In a similar way to Position, now specified and computed gradients share
a common Gradient type defined in style::values::generics::image.
This allows us to reuse most code for many style traits like ToCss,
HasViewportPercentage and ToComputedValue.
The test changes are the fallout of the disappearance of AngleOrCorner::None,
which align our code to the spec for serialisation, where components that can
be omitted should be omitted.
A specified position is now a struct made of two values of different types,
the first one being PositionComponent<X>, and the second one PositionComponent<Y>.
A position component is represented by the new enum PositionComponent<Side>,
with the three values Center, Length(LengthOrPercentage), and
Side(Side, Option<LengthOrPercentage>).
Side keywords are represented by the X and Y enums, which don't include a value
for the center keyword anymore. They are accompanied by the Side trait, which
allows us to determine whether a side keyword is "left" or "top".
This refactor simplified the parsing and serialisation code and exposed bugs in it,
where it would reject valid <position> values followed by arbitrary tokens,
and where it would fail to prefer "left" to "right" when serialising positions
in basic shapes.
To make it possible to check the rule type when parsing lengths, we need to pass
the `ParserContext` down through many layers to the place where length units are
parsed.
This change leaves it unused, so it's only to prepare for the next change.
MozReview-Commit-ID: 70YwtcCxnWw
style: Do not immediately convert absolute specified lengths
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This PR aims to solve issue #15729. I tried to follow the recommendations there as much as possible.
This is my first attempt at contributing to Servo, so this will probably need a lot of input, although I'm eager to make it as polished as possible.
- The base inaccuracy issue seems solved, as can be easily verified with the `console.log` based example in the issue.
- Very basic unit tests were added.
I have doubts mainly about the right way to represent these new enum variants for the various length units:
1. With new enum variants in `NoCalcLength` *and* newtypes (current solution)
2. With a `NoCalcLength::Absolute` variant that contains a new `AbsoluteLength` enum, but without newtypes
3. Same as solution 2 but with newtypes
- I mostly cared about unit tests until now but will investigate other types of tests
- Tests to check the clamping
- Write a proper commit message
Thanks for your time and feedback :)
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#15729.
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- [X] There are tests for these changes
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The NoCalcLength::Absolute variant has been rewritten to accommodate
other units than Au with the new AbsoluteLength enum. This avoids loss
of precision for some operations.
The conversion from floating point absolute lengths to integer
application unit values adopts the same clamping limits as Gecko.
First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once https://github.com/w3c/csswg-drafts/issues/1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.
The parser of image-orientation is also fixed to report parsing errors on
empty string.
Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.
Gecko bug: Bug 1341758
Preserve more information from transform function parsing.
Preserve angle unit while parsing.
Simplify SpecifiedMatrix.
Use the write! macro for formatting with a helper called Css.
Implement ToCss for &T if T implements ToCss.
Add some tests and update others.
closes#15194
It's a bit unfortunate the use separate implementations of SpecifiedUrl for Servo
and Gecko, but they're different enough at this point that I don't think it really
makes sense to try to share everything. Splitting them out has some nice
simplifications as well.
I recognize that there's still some potential correctness issues for Servo using
the resolved URI in various places where the original URI may be the right thing,
but I've got too much on my plate to look into that for now.
MozReview-Commit-ID: BeDu93TQ4Ow
