HTMLParser::the_end() had three spin_until calls that blocked the event
loop: step 5 (deferred scripts), step 7 (ASAP scripts), and step 8
(load event delay). This replaces them with an HTMLParserEndState state
machine that progresses asynchronously via callbacks.
The state machine has three phases matching the three spin_until calls:
- WaitingForDeferredScripts: loops executing ready deferred scripts
- WaitingForASAPScripts: waits for ASAP script lists to empty
- WaitingForLoadEventDelay: waits for nothing to delay the load event
Notification triggers re-evaluate the state machine when conditions
change: HTMLScriptElement::mark_as_ready, stylesheet unblocking in
StyleElementBase/HTMLLinkElement, did_stop_being_active_document, and
DocumentLoadEventDelayer decrements. NavigableContainer state changes
(session history readiness, content navigable cleared, lazy load flag)
also trigger re-evaluation of the load event delay check.
Key design decisions and why:
1. Microtask checkpoint in schedule_progress_check(): The old spin_until
called perform_a_microtask_checkpoint() before checking conditions.
This is critical because HTMLImageElement::update_the_image_data step
8 queues a microtask that creates the DocumentLoadEventDelayer.
Without the checkpoint, check_progress() would see zero delayers and
complete before images start delaying the load event.
2. deferred_invoke in schedule_progress_check():
I tried Core::Timer (0ms), queue_global_task, and synchronous calls.
Timers caused non-deterministic ordering with the HTML event loop's
task processing timer, leading to image layout tests failing (wrong
subtest pass/fail patterns). Synchronous calls fired too early during
image load processing before dimensions were set, causing 0-height
images in layout tests. queue_global_task had task ordering issues
with the session history traversal queue. deferred_invoke runs after
the current callback returns but within the same event loop pump,
giving the right balance.
3. Navigation load event guard (m_navigation_load_event_guard): During
cross-document navigation, finalize_a_cross_document_navigation step
2 calls set_delaying_load_events(false) before the session history
traversal activates the new document. This creates a transient state
where the parent's load event delay check sees the about:blank (which
has ready_for_post_load_tasks=true) as the active document and
completes prematurely.
Remove includes from Node.h that are only needed for forward
declarations (AccessibilityTreeNode.h, XMLSerializer.h,
JsonObjectSerializer.h). Extract StyleInvalidationReason and
FragmentSerializationMode enums into standalone lightweight
headers so downstream headers (CSSStyleSheet.h, CSSStyleProperties.h,
HTMLParser.h) can include just the enum they need instead of all of
Node.h. Replace Node.h with forward declarations in headers that only
use Node by pointer/reference.
This breaks the circular dependency between Node.h and
AccessibilityTreeNode.h, reducing AccessibilityTreeNode.h's
recompilation footprint from ~1399 to ~25 files.
Introduce the HTMLSelectedContentElement and integrate it into
<select>, <option> and HTMLParser.
See whatwg/html#10548.
There are two bugs with WPT tests which causes the third subtest
in selectedcontent.html and selectedcontent-mutations.html fail.
See whatwg/html#11882, web-platform-tests/wpt#55849.
This implements parsing part of customizable <select> spec update.
See whatwg/html PR #10548.
Two failing subtests in `html5lib_innerHTML_tests_innerHTML_1.html`
and `customizable-select/select-parsing.html` are due to the spec
still disallowing `<input>` inside `<select>`, even though Chrome
has already implemented this behavoir (see whatwg/html#11288).
Update Element::parse_fragment and Node::unsafely_set_html to
propagate exceptions.
This refactor is needed as a prerequisite for implementing the XML
fragment parser, which requires consistent error handling in fragment
parsing.
This reverts 0e3487b9ab.
Back when I made that change, I thought we could make our StyleValue
classes match the typed-om definitions directly. However, they have
different requirements. Typed-om types need to be mutable and GCed,
whereas StyleValues are immutable and ideally wouldn't require a JS VM.
While I was already making such a cataclysmic change, I've moved it into
the StyleValues directory, because it *not* being there has bothered me
for a long time. 😅
Start work on a speculative HTML Parser in Swift. This component will
walk ahead of the normal HTML parser looking for fetch() requests to
make while the normal parser is blocked. This work exposed many holes in
the Swift C++ interop component, which have been reported upstream.
There's a quirk in HTML where the parser should ignore any line feed
character immediately following a `pre` or `textarea` start tag.
This was working fine when we could peek ahead in the input stream and
see the next token, but didn't work in character-at-a-time parsing with
document.write().
This commit adds the "can ignore next line feed character" as a parser
flag that is maintained across invocations, making it work in this
parsing mode as well.
20 new passes in WPT/html/syntax/parsing/ :^)
Resulting in a massive rename across almost everywhere! Alongside the
namespace change, we now have the following names:
* JS::NonnullGCPtr -> GC::Ref
* JS::GCPtr -> GC::Ptr
* JS::HeapFunction -> GC::Function
* JS::CellImpl -> GC::Cell
* JS::Handle -> GC::Root
