements
have lowercase local names already (the parser makes sure of this.)
Style sheets still need to remember the original name strings, in case
we want to match against non-HTML content like XML/SVG. To make the
common HTML case faster, we now cache a lowercase version of the name
with each type/class/id SimpleSelector.
This makes tag type checks O(1) instead of O(n).
Now that we use a Variant for the SimpleSelector's data, we don't need
to instantiate empty structs or variables for the types that aren't
used, and so we can remove `PseudoElement::None`,
`PsuedoClass::Type::None` and `Attribute::MatchType::None`.
Also, we now always initialize a SimpleSelector with a type, so
`SimpleSelector::Type::Invalid` can go too.
This doesn't have parsing support for multiple languages in the same
selector. Support for language subcodes is not great either. But it
does do the basics.
In Selectors level 4, `:nth-child()` and `:nth-last-child()` can both
optionally take a selector-list argument. This selector-list acts as a
filter, so that only elements matching the list are counted. For
example, this means that the following are equivalent:
```css
:nth-child(2n+1 of p) {}
p:nth-of-type(2n+1) {}
```
Previously we were only matching elements with *no* text children.
With this patch, we now also allow any number of empty text children to
be present as well.
1% progression on ACID3. :^)
Since each selector can only have zero or one pseudo-element, we match
against it as a separate step, before matching the rest of the
selector. This should be faster, but mostly I did this because I could
not figure out how else to stop selectors without a pseudo-element from
matching the pseudo-element, eg so `.foo` styles don't affect
`.foo::before`.
Change all the places that were including the deprecated parser, to
include the new one instead, and then delete the old parser code.
`ParentNode::query_selector[_all]()` now treat their input as a
comma-separated list of selectors, instead of just one, and return
elements that match any of the selectors in that list. This is according
to these specs:
- querySelector/querySelectorAll:
https://dom.spec.whatwg.org/#ref-for-dom-parentnode-queryselector%E2%91%A0
- selector matching algorithm:
https://www.w3.org/TR/selectors-4/#match-against-tree
This is three small, related changes:
1. Element::has_attribute() now returns true if the attribute exists but
has no value. (eg, `<div foo />` -> `has_attribute("foo")`)
2. SelectorEngine::matches_attribute() now makes sure there is a first
segment before comparing it, fixing a crash.
3. CSS::Parser now converts attribute names in attribute selectors to
lowercase, to match the expectations of the rest of the system.
Converting to lowercase is not always correct, depending on language,
but since we only currently support HTML, and that expects them to be
case-insensitive, it is fine for now.
- CompoundSelector -> *deleted*
- ComplexSelector -> CompoundSelector
- Relation -> Combinator
Our Selector is really a ComplexSelector, but only the Parser and
SelectorEngine need to know that, so keeping it named Selector makes it
more understandable for users.
Our CompoundSelector is really a CompoundSelectorAndCombinator.
Combining the two makes sense in our codebase, but the accurate name is
so long that I think it makes the code less readable.
Renamed some Combinators to also match the spec terminology:
- AdjacentSibling -> NextSibling
- GeneralSibling -> SubsequentSibling
The previous names are somewhat ambiguous, so hopefully this is clearer.
Rather than parsing the selector every time we want to check it, we
now parse it once at the beginning.
A bonus effect of this is that we now support a selector list in
:not(), instead of just a single selector, though only when using
the new parser.
