To get away from the ancient (and buggy) text layout code in
Gfx::Painter, we want to remove all the uses of Painter::draw_text().
As a first step towards this, we implement the draw_text() display list
command in terms of the draw_text_run() command by performing the very
simple necessary layout in draw_text() beforehand.
Our current segmenter implementation lives in LibUnicode, and is not
locale-aware. We will need such awareness for ECMA-402, and so LibLocale
will be the new home for text segmentation.
The tests here are ported directly from LibUnicode/TestSegmentation.cpp.
There are a couple of differences here due to using ICU:
1. Titlecasing behaves slightly differently. We previously transformed
"123dollars" to "123Dollars", as we would use word segmentation to
split a string into words, then transform the first cased character
to titlecase. ICU doesn't go quite that far, and leaves the string
as "123dollars". While this is a behavior change, the only user of
this API is the `text-transform: capitalize;` CSS rule, and we now
match the behavior of other browsers.
2. There isn't an API to compare strings with case insensitivity without
allocating case-folded strings for both the left- and right-hand-side
strings. Our implementation was previously allocation-free; however,
in a benchmark, ICU is still ~1.4x faster.
Add the missing `print` function to the spectest namespace. Also, spec
externs cannot be re-used because operations that modify "memory", for
example, will carry over into subsequent spec test runs. This can be
remedied in the future by implementing some sort of garbage collector
for allocations in the store.
The values aren't that complex, so it doesn't make much sense to have a
dedicated generator for them. Parsing them manually also allows us to
have much more control over the produced values, so as a result of this
change, EasingStyleValue becomes much more ergonomic.
...and shadow tree with TextNode for "value" attribute is created.
This means InlineFormattingContext is used, and button's text now
respects CSS text-decoration properties and unicode-ranges.
This uses ICU for the Intl.DateTimeFormat `format` `formatToParts`,
`formatRange`, and `formatRangeToParts`.
This lets us remove most data from our date-time format generator. All
that remains are time zone data and locale week info, which are relied
upon still for other interfaces. So they will be removed in a future
patch.
Note: All of the changes to the test files in this patch are now aligned
with other browsers. This includes:
* Some very incorrect formatting of Japanese symbols. (Looking at the
old results now, it's very obvious they were wrong.)
* Old FIXMEs regarding range formatting not including the start/end date
when only time fields were requested, but the dates differ.
* Day period inconsistencies.
The [UTF-8](https://datatracker.ietf.org/doc/html/rfc3629#page-5)
standard says to reject strings with upper or lower surrogates. However,
in many standards, ECMAScript included, unpaired surrogates (and
therefore UTF-8 surrogates) are allowed in strings. So, this commit
extends the UTF-8 validation API with `AllowSurrogates`, which will
reject upper and lower surrogate characters.
Note: We keep locale parsing and syntactic validation as-is. ECMA-402
places additional restrictions on locales above what is required by the
Unicode spec. ICU doesn't provide methods that let us easily check those
restrictions, whereas LibLocale does. Other browsers also implement
their own validators here.
This introduces a locale cache to re-use parsed locale data and various
related structures (not doing so has a non-negligible performance impact
on Intl tests).
The existing APIs for canonicalization and display names are pretty
intertwined, so they must both be adapted at once here. The results of
canonicalization are slightly different on some edge cases. But the
changed results are actually now aligned with Chrome and Safari.
Instead of attempting a stack use-after-free by reading an out-of-scope
object's data member, let's keep a flag that checks if the destructor
had been called in the outer scope.
Fixes#64
