See https://www.w3.org/TR/css-values-3/#calc-type-checking
If the sub-expressions' types are incompatible, we discard the calc() as
invalid.
Had to do some minor rearranging/renaming of the Calc structs to make
the `resolve_foo_type()` templates work too.
This lets us produce valid CSS in its to_string() method, instead of
always adding commas as before. :^)
Also, finally added a Formatter for StyleValues.
Many of these will need to change in the future in order to include
features we don't yet support, and touching StyleValue.h is a great way
to have to wait for all of LibWeb to rebuild. I'm hoping this saves me
time in the long run. :^)
The flexbox logic confuses me so regressions are possible, though our
test page looks the same as before so it should be fine.
Renamed FlexBasis::Length -> LengthPercentage too, for clarity.
Layout::Node still treats border radii as having a single value instead
of horizontal and vertical, but one less hack is nice, and helps with
conversion to LengthPercentage. :^)
This is in a slightly weird state, where Percentages are sometimes
Lengths and sometimes not, which I will be cleaning up in subsequent
commits, in an attempt not to change all of LibWeb in one go. :^)
This option is already enabled when building Lagom, so let's enable it
for the main build too. We will no longer be surprised by Lagom Clang
CI builds failing while everything compiles locally.
Furthermore, the stronger `-Wsuggest-override` warning is enabled in
this commit, which enforces the use of the `override` keyword in all
classes, not just those which already have some methods marked as
`override`. This works with both GCC and Clang.
This represents a property value that hasn't been converted to a
"proper" StyleValue yet. That is, it's either a custom property's value,
or a value that includes `var()` references, (or both!) since neither of
those can be fully resolved at parse time.
This now outputs valid CSS representing the background, instead of
confusing debug info.
We can't guarantee that all the longhands have the same number of
values, since while that's always the case when parsing, we also create
BackgroundStyleValues when producing the resolved style, which just
combines the longhands together.
There's nothing really background-size-specific about this, but since
there is no `<size>` value type defined in the CSS spec at this time,
and background-size is the only user of it, I think this name makes more
sense. But I'm not 100% convinced.
...as opposed to storing StyleValues, which we have to later check are
IdentifierStyleValues, which store identifiers that we can convert to
Repeat values later. It's fewer allocations, and we can't end up with
invalid values by mistake. :^)
This is step 1 in removing the two `background-repeat-x/y`
pseudo-properties. Since adding the concept of compound StyleValues, we
don't need `background-repeat` to be split in two any more.
This is done a bit differently from other properties: using a
TokenStream instead of just a Vector of ComponentValues. The reason for
this is, we can then use call the same function when parsing the
`background` shorthand. Otherwise, we would have to know in advance how
many values to pass down, which basically would involve duplicating the
`background-position` parsing code inside `background`.
The StyleValue is PositionStyleValue, since it represents a
`<position>`: https://www.w3.org/TR/css-values-4/#typedef-position
Unfortunately, background-position's parsing is a bit different from
`<position>`'s, (background-position allows 3-value syntax and
`<position>` doesn't) so we'll need to come back and write a different
parsing function for that later.
This always felt awkward to me, and required a few other hacks to make
it work. Now, the request is only started when `load_bitmap()` is
called, which we do inside `NodeWithStyle::apply_style()`.
Until now, we've internally thought of the CSS "display" property as a
single-value property. In practice, "display" is a much more complex
property that comes in a number of configurations.
The most interesting one is the two-part format that describes the
outside and inside behavior of a box. Switching our own internal
representation towards this model will allow for much cleaner
abstractions around layout and the various formatting contexts.
Note that we don't *parse* two-part "display" yet, this is only about
changing the internal representation of the property.
Spec: https://drafts.csswg.org/css-display
When parsing a CSS value in the context of a CSSStyleDeclaration
camelCase property setter, we don't necessarily have a Document to
provide the CSS parser for context.
So the parser can't go assuming that there's always a Document in the
ParsingContext. And ImageStyleValue can't go assuming that there's
always a Document either. This will require some more work to get things
right, I'm just patching up the null dereference for now.
This does a few things, that are hard to separate. For a while now, it's
been confuzing what `StyleValue::is_foo()` actually means. It sometimes
was used to check the type, and sometimes to see if it could return a
certain value type. The new naming scheme is:
- `is_length()` - is it a LengthStyleValue?
- `as_length()` - casts it to LengthStyleValue
- `has_length()` - can it return a Length?
- `to_length()` - gets the internal value out (eg, Length)
This also means, no more `static_cast<LengthStyleValue const&>(*this)`
stuff when dealing with StyleValues. :^)
Hopefully this will be a bit clearer going forward. There are lots of
places using the original methods, so I'll be going through them to
hopefully catch any issues.
Calling `is_identifier()` here was wrong, since it just means you can
get an Identifier from it. This meant that an `auto` LengthStyleValue
would return true, then it would get `static_cast` to the wrong class,
and return a garbage value.
Basically, I really need to tidy up the API for StyleValue, so it's
clear whether `is_foo()` means the object is a `FooStyleValue`, or it
can just return a `foo` value.
For `number` and `integer` types, you can add a range afterwards to add
a range check, using similar syntax to that used in the CSS specs. For
example:
```json
"font-weight": {
...
"valid-types": [
"number [1,1000]"
],
...
}
```
This limits any numbers to the range `1 <= n <= 1000`.
