This fixes an issue where whitespace inside embedded <svg> elements
would create unexpected whitespace text content on the page.
When combined with something like `white-space: pre-wrap`, it ended
up generating a lot of surprising vertical offsets.
Previously, we had three layout modes:
- Normal:
- Everything uses the computed values from CSS.
- MinContent:
- Containing blocks act as if they have 0 width.
- All line breaking opportunities are taken.
- MaxContent:
- Containing blocks act as if they have infinite width.
- Only forced line breaks are accepted.
The above was based on a set of misunderstandings of CSS sizing.
A major problem with the above was that *all* containing blocks
behaved differently during intrinsic size layout, not just the
relevant one.
With this patch there are only two layout modes:
- Normal:
- Everything uses the computed values from CSS.
- IntrinsicSizeDetermination:
- One or more boxes have size constraints applied.
There are two size constraints per layout box, set here:
- FormattingState::NodeState::width_constraint
- FormattingState::NodeState::height_constraint
They are of type SizeConstraint and can be one of None, MinContent,
or MaxContent. The default is None.
When performing an IntrinsicSizeDetermination layout, we now assign
a size constraint to the box we're trying to determine the intrinsic
size of, which is then honored by using two new helpers to query
the dimensions of containing blocks:
- FormattingContext::containing_block_width_for(Box)
- FormattingContext::containing_block_height_for(Box)
If there's a relevant constraint in effect on the Box, the size of
its containing block is adjusted accordingly.
This is essentially an implementation of the "available space"
constraints from CSS-SIZING-3. I'm sure some things will break from
this, and we'll have to deal with that separately.
Spec: https://drafts.csswg.org/css-sizing-3/#available
Before this change, IFC would first generate all of its line boxes
and then measure them. It would then write some of the values into
the state of the IFC's containing block.
We now move that up to BFC::layout_inline_children() instead, which
is a much more natural place to decide metrics for the block.
Instead of allowing FormattingContext to instantiate an IFC for anything
that has inline children, move this logic to BFC.
This is fine, since only BFC deals with blocks having inline children
anyway.
Before, querying any of the four intrinsic sizes would cause us to
calculate all of them (the four being min-content width/height, and
max-content width/height).
Now, the helper functions only calculate the specific intrinsic size
requested. It's then cached at the root formatting context level,
so that it's never calculated twice within the same layout pass.
In cases where flex item cross size is based on the flex line cross
size, the spec specifically says to transfer the *outer* cross size of
the line. We were ignoring the "outer" part.
This patch fixes that by subtracting the cross margins from the size.
Instead of using Optional<LengthPercentage>, we now use LengthPercentage
for these values. The initial values are all `auto`.
This avoids having to check `has_value()` in a ton of places.
This patch adds support for URLSearchParams to XHR::send() and
introduces the union type XMLHttpRequestBodyInit.
XHR::send() now has support for String and URLSearchParams.
Anonymous wrappers get their non-inherited properties from the initial
state of a new CSS::ComputedValues object. Before this patch, all the
values in their margin and padding LengthBox would be "auto".
Instead of recomputing the "remaining free space" per flex line,
remember it after calculating it during the "resolve flexible lengths"
step so we can reuse it later.
When we're performing max-content layout (a separate throwaway layout
pass that only exists to discover the intrinsic max-content size of
a specific box), we act as if the containing block has infinite width.
This allows an infinite length to propagate into the layout system,
which is fine, but at some point it needs to be turned into a finite
number or some loop conditions will not make sense and we can hang
indefinitely (e.g in the flexible lengths resolution algorithm.)
We fix this by making Length::resolved() turn non-finite values into
an "auto" length.
This commit has no behavior changes.
In particular, this does not fix any of the wrong uses of the previous
default parameter (which used to be 'false', meaning "only replace the
first occurence in the string"). It simply replaces the default uses by
String::replace(..., ReplaceMode::FirstOnly), leaving them incorrect.
The main thing that is missing is validating certain pieces of data
against XML productions in well-formed mode, but nothing uses
well-formed mode right now.
Required by Closure Library for sanitising HTML.
e687b3d8ab/closure/goog/html/sanitizer/safedomtreeprocessor.js (L117)
This a simple RAII helper for the BorderRadiusCornerClipper it
samples under the corners on construction, then blits them back
on exiting the scope. This encapsulates a fairly common pattern.
Note: With this change the border-radius is clipped if ethier the
overflow-x or overflow-y is hidden (it is a little unclear what
happens if just one is set, but it seems like most browsers
treat one set + border-radius the same as if overflow: hidden
was set).
