We will now spin in "the end" until there are no more "things delaying
the load event". Of course, nothing actually uses this yet, and there
are a lot of things that need to.
The ideal solution here is to implement a more spec-compliant event
loop, but while we get all the pieces in place for that, this at least
makes the HTML event loop a bit more responsive since it never has to
wait for a 16ms timer to fire.
The old name is the result of the perhaps somewhat confusingly named
abstract operation OrdinaryFunctionCreate(), which creates an "ordinary
object" (https://tc39.es/ecma262/#ordinary-object) in contrast to an
"exotic object" (https://tc39.es/ecma262/#exotic-object).
However, the term "Ordinary Function" is not used anywhere in the spec,
instead the created object is referred to as an "ECMAScript Function
Object" (https://tc39.es/ecma262/#sec-ecmascript-function-objects), so
let's call it that.
The "ordinary" vs. "exotic" distinction is important because there are
also "Built-in Function Objects", which can be either implemented as
ordinary ECMAScript function objects, or as exotic objects (our
NativeFunction).
More work needs to be done to move a lot of infrastructure to
ECMAScriptFunctionObject in order to make FunctionObject nothing more
than an interface for objects that implement [[Call]] and optionally
[[Construct]].
Some sites don't have favicon.ico, so we may get 404 response.
In such cases, ResourceLoader still calls success_callback.
For favicon loading, we are not checking response headers or payload
size.
This will ultimately fail in Gfx::ImageDecoder::try_create().
So avoid unnecessary work by returning early, if data is empty.
This doesn't work correctly in the new world where fonts are resolved
during the CSS cascade. Let's patch it out with a FIXME and get back to
it once everything has fallen into place.
Resolved style is a spec concept that refers to the weird mix of
computed style and used style reflected by getComputedStyle().
The purpose of this class is to produce the *computed* style for a given
element, so let's call it StyleComputer.
Once we've performed the cascade on a set of values for an element,
we should have enough information to resolve/absolutize some lengths.
Basically, any CSS length that isn't "auto" or a percentage can be
turned into an absolute length (in pixels) as long as we have the
following information:
- The viewport rect
- The parent element's font
- The document element's font
- The element's own font
To ensure that we can absolutize lengths relative to the element's own
font, we now do a separate first pass where font-related properties are
defaulted (in the cascade spec sense of the word) and become usable.
There's a lot more work to do here, but this should open up a lot of
simplification in layout code, since it will no longer need to care
about relative lengths. Layout still needs to resolve percentages, since
we can't do that for some properties until the containing block
dimensions are known.
The original name was based on the window.getComputedStyle() API.
However, "Computed" in "getComputedStyle" is actually a misnomer that
the platform is stuck with due to backwards compatibility.
What getComputedStyle() returns is actually a mix of computed and used
values. The spec calls it the "resolved" values. So let's call this
declaration subclass "ResolvedCSSStyleDeclaration" to match.
This replaces a bunch of casts with `.as_foo()` calls, and adjusts calls
to the old `is_foo()` methods that now are better as `has_foo()`.
Also tidied up some whitespace to be more consistent.
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.
Previously any children would be layout using a BlockFormattingContext.
Now we at least differentiate between IFC and BFC if the sizes in
question are not constrained by other things.
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`.
This brings us a few nice benefits:
- We only generate a `StyleValueList` for properties that accept
multiple values.
- We reject declarations that have too many values.
- We check the type of each value that is parsed, to make sure it's
acceptable to the property.
Probably there are some regressions here, since this is
Later, we can also replace many of the `is_foo()` functions and lambas
inside the Parser with more calls to `property_accepts_value()`. Also we
can remove some checks when resolving styles, since only valid types of
values will get to that point. But one step at a time. :^)
We don't want a property like `background` to fall back to parsing as a
single value or StyleValueList if `parse_background_style_value()`
fails. We just want it to fail.
