This lets us get the Length and Color values directly, without having to
create a StyleValue object and then throw it away again, when parsing
the box-shadow property in the next commit.
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.
Parsing this pattern from CSS tokens turns out to be slightly crazy, but
thankfully well documented in the spec.
The spec lists the cases in order of simple -> complicated, but this
would cause problems in code, since `<n-dimension> <signed-.integer>`
would never by reached, as `<n-dimension>` comes before. Instead, I
have grouped them by their first token.
Also renamed the NthChildPattern class to ANPlusBPattern, to match spec
terminology.
The spec does not directly tell us how to parse selectors, so there are
likely some bugs here, but I've used the spec language where possible.
This is very much based on the previous selector parsing code.
Any parse error inside a selector makes the entire SelectorList
invalid, so nothing is returned.
- 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.
This was a hack copied over from the old parser, but it was causing
problems with flex-grow, and probably other properties that accept
numbers. Removing it does not seem to break anything, so lets' remove
it! :^)
Also added css-import.html, which tests the 3 syntax variations on
`@import` statements. Note that the optional media-query parameter to
`@import` is not handled yet.
We immediately use this in CSSStyleDeclaration to fix that "background"
in element.style did not return true.
This is the mechanism used in css3test.com for detecting support of
features.
This adds support for box-shadows to the DeprecatedCSSParser. When it
encounters a box-shadow property, the following syntaxes can get parsed:
- box-shadow: <offset_x> <offset_y> <color>
- box-shadow: <offset_x> <offset_y> <blur_radius> <color>
There is other possible data following the property, but those aren't
supported for now.
This patch spreads box-shadows around:
- The Values important to box-shadows are stored in a BoxShadowData
struct
- StyleProperties knows how to construct such a struct from a
BoxShadowStyleValue and a Node knows how to ask for it
- CalculatedValues contain BoxShadowData and expose them
This patch finally adds the actual calculation that goes into calc()
expressions. When the resolution of a Length that is a calculated value
the parsed CalculatedStyleValue gets traversed and appropriate values
get calculated.
This is a bit hackish, but this way the existance of the calc()
becomes transparent to the user who just wants a Length and doesn't
care where it came from.
This patch adds the parsing of previously tokenized calc() expressions
into the CSS-Parser. The tokens are processed into a complete
CalculatedStyleValue.
This detects and resolves these in the text-decoration property, in any
order:
- text-decoration-color
- text-decoration-line
- text-decoration-style
Only the solid underline renders, but all three sub-properties are
assigned correctly.
The font property now resolves into its various parts:
- font-family
- font-weight
- font-size
- font-style
- line-height
The font-variant and font-stretch parts are left unparsed since LibWeb
doesn't know how to render those.
Added `fonts.html` as a test for various forms of `font` declarations,
based on the examples in the spec.
This resolves the three sub-properties, appearing in any order:
- list-style-image
- list-style-position
- list-style-type
Added `list-style-position` values to support this, though they are not
yet used in rendering.
This was broken when we switched away from using StringStyleValues.
While I was at it, I have implemented hsl/a() and the percentage
syntax for rgb/a().
As a bonus, added `colors.html` as a test page for the various CSS
color syntaxes, since nothing was testing rgb() or rgba() before.
Much of the parsing code in LibGFX/Color.h seems to be centered
around CSS color values, but this is not used by the new Parser.
(And can't be used, because it requires a String value and we have
a list of Tokens of some kind instead.) Maybe that should be removed
from there when the new CSS parser is operational.
This implements a lot of cases, but not all of them. The following
need more infrastructure first:
- Flex
- FlexFlow
- Background
- BackgroundImage
- BackgroundRepeat
- ListStyle and parts
- Font
Also, colors are not parsed correctly. This will be handled next.
Now that StyleResolver is going to deal with StyleComponentValueRules,
it will need to be able to parse those into StyleValues, using
`parse_css_value()`.
Also added StyleValue::is_builtin_or_dynamic(), which returns true for
values that are valid anywhere - things like `initial` and `inherit`,
along with `var()`, `attr()` and `calc()` - which we want to test for
easily.
We skip whitespace tokens while doing this. As far as I can tell,
whitespace is not useful once we get to this point, and it legally
may or may not appear between any two tokens. By not including it
in the ValueListStyleValue, we make the "if it has 3 parts"-type
checks a lot more straightforward.
As the new CSS parser tokenizes its input, we can no longer easily
rely on a StringStyleValue for multi-value properties. (eg, border)
ValueListStyleValue lets us wrap all of the ComponentValues that
the Parser produced for one declaration, as a single StyleValue, to
then be parsed into StyleValues by the StyleResolver.
Originally, I wanted it to be a list of StyleValues, but several
properties use syntax that makes use of non-StyleValue tokens, eg:
```css
/* Syntax using a / */
font: 12px/14px sans-serif;
/* Multiple values separated by commas */
background: url(catdog.png), url(another-image.jpg), blue;
```
Passing the ComponentValue tokens themselves means that all that
information is carried over. The alternative might be to create a
StyleValue subclass for each property and parse them fully inside
the Parser. (eg, `FontStyleValue`)
I decided against `ListStyleValue` as a name, to avoid confusion
with list styles. It's not ideal, but names are hard.
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.
The end goal is to make the PseudoClass::not_selector be a Selector
instead of a String that is repeatedly re-parsed. But since Selector
contains a Vector of ComplexSelectors, which each have a Vector of
SimpleSelectors, it's probably a good idea to not be passing them
around by value anyway. :^)
Same reasoning again! This is the last one.
While I was at it, I added the two remaining CSS2.2 pseudo-elements,
::first-line and ::first-letter. All 4 are handled in the new CSS
parser, including with the compatibility single-colon syntax. I have
not added support to the old parser.
Previously, SimpleSelectors optionally had Attribute-selector data
as well as their main type. Now, they're either one or the other,
which better matches the spec, and makes parsing and matching more
straightforward.
Calling is_valid_escape_sequence() with no arguments hides what it
is operating on, so I have removed that, so that you must explicitly
tell it what you are testing.
The call from consume_a_token() was using the wrong tokens, so it
returned false incorrectly. This was resulting in corrupted output
when faced with this code from Acid2. (Abbreviated)
```css
.parser { error: \}; }
.parser { }
```
Had to adjust some places that were using Token.to_string() for
non-debug-logging purposes. Changed its name to to_debug_string()
to make the usage clearer.
